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1. 11 12 15 FUEL Gals or Lbs OIL Quarts SERVICED TOTAL ADDED TOTAL FLUID IN NO 2 APU Gals BY STATION TANKS ENG wanes ay FAULTS AND OR REMARKS 18 19 16 STATUS ACTION TAKEN SIGNATURE DA FORM 2408 13 1 DEC 66 REPLACES EDITION OF 1 JAN 64 WHICH WILL BE USED AIRCRAFT INSPECTION AND MAINTENANCE RECORD For use of this form see DA PAM 738 751 the proponent army is DCSLOG Figure 1 1 DA Form 2408 13 1 7 55 1520 228 BD GENERAL INFORMATION 2 MODEL 3 SERIAL NUMBER 4 PAGE NO NO OF PAGES 3 ITEM TO BE INSPECTED REEFERENCE FREQUENCY 8 NEXT DUE D N 64 2404 18 SE JA EQUIPMENT INSPECTION LIST For use of this form see TM 38 750 the proponent agency is DCSLOG Figure 1 2 DA Form 2408 18 1 8 55 1520 228 BD GENERAL INFORMATI ON MEANINGS MARKINGS TO INDICATE DAMAGE HAS BEEN ASSESSED AND EVALUATED Draw a circle around the damage TO INDICATE NO BDAR REPAIR REQUIRED Write OK inside the circle TO INDICATE STRUCTURAL REPAIRS ARE REQUIRED Draw a second line about 1 4 to 1 2 way around the initial circle then draw slashes or crosshatch between the two circular lines STRINGER REPAIR Place an X to the left and right of the circle FRAME REPAIR Place an X above and below the circle TO INDICATE DAMAGE TO SYSTEMS REQUIRING REPAIRS Draw a series of curly cue lines about 1 4 to 1 2 way around the i
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3. rument 21 25 ar 1 0 31 51 Brace 1 25 2 50 10 Fro m ht mm Support 57 11 4 Bulkhead 30 41 22 158 Honeycomb Panel All owed Behind Pilots i NN 1 00 10 65 Lu Sum of Damage 11 MEN 190 feners on All Elements Attachment No Damage Permitted MCN K i und Ti Hid 70 1 50 10 w o mn Table 4 2 Damage Limits Forward Fuselage Condition Cont DAMAGE LIMITS COMPONENT LOCATON ELEMENT CAP FLANGE SKIN WEB NOTES MEMBER CAUTIONS Pedestal Structure 55 14 20 00 5 06R Caps Stiffeners D N x CL DENxWL O i Fes 4 Lower Shell 36 00 20 00 Honeycomb Panel 3 50 5 73 04 25 25 36 00 Inserts for Cyclic amp 12 16 amp Forward Landing Center Post 73 00 20 00 3 00L Caps 73 00 27 48 3 001 Side Webs and 225 5 87 85 72 00 3 00R Doublers i 74 52 54 50 3 00L Web Front 81 30 72 00 3 00R 80 00 62 00 3 001 Splices 87 85 72 00 3 00R 73 00 20 00 3 00L Stiffeners 87 85 7200 3 00R oso ui m Passenger Seat 96 44 29 92 24 14L Honeycomb Seat No Damage Within 114 76 31 42 24 14R Panel 4 25 5 3 of Gun Mounts If used 96 44 24 70 23 08L amp R Honeycomb Side 15 5 114 76 29 92 Panels 20 00 23 081 Honeycomb Front 40 5 96 44 29 92 23 08R Panel 96 44 20 00 23 081 Angles Side Front Gun
4. 0 16 2 DIANK u u 0 aku spa Ta 0 17 2 blank 0 hu EDEN 0 A 2 blank 0 B 1 and B 2 0 C 1 through C 4 0 Zero in this column indicates an original page Change 1 blank Technical Manual No 55 1520 228 TECHNICAL MANUAL 55 1520 228 BD HEADQUARTERS DEPARTMENT OF THE ARMY WASHINGTON D C 4 January 1991 OPERATORS AVIATION UNIT AND AVIATION INTERMEDIATE MAINTENANCE BATTLEFIELD DAMAGE ASSESSMENT AND REPAIR FOR HELICOPTER OBSERVATION OH 58A amp 58 REPORTING ERRORS AND RECOMMENDING IMPROVEMENTS You can help improve this manual If you find any mistakes or if you know of a way to improve these procedures please let us know Mail your letter or DA Form 2028 Recommended Changes to Publications and Blank Forms located in the back of this manual directly to Commander U S Army Aviation and Missile Command ATTN AMSAM MMC MA NP Redstone Arsenal AL 35898 5000 A reply will be furnished to you You may also provide DA Form 2028 information to AMCOM via e mail fax or the World Wide Web Our fax number is DSN 788 6546 or Commercial 256 842 6546 Our e mail address is 2028 redstone army mil Instructions for sending an electronic 2028 may be found at the back of this manual immediately p
5. AFTER MWO 55 1520 228 50 25 Figure 8 1 Drive Train System Sheet 4 of 4 TM 55 1520 228 BD DRIVE TRAIN SYSTEM Table 8 1 Drive Train System BDAR Assessment Procedures DRIVE TRAIN SYSTEM EVACUATE SUSTAINS DAMAGE NO CANNIBALIZE DESTROY YES VISUALLY INSPECT DAMAGE REPAIR REPLACE IS DAMAGE DEFERRABLE NO TRANSMISSION OIL OIL HOSES AND LINES COOLING AIR DUCT LEAKS OR RESTRICTIONS PER SEC II PER CHPT 9 TOP BDAR ASSESSMENT OIL PRESSURE TRANSMISSION HOUSIN TRANSMITTER LEAK BULLET DAMAGE PER SEC II PER SEC II LOW PRESSURE TAIL ROTOR GEARBO SENSING SWITCH BULLET DAMAGE PER SEC II PER SEC II 8 6 LI MI TATIONS PERSONNEL TI ME Soldier 20 Minutes REQUI RED Pliers Duct Tape item 51 Appx Wire Cutters Thin Pliable Material PROCEDURAL STEPS 0 Repairs A B C D None REQUI RED 1 Hole or tear in fabric Wrap several turns around duct to cover hole or tear Tape should extend beyond damaged area 1 to 2 inches in each direction Refer to repair A 2 Distorted duct a Using pliers and wire cutters reshape or cut away the portion of duct which would create an air flow restric tion or which is badly distorted Note If wire frame work below fabric is cut through refer to step 3 severed duct b If repair area is not at a bend portion of duct routing a repair can be applied as shown at either repair B or C If repair area is located at a bend portion of
6. FLANGE SKIN WEB CAUTIONS FS w BL EEE Bulkhead Frame Section x CL D N x WL 205 74 I LI 094 1 Clips 050 100 10 Engine Mount Back Up Structure 1000 No Damage Allowed PRENNE E 142 33 72 00 Fting Damage Allowed Table 4 4 Damage Limits Tail Boom and Landing Gear Condition DAMAGE LIMITS LOCATION MEMBER ELEMENT CAP FLANGE SKIN WEB 31 94 Intercoastals D N x CL D Nx WL 42 59 No Damage Allowed 392 Attachment Fittings No Damage Allowed Ps 31 87 Skin At any No Damage 164 10 Circumference Allowed BS164 10 Hen EE 87 42 59 pee EE 82 98 29 No Damage Allowed 116 84 150 22 174 10 Bulkheads uel et tne t 174 10 Fin Supports Jae fon fos o 174 10 Gearbox Mounting Plate 3Nvadaiv 9 8 2 0291 99 NL 6 r Table 4 4 Damage Limits Forward Fuselage Condition DAMAGELMTS LIMITS MEMBER ELEMENT FLANGE SKIN WEB CAUTIONS 182 40 No DIT T 02 No Damage Allowed ETE 87 B usc ERE 40 No Damage Allowed Honeycomb Panels 4 5 W E Limits Forward mace 1 Condition Il LOCATION LIMITS IN ELEMENT FLANGE SKIN WEB NOTES CAUTIONS eT a w Fin to Fin to Inserts Inserts No Damage Within 3 of Inserts Lem ere Fi Fwd and
7. Instrument Replacem CHAPTER 11 ELECTRICAL AND AVIONICS SYSTEM Section I Section II Introduction CHAPTER 12 FUEL SYSTEMS Section I Introduction Section Lines and Hoses Section Fuel Cell Damage CHAPTER 1 FLIGHT CONTROLS SYSTEM Section I Introduction Section Flight Control Tibes CHAPTER 14 UTILITY SYSTEMS Section I Introduction Section I I De Ice Valve or Canti CHAPTER 15 ENVIRONMENTAL CONTROL SYSTEM Section I Introduction Section Rigid Plastic Dace Section III Bleed Air Line Damage ii Electrical and Aviones mirind 1 3 5 rio n HN N N Bis Hl Rye TERSIN 55 1520 228 BD TABLE OF CONTENTS Cont Page CHAPTER 16 HOIST AND WINCHES ll s s s ooo 16 1 CHAPTER 17 p AUXILIARY POWER PLANT oen 11 1 CHAPTER 18 MISSION EQUIPMENT Section 1 Introduction 18 1 Section Gun and Mount Assembly 18 1 CHAPTER 19 EMERGENCY EQUIPMENT REFERENCES p oe W du dde Ui 408 SPECIAL OR FABRICATED TOOLS 24 aoe 9 EXPENDABLE DURABLE SUPPLIES AND MATERIALS gt SUBSTITUTE MATERI
8. 55 1520 228 BD TECHNICAL MANUAL OTTE OPERATORS AVIATION UNIT AND AVIATION INTERMEDIATE MAINTENANCE ww BATTLEFIELD DAMAGE ASSESSMENT AND REPAIR CHAPTER 1 GENERAL INFORMATION CHAPTER 2 ASSESSING BATTLEFIELD DAMAGE CHAPTER 3 GENERAL REPAIR AIRFRAME FOR CHAPTER 5 GEAR HELICOPTER CHAPTER 6 JPOWER PLANT PLANI I CHAPTER 7 07085 OBSERVATION CHAPTER 8 DRIVE TRAIN SYSTEM OH 58A OH 58C CHAPTER 9 HYDRAULIC SYSTEM CHAPTER 10 INSTRUMENT SYSTEMS CHAPTER 11 ELECTRICAL SYSTEM ITEM NSN CHAPTER 12 FUEL SYSTEM CHAPTER 13 FLIGHT CONTROLS INSIDE FRONT COVER CHAPTER 13 CHAPTER 14 UTILITY SYSTEM CHAPTER 15 ENVIRONMENTAL CONTROL SYSTEM This publication supersedes MISSION EQUIPMENT TM 55 1520 228 BD dated CHAPTER 17 EMERGENCY EQUIPMENT 17 August 1990 APPENDIX A REFERENCES SPECIAL OR FABRICATED TOOLS O ss 8 APPENDIX EXPENDABLE DURABLE SUPPLIES amp MATERIALS APPENDIX D SUBSTITUTE MATERIALS PARTS cmm APPENDIX BDAR TRAINING PROCEDURES cm AVIONICS CONFIGURATIONS HEADQUARTERS DEPARTMENT OF THE ARMY 4 January 1991 55 1520 228 80 BDAR FIXES SHALL BE USED ONLY IN COMBAT AT THE DISCRETION OF THE COMMANDER AND SHALL BE REPAIRED BY STANDARD MAINTENANCE PROCEDURES AS SOON AS PRACTICABLE AFTER THE MISSION IS COMPLETED BDAR TECHNIQUES IN THIS MANUAL PERTAIN to the following helicopters 0H 5
9. ES DSM act 4 8 Allowable Damage Limits 4 13 Air Bleed Valve 1 4 6 5 Air Duct Hose Damage eh ah da 8 6 Aluminum Tubing Damage 4204 44 9 1 Assessment Procedures Airframe poke tht ER Me Bae ee 4 2 Ali ghting DU ae teer 5 3 Drive Train 5 2 8 3 Electrical and Avionics System 44 s e s s n on 11 2 Environmental Control 5 15 3 Flight Controls We cu ee ar UN 13 2 Fuel Systems 12 2 2 2 2 e s s s s s s s s e e e ee D 9 9 3 POWER Palo ac s s y Oe Ge Ce SR T igs 3 6 2 Rotors lus drm 4E ee ORC 1 3 Utility Systems ee ote ee ee 14 2 B Battery Repair DM ee a er a sa d 11 23 ACT dr ure 1 6 Bleed Air Line 4 15 7 Blending Fuels 7 Cr D 6 Bus Bars 25 t s q s s q sq sa s s s s 11 22 Cap or Longeron Damage b eL HOP 4 18 Cap Skin Web Doubler Da mage TL TIT 4 17 Circuit Protection Device Repair 11 21
10. Figure 4 16 Typical Former Repair Sheet 2 of 2 55 1520 228 BD DO CUT STRINGER STIFFENER 7 CLEANUP ENDS Al RFRAME ME V Z77727 SN 7 N pix STIFFENER STRINGER IT 7 IF ANY GOGO LI CUT OUT INCLUDE ALL CRACKS USE 2 MAX POSSIBLE CORNER RADII 0 5 IN MIN V Figure 4 17 4 Cut a piece of substitute stringer or stiffener to extend a minimum of six fasteners beyond the damage on each end Use an angle channel or z angle extru sion if available with a cross section and strength equal to or larger than the existing stiffener stringer Sometimes a single substitute stringer or stif fener can be extended to provide support for several damages This is better than individual repairs as it wil stiffen the airframe 4 Remove rivets in the existing stiffener stringer and back drill holes in the substitute stiffener stringer to match existing holes Attempt to interpitch new fasteners within the existing rivet pattern if the area is inaccessible for back drilling rivet 5 Rivet the substitute stiffener stringer in place Figure 4 18 using the same size or larger rivets as those removed Rivet patch plate over hole using same size as existing rivets 1 54 Cutout in Damaged Skin NOTE Stiffener can be placed on out Side however this configuration is nonpreferred 7
11. Landing Gear and Support Installation Skid Tube Damage Zones Skid Repair Clamp Repair Fabricated Clamp T63 Series Engine Blocking Plate Installation Double Check Valve System Possible Alternatives Wood Plug a Sealant for Small Holes Repair Using Screw Washer and Gasket Hose Assembly Sealant Nut and Bolt Sheet Metal with Sealant and or Cherry Rivets Main Rotor System XV Ags QU Tail Rotor System Rotor Blades Damage Sensitive Areas m Rotor Blade Repair Application of Tape Repair Areas Main Rotor Blades Drive Train System Sheet 1 of 4 Zr External Components Transmission Oil System Flex Duct Repair Sheet 1 of Hydraulic System Hydraulic System Schematic Two Part Fitting Four Part Fitting Using Tube Cutter Properly Burred Tubing Damaged Tube Section Straight Tube Splice Repair Assembly Repair Fitting and Tube Installation Damaged Tube Section Complex Bends Splice Adapter Assembly Installation Installation of Socket and Sleeve Figure LIST OF ILLUSTRATIONS Cont Title Assembly of MS Fitting Union Connection Circuit Identification Crimp Splice Splicing with Terminal Lug Barrel Twist Wire Splice Replacement Section Twist Wire Splice Metal Casing Splice Splice CPP Bolted Terminal Lug Repair of Large Wires Replacement Secti
12. PER CHPT 9 AND OIL TANK PER SEC II 6 3 TM 55 1520 228 BD POWER PLANT LI MI TATIONS Revised engine start procedure WARNING Blocking of the air bleed valve will render the engine highly susceptible to surge which could result in catastrophic damage to the engine PERSONNEL REQUIRED Soldier 30 Minutes MATERIALS TOOLS REQUIRED Sheet Metal 2 X 3 In Thickness 0 032 Sheet Metal Snips PROCEDURAL STEPS Manufacture a blocking plate Loosen three bolts which secure bleed valve to compressor manifold 3 Slide blocking plate between bleed valve and mounting flange 4 Retighten three bolts which secure bleed valve to compressor manifold WARNING Blocking of air bleed valve could result in catastrophic damage to the engine The following revi sions must be incorporated 5 Complete normal engine start proce dure except for the following NOTE Bring engine up to 60 percent NI and hold for a minimum of two min utes A gradual acceleration is required to avoid a stall condition 6 4 a When increasing fuel to the engine grasp the throttle firmly with both hands and accelerate engine slowl y b Monitor TOT and N1 gauges for possible stall readings NOTE Stall usually occurs between 65 percent and 75 percent c If stall is present TOT will rise rapidly and N1 RPMs will fluctuate between 65 percent and 75 percent WARNING If ga
13. Using Figure 11 15 look under frequency column for 50 MHZ on the wave length side of the Table 6 M is shown e Use Figure 11 45 to convert meters to feet Six meters multiplied by 3 280 19 68 feet for one wave length Divide the one wave length by 8 for a 1 8 wave length antenna 19 68 2 46 feet Multiply the 1 8 wave length fa a 9 correction factor 46 ft 99 2 34 feet This is the bui of the radiating element 2 Cut the coax cable to the length of the required radiating element Remove the outer insulation and shield from the piece of coax cable and then strip a 1 inch piece of insulation from each end exposing the center conductor Figure 11 464 3 Wrap and solder the 52 Qresistor to one end of the radiating element as per Figure 11 468 This completes the fabri cation of the radiating element of the antenna 4 Next remove the structural panel on the right hand side just forward of the tail Figure 11 47 by removing twenty seven Screws 5 At the tail boom quick disconnect locate coax cable marked 1 ARC 114 1018 and disconnect it Remove the coax con nector and prepare a 4 inch pigtail ter mination on the end of the coax cable as shown in Figure 11 46C 6 Stick the radiating element of the antenna from step three with the resis tor end down into the drain hole in the M of the tail boom where it joins the fuselage Figure 11 47 INNER INSULATION REMOVE SHIELD AND
14. 13 1 for assessment procedures a Force Trim System If the force trim system is malfunctioning the aircraft is still fully mission capable with no limitations presented b Control Rods 1 Copilot to Pilot f any control rods bell cranks or linkages connecting the copilot controls to the pilot controls break or otherwise become inoperable the pilot may assume ful control for the particular function which has been damaged provided that the damaged part does not become jammed in the surrounding aircraft structure no replacement parts are available the control tube may be splice repaired refer CEEE or removed to avoid any possibility of the control tube getting jammed If the tube is removed the pilot assumes ful of the function that has been lost to the copilot 2 If any flight control systems including control rods bell cranks linkages hydraulic cylinders etc which lie between the pilot and the main rotor blade or tail rotor blade sustain damage during flight the aircraft wil E and forced to crash an 13 5 TUBES FLIGHT CONTROL GENERAL INFORMATION The following repair procedures may be used to accomplish repairs to flight contro tubes Flight control tubes connect the 13 1 VIRAL CYLINDER FORE amp AFT HYDKAU CYLINDER VALVE LATERAL 55 1520 2228 BD Figure 13 1 0 58 Flight Controls Schematic FLIGHT CONTROLS SYSTEM 13 2 m saw mom Tab
15. EXPENDED CARTRIDGE SHELL CASING Figure 11 6 Metal Casing Splice Repair 11 12 4 Insulate with tape or use plastic and string Tie in place 5 Record BDAR action taken When mission is complete as soon as practical using repair the equipment system Standard maintenance procedures OPTION 6 Bolted Terminal Lug LIMITATIONS This is a temporary type repair PERSONNEL TI ME e 1 Soldier e 10 Minutes REQUI RED MATERI ALS TOOLS REQUIRED Appropriate Size Terminal 2 ea items 54 55 56 57 58 Appx C Screw or Bolt Nut Washer Lockwasher Insulating Sleeve or Tape item 52 Appx PROCEDURAL Lugs STEPS 1 Cut ties and work broken wire to the outside of the bundle 2 Pull sufficient slack fromthe wire run toward the break so that there wil be no strain on the splice 3 Wipe wire clean with a clean dry rag or rag dampened with 1 1 1 tri chloroethane alcohol or equivalent 4 Trim broken ends of wire and install an insulating sleeve over one end of the wire and slide back and out of the way for now 5 Strip both wire ends and crimp an insulated terminal lug of the proper size to each wire end 6 Bolt terminal 11 7 lugs together as shown 55 1520 228 BD ELECTRICAL AND AVIONICS SYSTEM 1 Slide the insulating sleeve over the splice so that the ends of the insu lating sleeve extend at least 3 4 of an inch beyond the ends of each termi
16. FUNCTIONAL CHECK FOR OPERATION AND SAFETY REPAIR REPLACE 1733 B 20 UNIT NUMBER GROUND OR PHASE CIRCUIT DESIGNATION WIRE SIZE WIRE NUMBER WIRE SEGMENT Figure 11 1 Circuit Identification TM 55 1520 228 BD ELECTRICAL AND AVIONICS SYSTEM Table 11 2 Function and Designation Letters CI RCUIT CI RCUI T DESI GNATI ON DESI GNATI ON LETTER CI RCUI TS LETTER CI RCUI TS ARMAMENT F FLIGHT NSTRUMENT Bomb suspension amp release Bank and turn Guns Rate of climb Chemical Directional gyro Rocket Air position Si ght Ground position Turret Compass including flux gate Warning and other stabilized External pylons amp stores compasses Jettison fuel tanks Gyro horizon Mine dispenser Attitude gyro Driftmeter B PHOTOGRAPHI C Altimeter Gun camera Airspeed Mapping camera Accelerometer Reconnaissance camera Pitot static tube meter Camera intervalometer Warning Camera doors Camera heaters H HEATING VENTILATING AND Warning DE ICING Anti icing general C CONTROL SURFACE Battery heater Horizontal stabilizer Cabin heater Warning Cigarette lighter De icing general D INSTRUMENT other than flight Windshield defroster or engine instruments Windshield defogger Ammet er Windshield de icer Air pressure Heater blanket Free air temperature Oil immersion heater Hydraulic pressure Refrigeration Horizontal position stabilizer Ventilation Voltmeter Warning Clock Warning In order to avoid confusion with th
17. gt CRIMP WITH PROPER TOOL FOR TERMINAL SIZE TIE AT BOTH ENDS OR SHRINK IF HEAT SHRINKABLE SLEEVE USED STEP B STEP D Figure 11 3 Splicing with Terminal Lug Barrel the tape to shrink it onto the MATERI ALS TOOLS REQUIRED and soften the adhesive layer e Tape Electrical item 46 Appx located in A29 of temperature set at 900 F wiring the heat shrinkable tubing the splice onto tem the tubing to shrink it ice Use reflector 29 set at 900 F Begin in the and work toward the ends Tubi ng shrink completely onto the wire this is normal taken When as soon as repair the equipment system Standard maintenance procedures 4 Twist Wire This is a temporary type PERSONNEL TI ME 1 Soldier e 10 Minutes 11 10 e Strippers or Knife PROCEDURAL STEPS M Cut ties and work broken wire to the outside of the bundle 2 Pull sufficient slack from the wire run toward the break so that there wil be no strain on the splice 3 Wipe wire clean with a clean dry rag or a rag dampened with 1 1 1 trich loroethane alcohol or equivalent 4 Trim broken ends of the wire 5 Split all the wire ends 6 Split the strands of wire apart and twist the matching wires together as shown in 1 Cover each individual splice with electrical tact tape Insure no metal between adjacent splices con TWO THREE OR FOUR PIGTAILS TM 55 1520 228 BD ELECTRICAL AND AVIONICS S
18. p L 940511 916 jo uoljyerijddy sieday 9 10109 FIRST LAYER OF TAPE OVER SMOOTHED DAMAGE WRAP SECOND LAYER OF TAPE AROUND BLADE 3 INCH OVERLAP END OF TAPE OVERLAP WITH TOP LAYER ON OUTSIDE TOWARD TRAILING EDGE 09 622 0291 98 Wl 580108 TM 55 1520 228 BD ROTORS 8 Wrap a layer of tape around the entire blade and over the repaired area 9 Wrap exact number of tape wraps on Opposite side at approximately same span location 10 Record BDAR action taken When mission is complete as soon as practical repair the equipment system using standard maintenance procedures PATCHES PERMITTED IN SHADED AREA NOTE Figure 7 5 Repair Areas 1 8 ALL DIMENSIONS ARE IN INCHES Main Rotor Blades 55 1520 228 BD CHAPTER 8 DRIVE TRAIN SYSTEM BDAR FIXES SHALL BE USED ONLY COMBAT OR FOR TRAINING AT THE DISCRETION OF THE COMMANDER AUTHORIZED TRAINING FIXES ARE LISTED IN APPENDIX E IN EITHER CASE DAMAGES SHALL BE REPAIRED BY STANDARD PROCEDURES AS SOON AS PRACTICABLE Section INTRODUCTION 8 1 GENERAL The drive train is a 8 3 ASSESSMENT PROCEDURES Refer to system of shafts and gearboxes through Table 8 1 which the engine drives the main rotor tail rotor and such accessories as 8 4 REPAIR PROCEDURES INDEX rotor tachometer generator and hydraulic pump Sed for drive train PARA system configuration 8 2 DRIVE TRAIN DAMAGE The drive tra
19. FATIGUE FAILURE FIX FLANGE FLAKING FLUORESCENT PENETRANT FORMER FRACTURE FRAYI NG FULLY MISSION CAPABLE FMC FUNCTI ONAL GROUP FUSELAGE GLOS 4 GLOSSARY Cont A change from an original shape Wearing away of metal A combat service support function which involves the movement of recovered helicopters froma main supply route maintenance collection point or maintenance activity to higher categories of maintenance A rapid and often non standard method of repairing an item repair technique The specific cause of failure relating to categories such as cracks corrosion ballistic impact etc Sharp indentations cracks tool marks or inclusions that result in progressive yielding of one or more local areas of material Any rapid action that returns a damaged part or assembly to full or an acceptably degraded operating condition repair technique A broad ridge or pair of ridges projecting fromthe edge of a structural element providing additional strength or a place for attachment Loose particles of metal or evidence of separation of a Surface covering material A test for locating cracks and fissures in non magnetic material making use of radiation properties of fluorescent particles when exposed to ultraviolet light A curved structural element which gives the fuselage its even aerodynamic shape Normally longerons and stringers are attached and the skin is fitted tightly over all th
20. HYDRAULIC Table 9 1 Assessment Logic IS DAMAGE WITHIN ACCEPTABLE LIMIT L NO NO REPAIRS 15 SYSTEM REQUIRED NO IS REPAIR REPLACEMENT RENDER SYSTEM SAFE FEASIBLE NO FUNCTIONAL CHECK FOR REPAIR REPLACE RECOVER PROPER OPERATION AND CANNIBALIZE SAFETY DESTROY NIPPLE WS SOCKET a Figure 9 3 Two Part Fitting 9 4 TM 55 1520 228 BD HYDRAULIC SLEEVE NIPPLE SOCKET Figure 9 4 Four Part Fitting ROLLER CUTTER DRIVE SCREW DRIVE SCREW RATCHET HANDLE Figure 9 5 Using Tube Cutter 9 5 55 1520 228 BD HYDRAULIC Ratchet the cutter around the tubing applying a light pressure to the cutting wheel by intermittently twisting the setscrew Too much pressure on the cutting wheel could deform the tubing or cause excessive burring After cutting the tubing carefully remove any burrs from inside and outside of the tube If a tube cutter is not available or if tubing of hard material is to be cut use a fine toothed hacksaw preferably one having 32 teeth per inch After sawing file the end of the tube square and smooth and remove all burrs Be sure all filings and cuttings are removed from the tubing nspect the tubing end to verify its roundness its being cut square and that it is clean and free from marks and scratches Figure 9 6 illustrates properly burred tubi ng NOTE After tubing has been cut all efforts should be made to flush any residue fro
21. swell extremely 58710 B El NI TRI LE stable 011 L3 E3 F1 N398 7 BUNA 40 F to 250 F 2 B820B El F1 N256 8 BUNA N 20 F to 225 F 2 SB815BE1 Fl 1532 98 BUNA N 20 F to 250 F 2 ess steel 0115 ulic fluids ine pneumatics al 0 Q hy fluids pneu High extru 2 resistance lt gt Li T T T 3 3 T T resistance Otary Seals t use with v 8915B N183 9 BUNA N 30 F to 250 F B915B E3 N552 9 BUNA N 30 F to 250 F NEN TA 605B El E3 ur 2 3 2 3 Tos 2 3 E3 F2 5 SI LI CONE 80 F to 450 F 10 None 11 545 El ast omer 20 F to 400 F gn tempera oils aromatic Fluoro 1 solvents chemical None V311 9 Elastomer 20 F to 400 F service 5727 9 171 9 18 Blank TM 55 1520 228 BD 1g peral oils aromatic solvents chemical Service AMS7278 5418 6 SILICONE 80 F to 450 F 6 TATO5B El E3 LF 5411 1 SI LI CONE 80 F to 450 F 604 7 80 HYDRUALIC TM 55 1520 228 BD CHAPTER 10 NSTRUMENTS BDAR FIXES SHALL BE USED ONLY COMBAT OR FOR TRAINING AT THE DISCRETION OF THE COMMANDER AUTHORIZED TRAINING FIXES ARE LISTED IN APPENDIX E IN EITHER CASE DAMAGES SHALL BE REPAIRED BY STANDARD PROCEDURES AS SOON AS PRACTICABLE There are no BDAR repairs offered for the instrument systems 10 1 10 2 Blank 55 1
22. th tape or AR action taken on as practical repair the equipment system using standard maintenance SLEEVE WASHER STRING TIE OR TIE WRAP IM LOCKWASHER Figure 11 7 Bolted Terminal Lug Repair of Large Wires WASHER WASHER SLEEVE SCREW OR BOLT SLEEVE PIPN EE LOCKWASHER NUT LOCKWASHER 3 4 3 4 3 4 NEW WIRE SECTION Figure 11 8 Replacement Section Terminal Lug Repair WIRE RAMMED TOGETHER re ends together so p control cable clamp le means Figure 11 9 sulation sleeve When mission is SCREW CLAMP OR EQUAL Figure 11 9 Ram Wire Repair Method 11 6 WIRES WIRE REPAIR SEGMENTS UNSHIELDED GENERAL INFORMATION The BDAR electri cal wiring kit has wire replacement segments for replacement sections up to 9 inches in length The replacement sections are located in the wire repair kit Refer to Table 11 4 CAUTION Make sure aircraft power is off Disconnect battery before touching any wires LIMITATIONS Dependent on splice method used to connect replacement segment PERSONNEL TIME REQUIRED 1 Soldier 20 Minutes MATERI ALS TOOLS REQUIRED Replacement Segment Refer to Table Table 11 4 e Splice item 10 Appx e Insulation Sleeve Tape item 49 e Crimp Tool item 10 Appx 8 PROCEDURAL STEPS 1 Cut out damaged wire up to 9 inches in length 2 Strip wires refer tol Table 11 4 3 Splice repl
23. 1 Soldier 10 Minutes Per Wire MATERI 15 TOOLS REQUIRED Replacement Pins Sockets item 2 Appx BJ e nsertion Extraction Tool item 2 Appx 8 e Knife PROCEDURAL STEPS 1 Solder or crimp wires to pin sockets Figure 11 33 2 Insert the pins sockets into the connector TM 55 1520 228 BD ELECTRICAL AND AVIONICS SYSTEM 3 Record BDAR action taken When complete as soon as mission is practical repair the equi pment system using standard maintenance procedures CONNECTOR PIN CONNECTOR SOCKET Figure 11 33 Connector Pin and Socket Supergl ue or secure t ment pin getting surface OPTION 2 NOTE he original or epoxy may be used to replace back into place Avoid glue or epoxy on contact of pin Bridge Across Fully Damaged Connector Partially or LIMITATIONS Temporary repair PERSONNEL TI ME REQUIRED 1 Soldier e 10 Minutes Per Wire MATERI ALS TOOLS REQUIRED ice item 10 Appx e Wire items 61 62 Appx e Wire Spl PROCEDURAL STEPS 1 Locate the damaged wire ends that go into connector 2 Splice together connector the appropriate wires The splice wil bypass the 11 33 55 1520 228 80 ELECTRICAL AND AVIONICS SYSTEM 3 Record BDAR action taken When mission is complete as soon as practical repair the equipment system using standard maintenance procedures OPTION 3 Cannibalizing Connector
24. 619 9167 Sandpaper 80 Grit PP101 81368 SH 4 6850 00 264 9038 Solvent Cleaning P D 680 81348 BBL 48 5940 00 500 8723 Splice Conductor Crimp Style EA Wire Size 10 MS25181 3 96906 19 3970 00 419 8723 Tape Electrical Black Insulation RO 50 1510 00 074 5124 Tape Green 58536 A A 1586 RO 5 5970 00 812 7387 Tape Teflon 82577 RO 5 1510 00 266 6712 Tape A A 883 58536 RO 53 1510 00 154 2522 Tape A A 113 58536 RO 5 3 TM 55 1520 228 BD APPENDIX C APPENDIX C Section EXPENDABLE SUPPLIES AND MATERIALS LIST Cont ITEM UNIT OF NUMBER NSN DESCRI PTI ON ISSUE 54 5940 00 283 5380 Terminal Lug Crimp Style Stud BX Size 6 Wire Gage 16 14 59 5940 00 143 4780 Terminal Lug Crimp Style Stud BX Size 10 Wire Gage 16 14 56 5940 00 143 4777 Terminal Lug 81349 MIL T 7928 BX 54 5940 00 804 9184 Terminal Quick Disconnect BX Wire Gage 16 14 MS27429 2 96906 58 5940 00 804 9185 Terminal Quick Disconnect BX Size 18 MS27429 1 96906 59 6810 00 664 0387 i 1 1 1 T 620 CN 48 60 6515 00 324 5500 LLL 5 007 20 BX 61 01409 00 252 0499 Wire Insulated Size 14 RL BB74 50072 46522 62 6145 00 435 8613 Wire Insulated Size 18 RL M81044 12 18 9 81349 NOTE For expedient repair of flex hoses and metal tubes refer to tables listed in Chapter 9 AMC BDR kits contain all necessary tools materials and test equipment for electrical repairs C 4 TM 55 1520 228 BD APPENDIX D SUBSTI
25. CANNIBALIZE DESTROY DAMAGE REPAIRABLE REPAIR REPLACE KID TUBE PER SE 11 AFT FORWARD CROSSTUBE PER 55 1520 228 2 FORWARD SKID SADDLE PER 55 1520 228 23 AFT FORWARD CROSSTUBE PER TM 55 1520 228 23 SKID SHOES PER SEC II 9 3 55 1520 228 BD ALI GHTI NG GEAR c Visually inspect structures sup porting alighting gear attachment points and transmission attachment points for any signs of structural distress such as buckling cracks rupture deformation popped rivets or elongated rivet holes If no such damage is found replacement of alighting gear may be deferred if it is Still functional and aircraft may be released for fully mission capable flight Watch for any unusual vibra tions in flight Inspect after every flight until alighting gear can be repl aced Section IIl 5 71 SKID DAMAGE GENERAL INFORMATION Landing skids may be damaged by wear or enemy fire If time is available repair can be per formed to prevent further damage to landing skids LI MI TATIONS PERSONNEL ME e2 Soldiers 2 Hours MATERI ALS TOOLS REQUIRED 0 032 In Sheet Metal Blind Fasteners item 36 Appx Drill Bit and Motor PROCEDURAL STEPS Use care in landing REQUI RED L Form plate to fit snug around ski d Drill oversize holes along each edge 0 match attachment holes in skid tube d If alighting gear supporting structure is damaged but still func tional an
26. Figure 4 27 Patch Plates One Side Accessible Repair TM 55 1520 228 BD AI RFRAME MAKE PATCH FROM 3 16 BLIND RIVETS 2024 T3 OR 7075 T6 2 DIA EDGE DISTANCE ALCLAD ALUMINUM 4 DIA RIVET SPACING THRU ONE SKIN ONLY REPAIR PATCH AND FASTENERS RIVETS TOP AND nd SEALANT HM 12 MAX SECTION A A Figure 4 28 Repair of Re Core Panel Damage Over 8 Inches Both Skins and Core 55 1520 228 BD RF RAME PROCEDURAL STEPS 1 Remove protruding sections of damaged skins and core Clean area with solvent 2 Cut patch plate to fit over hole allowing 1 inch overlap on all sides 3 Lay out and drill rivet pattern on Overlapping area 4 Apply sealant to underside of patch plate on overlapping area 5 Assemble patch plate to panel with rivets 6 Record BDAR action taken When mission is complete as soon as practical repair the equipment system using standard maintenance procedures 4 21 WINDOW SHIELD WINDOW DAMAGE GENERAL INFORMATION n general repairs to transparencies are at best make shift and usually result in serious impairment of clear vision charac teristics Damaged sections should be replaced 5 soon as possible LIMITATIONS Restricted vision Inspect after every flight for damage growth PERSONNEL TI ME el Soldier el Hour REQUI RED REQUI RED Safety Wire item 23 Appx Sealant item 4 Tape item PROCEDURAL STEPS 1 S
27. Fuel Shut Off Cable Fuel Shut Off Lever Auxiliary Fuel Cell Fitting PROPER OPERATION AND TM 55 1520 228 BD FUEL SYSTEMS Table 12 1 Fuel System Assessment Procedures FUEL SYSTEM DAMAGE AMAGE WITHIN PTABLE LIMITS IS D ACCE NO REPAIR 15 REPAIR REPLACEMENT FEASIBLE NO ONAL CHECK FOR REPAIR REPLACE RECOVER CANNIBALIZE DESTROY HOSES AND LINE PER CHPT 9 O RING DAMAGE PER CHPT 9 FUEL SUBSTITUTE PER SEC 11 FUEL CELL DAMAGE PER SEC II 55 1520 228 BD FUEL SYSTEMS Section Ill 12 7 FUEL CELL DAMAGE GENERAL INFORMATION The fuel cells restrict the catastrophic loss i fuel in survivable crashes cified in this section however wil not necessarily return the cells to their original crash resistant level Fuel cell damage can be categorized as follows a Nonrepairable 1 Damage to metal plate of fit tings on tank which causes leakage 2 Damage to tank wall which exceeds 3 inches 3 Damage within 2 inches of metal fitting b One Time or Emergency Flight Capability Repair Mechanical Clamp Repair option 1 c 100 Flight Hour Capability Repair 1 Adhesive repair option 2 2 Flat panel repair one plane option 3 3 Two plane repair option 4 4 Three plane repair option 5 OPTION 1 Mechanical Clamp Repair LI MI TATIONS PERSONNEL TIME REQUIRED Soldier 30 minutes Em
28. Install jumper from terminal Al to terminal A2 Reference 11 45 Type A and B Install hardware on terminals Al and A2 Tighten hardware to hold jumper in pl ace 8 Remove jumper as soon as emergency evacuation flight is completed TM 55 1520 228 BD ELECTRICAL AND AVIONICS SYSTEM DRAWING PART DESI GNATI ON NUMBER FUNCTI ON K6 52418301 Relay BATTERY MS24183D1 Relay External Pur 11 3 2791G200F 9 Relay Gen Fail K12 52418301 Relay Line Cont K3 MS24183D1 Relay Non Ess Bus BB 4761A Battery Figure 11 42 Location of Power Relays 11 43 TM 55 1520 228 BD ELECTRICAL AND AVIONICS SYSTEM A1 O in 8 8 E TYPE A Figure 11 43 11 0 w O12 130 449 4 O 14 3 X2 Al O 2 Gece Q TYPE B Block Diagram Typical Power Relays Figure 11 44 9 Record BDAR action taken When mission is complete as soon as practical repair the equipment system using standard maintenance procedures 11 25 SUBSTITUTE EMERGENCY ANTENNA FIELD EXPEDIENT This section contains expedient repair procedures to restore radio communication needed to complete the mission GENERAL INFORMATION These procedures give instructions for use of substitute and or construction of replacement anten nas that can be used to transmit and receive radio messages 11 44 Jumper Wire Fabrication WARNT NG Do not touc
29. OR DESTROYED GO TO CHPT 7 ARE THE TAIL AND MAIN ROTOR BLADE ASSEMBLIES DAMAGED LYES IS REPAIR DEFERRABLE OR FEASIBLE GIVEN THE MATERIALS TIME AND METHODS AVAILABLE YES DETERMINE WHETHER THE AIRCRAFT SHOULD BE RECOVERED CANNI BALIZED OR DESTROYED OPEN THE ENGINE TRANSMISSION DRIVE TRAIN AND HYDRAULIC COMPARTMENTS FOR INSPECTION INSPECT FOR CRACKS LEAKS BREAKS ETC ALSO CHECK AROUND THE FUEL CELL PANELS CONTINUE NEXT PAGE 55 1520 228 BD ASSESSING BATTLEFIELD DAMAGE Table 2 2 General Assessment Cont IS THE EXTERIOR OF THE ENGINE SYSTEM O K NO GO TO CHPT 6 15 THE EXTERIOR OF THE TRANSMISSION DRIVE TRAIN O K NO IS REPAIR DEFERRABLE OR FEASIBLE GIVEN THE MATERIALS TIME AND METHODS AVAILABLE YES NO DETERMINE WHETHER THE AIRCRAFT SHOULD GO TO BE RECOVERED CANNI CHPT 8 BALIZED OR DESTROYED IS REPAIR DEFERRABLE OR FEASIBLE GIVEN THE MATERIALS TIME AND METHODS AVAILABLE IS THE EXTERIOR OF THE HYORAULIC SYSTEM 0 DETERMINE WHETHER THE AIRCRAFT SHOULD BE RECOVERED CANNI BALIZED OR DESTROYED GO TO i CHPT 9 IS REPAIR DEFERRABLE OR FEASIBLE GIVEN THE MATERIALS TIME AND METHODS AVAILABLE DETERMINE WHETHER THE AIRCRAFT SHOULD BE RECOVERED CANNI BALIZED OR DESTROYED E NEXT 2 5 55 1520 228 BD ASS
30. OVER BUNDLE CLOVE HITCH AND SQUARE KNOT Figure 11 25 Tie Tape Repair Procedure 4 Record BDAR action taken When mission is complete as soon as practical repair the equipment system using standard maintenance procedures NOTE Harness branches can be secured by tying OPTION 3 String or Wire Repair LIMITATIONS This is a temporary repair PERSONNEL TIME REQUIRED e 1 Soldier e 1 Minute MATERI ALS TOOLS REQUIRED e Wire or String PROCEDURAL STEPS 1l Tie wires or groups using type knot Shown in Figure 11 25 TM 55 1520 228 BD ELECTRICAL AND AVIONICS SYSTEM CAUTI ON Do not tighten wire or string too much as wire or string can cut into or deform insulation 2 Space ties at 12 inches or less 3 Record BDAR action taken When mission is complete as soon as practical repair the equi pment system using standard maintenance procedures 11 15 COAX SPLICE FOR RG 136 U AND RG 179B U GENERAL INFORMATION There are various coax splices in the wiring repair kit that may be used for the different types and sizes of coax cable LIMITATIONS This is a temporary repair PERSONNEL TIME REQUIRED 1 Soldier e 15 Minutes MATERI ALS TOOLS REQUIRED e Coax Splice item 10 Appx e Stripper or Knife Crimp Tool AD 1377 item 10 e Reflector item 10 Appx e Heat Gun Heat Source item 10 Appx PROCEDURAL STEPS 1 Prepare coax cable Figure 11 26 Refer t
31. Phillips nl e a A 50 Shell Oil 640 Aeroshell 650 Sinclair Superjet A Superjet A 1 Standard Oil Co 4 Jet Kerosene Jet A 1 Kerosene Chevron Chevron A 50 Chevron A 1 Texaco Avjet A Avjet 4 1 Union Oil Union P 4 76 Turbine Fuel D 9 TM 55 1520 228 BD APPENDIX D Table D 7 Alternate and Expedient Fuel Blends BASE FUEL EXTENDER 50 MAXI MUM NOTE Fuel may be extended on an alternate basis with the following blends up to a half and half mixture Any Primery Fuel Any Alternate Fuel Any Primary Fuel Any Alternate Fuel MIL F 815 Distillate NATO F 76 Navy Distillate Any Primary or Alternate Fuel Any Primary or Alternate Fuel Any Alternate or Primary Fuel Dry Cleaning Solution P D 680 Type and 11 Dry Cleaning Solution AMSTM D 484 11 LEL IV Petroleum Spirits ASTM D 235 1 11 IIL IV CAUTI ON The helicopter shall not be flown when emergency fuel has been used for a total cumulative time of 50 hours TM 55 1520 228 BD APPENDIX D Section 111 LUBRICANTS AND HYDRAULIC FLUIDS 0 6 SCOPE This section lists pri 2 They may allow an increase in mary alternate and expedient lubri wear because of improper viscosity cants and hydraulic fluids 3 They may cause seals to swel 0 7 GENERAL or create deposits because of improper composition a The lubricants and hydraulic fluids used in 0H 58 systems and com 0 9 LUBRICANTS AND HYDRAULIC FLUIDS ponents
32. T 15 Submitter LName Smith 16 Submitter Phone 123 123 1234 17 Problem 1 18 Page 2 19 Paragraph 3 20 Line 4 21 NSN 5 22 Heference 6 23 Figure 7 24 Table 8 25 ltem 9 26 Total 123 27 Text This is the text for the problem below line 27 00 10 Use Part Il reverse for Repair Parts Spe DATE RECOMMENDED CHANGES TO PUBLICATIONS AND cial Tool Lists RPSTL and Supply Catalogs BLANK FORMS Supply Manuals SC SM For use of this form see AR 25 30 the proponent agency is ODISC4 8 3 0 02 TO Forward to proponent of publication or form Include ZIP Code FROM Activity and location Include ZIP Code Commander U S Army Aviation and Missile Command MSG Jane Q Doe ATTN AMSAM MMC MA NP 1234 Any Street Redstone Arsenal AL 35898 Nowhere Town AL 34565 PART 1 ALL PUBLICATIONS EXCEPT RPSTL AND SC SM AND BLANK FORMS PUBLICATION FORM NUMBER DATE TITLE Organizational Direct Support And General Support Maintenance Manual for Machine Gun 50 TM 9 1005 433 24 16 Sep 2002 caliber and M3P Machine Gun Electrical Test Set Used On Avenger Air Defense Weapon System ITEM PAGE PARA LINE FIGURE TABLE RECOMMENDED CHANGES AND REASON NO NO GRAPH NO NO NO 0005 Test or Corrective Action column should identify a different WP number PG3 Reference to line numbers within the paragraph or subparagraph TYPED NAME GRADE OR TITLE TELEPHONE EXCHANG
33. TM 55 1520 228 BD HYDRAULIC Table 9 2 Seals Reference and Temperature Guides Chart Cont DESI GNATI ON PARKER BASE TEMP GUI DE DURO SERVICE AND sees asrmor3s sar_ conrouno com sem ere specitications _ Mineral oil amp hy draulic fluid water 58620 B El NI TRILE Steam coolants E3 F1 N525 6 BUNA N 40 F to 250 F pneumatic service 59020 NITRILE 2 3 SB712BE1 F2 N506 7 BUNA N 65 F to 225 F SB715BEl F2 N103 7 BUNA N 65 F to 225 F fuel amp low tempera ture resistance AMS7271 clal gasoline mineral oils amp hydraulic fluids pneumatic service ie SB715B E1 E3 F2 119 1 40 F to 250 F Mur uid SB720B El F2 N180 7 20 F to 250 F SB715E1 Fl N214 7 40 F to 250 F NITRILE matics SAE 120R 2 3 SB715BE1 F1 N219 7 BUNA N 40 F to 250 F 70 Class 1 UL Listed Petroleum base lubricating oil resistant 57274 Listed by Underwriter Laboratories for fuels oils and gasolines Mineral oils amp hydraulic fluids gasolines pneu n oil amp ic fluids ies gasolines i 0115 5B715BE1 Fl 109 30 F to 250 F 70 ics TM 55 1520 228 BD HYDRAULIC Table 9 2 Seals Reference and Temperature Guides Chart Cont sus conpouno CONT SERV METE ASTMI D735 58T COMPOUND POLYMER CONT SERV METER SPECI FI CATI ONS Water OW Service
34. TM 55 2840 228 BD Technical Manual Operators Aviation and Intermediate 4 Jan 1991 Maintenance Battlefield Damage Assessment and Repair for Helicopter Observation OH 58A amp OH 58C ITEM PAGE PARA LINE FIGURE TABLE RECOMMENDED CHANGES AND REASON GRAPH NO Reference to line numbers within the paragraph or subparagraph TYPED NAME GRADE OR TITLE TELEPHONE EXCHANGE SIGNATURE AUTOVON PLUS EXTEN SION DA FORM 2028 FEB 74 REPLACES DA FORM 2028 1 DEC 68 WHICH WILL BE USED USAPA V3 01 TO Forward direct to addressee listed in publication FROM Activity and location Include ZIP Code Commander U S Army Aviation and Missile Command ATTN AMSAM MMC MA NP Redstone Arsenal AL 35898 PART Il REPAIR PARTS AND SPECIAL TOOL LISTS AND SUPPLY CATALOGS SUPPLY MANUALS PUBLICATION NUMBER DATE TITLE Technical Manual Operators Aviation and Inter z N mediate Maintenance Battlefield Damage Assessment TM 55 2840 228 BD 4 Jan 1991 and Repair for Helicopter Obsevation OH 58A amp OH 58C TOTAL NO PAGE COLM LINE NATIONAL STOCK REFERENCE FIGURE ITEM OF MAJOR RECOMMENDED ACTION NO NO NO NUMBER ITEMS SUPPORTED PART Ill REMARKS Any general remarks or recommendations or suggestions for improvement of publications and blank forms Additional blank sheets may be used if more space is needed TYPED NAME GRADE OR TITLE TELEPHONE EXCHANGE AUTOVON SIGNATURE PLUS EXTENSION USAPA V3 01 The Metric S
35. WINDSHIELD FS21 25 WL51 95 WL44 15 INSTRUMENT PANEL SKIN CONSOLE LOWER WINDOW 20 0 5 36 22 FS55 1 FS21 24 WL32 50 FS32 75 557 10 130 10 WL29 31 WL20 00 FS36 22 23 39 16 0 CONSOLE Figure 4 11 Fuselage Pylon Support Structure Sheet 1 of 5 55 1520 228 BD WL31 42 FS96 44 FS114 76 BL24 14 PASSENGER SEAT BL24 14 k WL29 92 WL21 00 FS57 11 FS74 54 BL21 10 PILOTS AND COPILOTS SEAT BL19 45 B Figure 4 11 Fuselage Pylon Support Structure Sheet 2 of 5 Al RFRAME TM 55 1520 228 BD RF RAME 573 04 FUSELAGE STATION 73 BULKHEAD a WL71 96 S vu e WL67 92 ce SQ Sf DC Ceres WL54 89 87 2 lt Gas Cc 3 a A gt 587 85 10 65 WL30 29 p BL17 31 Bea WL69 00 BL3 00R BL3 00L WL54 50 CENTER POST WL27 48 sss od 7 3 06 Figure 4 11 Fuselage Pylon Support Structure Sheet 3 of 5 55 1520 228 BD Al RFRAME FUSELAGE STA 130 BULKHEAD WL72 00 WL51 72 5111 11 29 47 W 21 00 WL72 00 WL50 04 PASSENGER SEAT BACK BULKHEAD Figure 4 11 Fuselage Pylon Support Structure Sheet 4 of 5 TM 55 1520 228 BD Al RFRAME 5123 62 REAR SUPPORT STRAP FORWARD SUPPORT STRAP FORWARD PYLON ROOF BEAM Figure 4 11 Fuselage Pylon Support Structure Shee
36. YES NO REPAIRS 15 REPAIR REPLACEMENT FEASIBLE NO FUNCTION CHECK FOR PROPER OPERATION AND SAFETY RECOVER CANNIBALIZE DESTROY REPAIR REPLACE SKIN STIFFENER PER SEC II CAP SKIN WEB DOUBLER PER SEC II LONGERON PER SEC IT FRAME BULKHEAD SKIN AND sQ d h mr A II STRINGER PER SEC HONEYCOMB CORE FLOOR OR PANEL PER SEC II WINDSHIELD WINDOW PER SEC II TAIL BOOM PER SEC II 4 2 TM 55 1520 228 BD AIRFRAME MAIN ROTOR BLADES AND HUBS ENGINE TRANSMISSION ACCESSORIES AND COWLING TAIL BOOM FIN AND STABILIZER FORWARD FUSELAGE AFT FUSELAGE Figure 4 1 Aircraft Sections 4 3 TM 55 1520 228 BD ATRFRAME a the damage appears to be deferrable b a detail assessment can be made and the damage can be repaired by BDAR techniques within the time available to return the aircraft to service in the ongoing battle adequate assessment be made and the damage can be repaired by BDAR techniques to enable the aircraft to self recover d a detail assessment cannot be made and or the damage cannot be re paired by BDAR techniques within the available time The aircraft shall be scheduled for standard repair e The aircraft is damaged beyond repair and he shall arrange for its disposition i e recovery can
37. caused by this action 1 4 DEFINITIONS a Battlefield Damage Any incident such as combat damage random failures operator errors accidents and wear out failures which occur on the battlefield and which prevent the helicopter from accomplishing its mission b Repair or Fix Any expedient action that returns a damaged part or assembly to a full or an acceptably degraded operating condition including 1 Short cuts in parts removal or installation 2 Installation of components from other equipment that can be modified to fit or interchange with components on the damaged equipment 3 Repair using parts that serve a noncritical function elsewhere on the same equipment for the purpose of restoring a critical function 4 Bypassing of noncritical com ponents in order to restore basic func tional capability 5 Expeditious cannibalization procedures 1 2 are required to make the repair who can do the repair e g crew maintenance team or maintenance support team and where the repair should be made The assessment procedure includes the following steps 1 Determine if the repair can be deferred or if it must be done 2 Isolate the damaged areas and components 3 Determine which components must be fixed 4 Prescribe fixes 5 Determine if parts or com ponents materials and tools are available 6 Estimate the manpower and Skill required 7 Estimate t
38. dient procedure will allow former repair from stray stock 4 16 SKIN STIFFENER DAMAGE GENERAL INFORMATION These repairs are applicable to any skin stiffener stringer structure such as the fuselage fairings and many secondary structures other than sandwich construction OPTION 1 Patch Plate and Substitute Stiffener Stringer LIMITATIONS None Condition 1 Inspect after every flight for damage growth PERSONNEL REQUIRED Soldiers e Hours MATERI ALS TOOLS REQUIRED Substitute Stiffener or Stringer Section e Skin Patch Cherry Rivets item 37 Appx C PROCEDURAL STEPS 1 Remove sections of the aircraft skin and stiffener stringer containing the damage Smooth and round the cutout Cleanup ends of the stiffener stringer Stop drill any remaining a 2 Cut and fit a skin patch one gauge thicker allowing overlap for at least two rows of rivets Figure 4 18 55 1520 228 BD Al RFRAME USE BOLTS BLIND BOLTS OR RIVETS ANGLE OR T PROFILE AL ALLOY 2024 UNLESS STEEL REQ D MINIMUM DRESSING OUT FRAME REPAIR MATERIAL DESCRIPTION MATERIAL ANGLE OR DOUBLER AL ALLOY T PROFILE AL ALLOY 2024 OR STEEL SHEET USE FRENCH CURVES OR 7075 STEEL LOCKTITE TO LOCK NUTS SECTIONS SHEET AS REQ D DOUBLER Figure 4 16 Typical Former Repair Sheet 1 of 2 TM 55 1520 228 BD Al RFRAME 3 16 IN STOP DRILL SECTIO B B section
39. low voltage Potentials as low as 50 volts may cause death under adverse conditions For Artificial Respiration refer to FM 21 11 55 1520 228 BD EXTERNAL STORES Prior to any helicopter maintenance functions that require external stores be removed JETTISON cartridge shall be removed To prevent injury to personnel and damage to equipment remove jettison cartridges from stores ejection device prior to placing helicopter in a hangar All ground safety pins must be removed before flight Failure to do so will prevent emergency jettison of stores FIRE EXTINGUISHER Exposure to high concentrations of monobromotrifluoromethane CF3BR extinguishing agent or decomposition products should be avoided The liquid should not be allowed to come into contact with the skin as it may cause frost bite or low temperature burns FUELING AND FUEL REPAIRS When refueling helicopter the refueling vehicle must be parked a minimum of 20 feet from the helicopter Before starting the fueling operation always insert fueling nozzle grounding cable of fuel truck into GROUND HERE receptacle Refer to FM 10 68 When defueling turn off all electrical switches and disconnect external power from the helicopter The helicopter must be electrically grounded prior to defueling Fuel line and tank repairs often involve handling of highly flammable material Mishandling can result in serious injury or death GROUNDING HELICOPTER The helicopter should be e
40. of an item of materiel from one piece of equipment for immediate use in another Generally the rules for cannibaliza tion controlled exchange provided in TM 55 1500 328 25 as modified by local authority will prevail ngine torque and other characteristics In BDAR repairs the limitations recom mended should be followed Emergency flight procedure 55 1520 228 10 should further be consulted k Maintenance Collection Point point operated by AVIM unit for the collection of equipment for repair Maintenance Support Team MST A team of AVIM mechanics and technical specialists who are trained in assessing battlefield damage and field repair procedures m Maintenance Team MT Helicopter crew chief or AVUM mechanics technicians h Evacuation A combat service sup port function which involves the mov ment of recovered helicopters from a main supply route maintenance collec tion point or maintenance activity to higher categories of maintenance The materiel may be returned to the user to the supply system for reissue or to property disposal activities i Recovery The retrieval of immo bile inoperative or abandoned OH 58 helicopter from the battlefield or immediate vicinity and its movement to a maintenance collection point the main supply route or a maintenance activity for disposition repair or evacuation Section II 1 6 BDAR CHARACTERISTICS bility r
41. 10 Appx Heat Gun item 10 Appx PROCEDURAL STEPS 1 Prepare coax cable Figure 11 26 Refer 11 5 2 Slide the shield sleeve and filler Sleeve onto one of the coax cables in the order given 3 Insert center conductors to overlap in center conductor splice Barrier Sleeves of center conductor splice fit under cable braids Fi qure 11 30 Heat using reflector temperature set at 900 F 4 Shrink the filler sleeve over the splice Use same reflector and tem perature Keep hot air away from shield sleeve 5 Center and shrink the shield sleeve over the splice area so that the solder melts and flows Shield sleeve braid must overlap coax braid at both ends Refer to lFigure 11 31 Use same reflector and temperature 6 Record BDAR action taken When mission is complete as soon as practical repair the equi pment system using standard maintenance procedures CABLE BRAID OVER BARRIER SLEEVES CENTER CONDUCTOR SPLICE Figure 11 30 Coax Splice with Cable Braid over Barrier Sleeves 11 32 OVERLAP OVERLAP SHIELD SLEEVE Figure 11 31 Coax Repair with Cable Braid over Barrier Sleeve 11 19 COMPONENT BRI DGI NG GENERAL INFORMATION In most cases it will be quicker not to replace bulkhead connectors junction boxes or terminal strips These circuits can be repaired by bridging the damaged area with jumper wires spliced in to eliminate the damaged area or component Fig
42. 8 Radar Altimeter System AN APN 209 Sheet 1 of 2 F 16 55 1520 228 BD APPENDIX F DRAW NG PART DESI GNATI ON NUMBER FUNCTI ON 1 M39002 01 0072 Resistor Fixed 2 527413 108355 Connector Plug Electric 3 KA 59 96 Connector Plug 4 KA 59 96 Connector Plug 5 RT 1115 APN 209 IND RCVR Transmitter 6 KA 59 96 Connector Plug 1 AS 2595 APN 194 Antenna 8 KA 59 96 Connector Plug 9 AS 2595 APN 194 Antenna 10 M591528 0N18 Knob Control Figure F 8 Radar Altimeter System AN APN 209 Sheet 2 of 2 Table F 8 Wiring Table Radar Altimeter ANDRE E 0H 58C UMBER ND p ND APN209 21A 210905174 3408E1P 1 APN209 22A 2408DS1P3 3408E2P1 TM 55 1520 228 BD APPENDIX F DRAWI NG DESI GNATI ON 1 2 3 com c Figure 9 PART NUMBER T5 1843 RT 859 APX 72 C 6280A P RT 1285 APX 100 VJ 206 077 109 1 KI T LA TSEC MT 3513 AT 884 APX MT 3809 APX 72 FUNCTI ON Test Set Transponder Recei ver Transponder Control Transponder APX Transponder The APX 100 V Used On The 0H 58C Does Not Require The 5 1843 Antenna Used Only On 58 With APX 100 Comput er Mount Antenna Mount Transponder IFF System AN APX 72 100 TM 55 1520 228 BD APPENDIX F SX106A18 SPLICE X706B18 82 5 707 2 P232 SX712A22 SX714A22 50143422 SX755A22 SX736A22 SX757A22 915842 5162422 51763422
43. 9 AN ARC 114 AN ARC 114 C 8157 ARC A5 2405 A5 2610 ARC TSECI KY 28 TSECI KY 58 A5 2486 ARC LPF 40 028 206 022 114 1 206 022 114 3 KC 59 212 KC 19 120 Figure F 4 FUNCTION Filter Low Pass Board Capacitor Radio Set No 1 FM Radio Set No 2 FM Control Indicator TSEC KY 28 Antenna No 2 FM Antenna R H No 1 FM Com Security Set Com Security Set Antenna L H No 1 FM Filter Low Pass Antenna No 1 FM USBL on 68 16687 thru 72 21454 USBL on 72 21455 and Subq Connector Plug Connector Electrical VHF FM Communication System TM 55 1520 228 BD APPENDIX F Table F 4 Wiring Table VHF FM Communication System gt LARC114 2422 9A22 10422 11422 17422 18422 19422 26A22 27A22 lt ArT oco mm SOD HI I ODD c OO WO OO WO OO WO c LARC114 2422 9422 10422 11422 17422 18422 19422 20422 27A22 28A22 1014 1018 m 103A 2ARC114 11B22 BLK 20822 RED 101A 1018 1 Underlined Pin Numbers Denote Lower Case 2 Denotes PR S Pair Twisted with Shield TM 55 1520 228 BD APPENDIX F Gyromagnetic Compass Set AN ASN 43 and Connecting Cables Sheet 1 of 2 Figure F 5 F 10 TM 55 1520 228 BD APPENDIX F DRAWI NG PART DES
44. Aft Cross No Damage Allowed Tubes Forward Console 1 00 20 00 5 06R Caps Stiffeners 110 220 5 32 75 44 50 3 06L Doublers i 32 75 44 50 3 06L 32 75 21 00 5 06R Caps Stiffeners 32 75 23 39 5 06R Skins Webs 4 50 5 44 00 32 50 3 06L i 32 75 21 00 5 06R Skin 1 00 5 44 00 23 39 3 06L i Honeycomb 44 00 21 00 5 06R 8 00 5 Panel 57 10 32 50 3 06L dNvadaiv 9 8 2 0291 99 0 Table 4 5 Damage Limits Forward Fuselage Condition Cont LOCATION DAMAGE LIMITS MEMBER ELEMENT FLANGE SKIN WEB CAUTIONS Panel 57 10 32 50 3 061 Instrument Panel 21 25 44 15 5 02R Shroud 37 56 51 95 3 02L 1 50 Front Seat 21 00 Honeycomb Does Not Include Support 30 41 Bulkhead 1 05 5 Manufacturer s 57 11 Holes Pilot s amp Copilot s 57 11 19 45L Honeycomb Panel 8 50 5 Seat 74 54 30 41 22 15R Center Bulkhead 30 29 Web Jae e 21 00 10 64 Vertical Stiffeners Pilot s amp Copilot s Aft Attachment Angle Collective 21 00 Support Bracket Pedestal 55 14 20 00 5 06R Webs 1 10 5 Structure 73 04 30 17 3 06L 55 14 20 00 5 06R Caps Stiffeners Lower Shell 36 00 20 00 Honeycomb Panel 4 50 5 73 00 25 25 i 36 00 Inserts for cyclic and No Damage in One Set of Controls Within 73 00 20 00 Pedal Controls 3 Radius of Inserts 12 16 amp Forward Landing 14 58 Gear Attachments Two Diagonal Inserts
45. C Solvent Cleaner Naptha item 5 Appx Equivalent PROCEDURAL STEPS 1 Remove damaged skin and core Figure 4 24 Clean surface 6 inches around holes with cleaner The maximum damaged area that may be cut out is 8 inches 2 Make a patch plate as shown injFigure 4 25 Make plate 2 inches larger than cutout Lay out and drill rivet pattern 3 Completely fill void with metal set fill compound Add slight excess to allow for shrinkage 4 Apply metal set to area between the patch plate and panel Assemble to panel with 1 8 blind rivets 5 Record BDAR action taken When mission is complete as soon as practical repair the equi pment system using standard maintenance procedures OPTION 3 Damage to Both Skins and Core 2 8 Inch Only One Side of Panel is Accessible LIMITATIONS None TM 55 1520 228 BD Al RFRAME 2 MAX Figure 4 23 Damaged Honeycomb Core Panel Small Damage to One Skin and Core Figure 4 24 Damaged Honeycomb Core Panel 2 8 Inch Damage One Skin and Core MAKE PATCH FROM 2024 T3 OR 7075 T6 ALCLAD ALUMI NUM 1 8 CHERRY RIVET 2 DIA EDGE DISTANCE 4 DIA RIVET SPACING THRU ONE SKIN ONLY REPAIR PATCH AND FASTENERS AND SEALANT FILLER COMPOUND Figure 4 25 Repaired Honeycomb Core Panel 8 Inch Damage One Skin and Core PERSONNEL TIME REQUIRED el Soldier 2 Hours MATERI ALS TOOLS 1 Drill with No 30 Bit eRouter eMetal Set SITES o
46. CD Use of lead pencil in some areas will cause corrosion 2 When measuring damage use the following procedure a Use a bright color to outline each area of damage as it is a Clean all damaged areas located and recorded on the DA Form thoroughly Use brushes and swabs to 2404 Attempt to make the outline remove dirt and film from small crevices visible from all angles where damage may be present b Draw arrows on inside skin b Smooth all jagged and rough panels webs and bulkheads to point edges and be sure to cut out all radiated toward areas of damage that are hidden cracks Use largest corner radii possible in the cut outs avoid sharp corners 4 7 DAMAGE MEASUREMENT If the assessment indicates that the damage c Measure damage after should be repaired by BDAR or standard smoothing or if measuring before procedures no damage measurement is smoothing make allowance for the mad necessary Damage measurement is material which must be removed during required to determine if structural smoothing See paragraph d below repair other than cleanup can be deferred or if self recovery of the d Use a steel rule graduated damaged aircraft is feasible Damage in tenths of an inch and measure each measurement may also be required if a damage dimension to the next higher tenth BDAR repair does not restore original strength Begin damage measurement e Include the size of the with the largest damage hole when measuring damag
47. CENTER CONDUCTOR REMOVE OUTER INSULATION A REMOVE INSULATION AND SHIELD FROM COAX CABLE 1 CENTER CONDUCTOR STRIP BOTH ENDS INNER INSULATION SOLDER 52 Q RESISTOR B RADIATING ELEMENT OF ANTENNA Figure 11 45 gt TM 55 1520 228 BD ELECTRICAL AND AVIONICS SYSTEM REMOVE LOOSENED COAX CONNECTOR SHIELD PULL THROUGH i STEP B 1 TWIST THIS AREA STEP C Preparation of Coax 11 47 TM 55 1520 228 BD ELECTRICAL AND AVIONICS SYSTEM Twist the center conductor from the radiating element of the antenna to the center conductor of the coax Make a good mechanical joint and insulate with tape Ground the pigtail from the coax antenna by wrapping and twisting it around the plug where the coax was disconnected 9 Secure with tape to hold the antenna and coax in place inside the 11 48 tail Replace the structural panel and secure with screws NOTE Antenna must be at right angle 90 to aircraft skin to radiate R F energy Do not tape antenna to skin of aircraft 10 Using tape tape a one to two ounce weight below the 52 Q resistor as shown in Figure 11 47 TM 55 1520 228 BD ELECTRICAL AND AVIONICS SYSTEM STRUCTURAL PANEL GROUND PIGTAIL ANTENNA TAPE 52 Q RESISTOR fA WEIGHT yM 1 TO 2 07 Figure 11 47 Installation of Field Expedient Antenna 11 49 11 50 Blank TM 55 1520 228 BD CHAPTER 12 FU
48. FOR OBVIOUS DAMAGE DURING FLIGHT WAS AIRCRAFT DAMAGED YES NO DEBRIEF PILOT IS ANY PART OF THE GO TO STRUCTURE DAMAGED CHPT 4 NO 55 1520 228 BD ASSESSING BATTLEFIELD DAMAGE to a guide fix in this manual stan dard TM 55 1520 228 23 repair if it is feasible or a higher AVIM level of repair if extent of damage time con straint tooling requirements repair part or material and any other necessary requirements are only available at a higher level of maintenance GENERAL FAULT ASSESSMENT TABLE Refer to Table 2 2 for assessment logic flow General Assessment TS THE SYSTEM IN WORKING ORDER NO YES GO TO CHPT 18 IS ARMAMENT SYSTEM IN WORKING ORDER YES LNO VISUALLY INSPECT FOR ANY EXTERNAL DAMAGE TO THE AIRCRAFT CONTINUE ASSESSMENT TO DETERMINE IF AIRCRAFT CAN BE USED FOR MISSIONS REQUIRING ARMAMENT IS REPAIR DEFERRABLE OR FEASIBLE GIVEN THE MATERIALS TIME AND METHODS AVAILABLE DETERMINE WHETHER THE AIRCRAFT SHOULD BE RECOVERED CANNI BALIZED OR DESTROYED YES CONTINUE NEXT PAGE 2 3 55 1520 228 80 ASSESSING BATTLEFIELD DAMAGE Table 2 2 General Assessment Cont IS ANY PART OF THE ALIGHTING GEAR DAMAGED YES NO 50 70 5 IS REPAIR DEFERRABLE OR FEASIBLE GIVEN THE MATERIALS TIME AND METHODS AVAILABLE YES DETERMINE WHETHER THE AIRCRAFT SHOULD BE RECOVERED CANNI BALIZED
49. Formers Intercoastals and Channels Classify a rib former intercostal or channel as failed if any of the following conditions exist 1 Damage exceeds the limits con tained in Tables 4 2 thru 4 7 or if damage is not tabulated and exceeds 25 percent of the structural section 2 Fasteners securing the com ponent are sheared pulled through or missing in three or more adjoining loca tions 3 More than 20 percent of the total number of fasteners are similarly damaged Evaluation and Damage to Hatches Doors and Door Jambs Classify a damaged hatch door or door jamb as failed if any of the following con ditions exist 1 Damage exceeds limits tabulated Tables 4 2 thru 4 7 2 Damage to the hatch door or door jamb prevents it from being secured adequately to the airframe 3 Hinges and latches are damaged 3 and in danger of becoming unserviceable in flight 4 The hatch or door shows signs of severe overstress such as buckling or misalignment COMPONENT ae Inst e amp lot s Seat ae ure TM 55 1520 228 AIRFRAME ge Limits Forward Fuselage Condition NAMA V Table 4 2 Dama LOCATI ON ELEMENT APTFLAN FORT NT WEB SI NOTES CAUTIONS aps stiffeners D Nx Doublers 1 05 2 10 10 sass as 5 e 0 15 0 30 10 LOL Skins Webs pee sein Skin All owed Honeycomb Panel
50. May Be Damage 73 00 20 00 L amp R Center Post 73 00 20 00 3 00L Caps 3mNvadaiv 9 8 2 0291 99 NL Lv v Table 4 5 Damage Limits Forward Fuselage Condition Il Cont LOCATION DAMAGE LIMITS MEMBER ELEMENT CAP FLANGE SKIN WEB CAUTIONS _ w peo ce N w N Center Post 73 00 24 48 3 001 Side Webs and D N x CL Nxwl 87 85 72 00 3 00R Doublers 74 52 54 50 3 00L Front Web 81 30 72 00 3 00R 80 00 62 00 3 00L Splices 73 00 20 00 3 00L Stiffeners Passenger Seat 96 44 29 92 24 14L Honeycomb Seat No Damage 114 57 31 42 24 14R Panel 10 00 Within 3 of Gun Mount If Used 96 44 24 70 23 08L amp R Honeycomb Side 114 76 29 92 Panels 96 44 20 00 23 08L Honeycomb Front 45 5 29 92 23 08R Panel 96 44 20 00 23 081 Angles Side Front 114 76 29 92 23 08R Top bottom Gun Mounts 103 76 30 25 0 00 amp Fittings and Depression Stop 104 55 30 25 5 85L Honeycomb Panel No Damage Permitted Within 1 1 2 Attachment Radius of Attachments Passenger Seat 114 79 31 42 Flanges Angles 0 50 1 00 5 Back Bulkhead 122 20 72 00 Caps Splices Clips f 117 90 48 25 Web o Jem em o je ____ 115 10 35 39 17 80L Honeycomb Door 5 117 70 49 98 17 80R Assembly 114 76 31 42 200 5 117 70 49 98 Assembly i 3Nvadaiv 9 8 0 0 91 99 WL Table 4 5 Damage Limi
51. Mounts 0 00 amp Fittings and Depression Stop Honeycomb Panel No Damage Permitted Within 3 Radius Attachment 104 55 30 25 5 85L of Attachments AINVYAYIV 9 8 2 0291 99 NL r Table 4 2 Damage Limits Forward Fuselage Condition I Cont LIMITS ELEMENT CAP FLANGE SKIN WEB NOES MEMBER CAUTIONS W B op c WL Passenger Seat 79 31 42 Flanges Angles D aN x CL N x WL Back Bulkhead 122 20 72 00 Caps Splices Clips No Damage d 117 90 48 25 1 10 122 20 72 00 115 10 35 39 17 80L Honeycomb Door 117 70 49 98 17 80R Assembly 114 76 31 42 Honeycomb Panel 117 70 49 98 Assembly Bulkhead FS130 51 72 Inboard Outboard 0 30 10 Upper 72 00 Frame Caps 51 72 Frame Webs 72 00 51 72 Clips Splices 0 30 72 00 Supports Flanges Bulkhead FS130 29 70 Honeycomb Panel Lower 51 52 20 00 Honeycomb Panel 130 29 70 Aft Cabin 120 00 50 04 Inner Skin and Enclosure 130 00 69 00 20 55L amp R Doublers 117 71 50 04 Outer Skin 130 00 67 20 25 25L 117 71 50 04 Outer Skin and Door 130 00 67 20 25 25R Panel 117 71 50 00 Intercoastals 130 00 72 00 Between Inner amp 25 25L amp R Outer Skin 117 71 50 04 Angles Supports 3Nvadaiv 9 8 0 0 91 99 WL Table 4 2 Damage Limits Forward Fuselage Condition I Cont LOCATION DAMAGE LIMITS MEMBER ELEMENT CAP FLANGE SKIN WEB dS Aft Cabin 120 00 G
52. Record BDAR action taken When mission is complete as soon as practical repair the equi pment system using standard maintenance procedures OPTION 2 LIMITATIONS Repair may only be used on secondary structure to keep moisture out No damage to stiffener stringer allowed PERSONNEL REQUIRED e 1 Soldier e 30 Minutes MATERI ALS TOOLS REQUIRED e Army Green Tape item 50 or Aluminum Tape Tape Repair Appx C TM 55 1520 228 BD RFRAME 20 MINIMUM et EDGE DISTANCE t x 6D RIVET SPACING Coe uem rae ner gt x moie M TL XN SUBSTITUTE t STRINGER STIFFENER ar ow V x Y x N x Ctr FEE E r r t BO b Z MINIMUM 6 FASTENER EACH END 6D RIVET Figure 4 18 Patch Plate SPACING PROCEDURAL STEPS PERSONNEL TIME REQUIRED e 2 Soldiers 1 Smooth off ragged edges on e 2 Hours damaged skin MATERI ALS TOOLS REQUIRED 2 Tape over hole Use several e Patch Plate layers as necessary and overlap e Cherry Rivets item 38 Appx onto skin well beyond damaged area PROCEDURAL STEPS 3 Record BDAR action taken When f f mission is complete as soon as l Remove sections of the aircraft practical repair the equipment system containing the damage Smooth and using standard maintenance procedures round the cutouts Stop drill a
53. SHEET METAL SCREWS SECTION B B B Figure 6 8 Sheet Metal Plate with Sealant and or Cherry Rivets 55 1520 228 BD CHAPTER 7 ROTORS BDAR FIXES SHALL BE USED ONLY IN COMBAT OR FOR TRAINING AT THE DISCRETION OF THE COMMANDER AUTHORIZED TRAINING FIXES ARE LISTED IN APPENDIX E IN EITHER CASE DAMAGES SHALL BE REPAIRED BY STANDARD PROCEDURES AS SOON AS PRACTICABLE Section 1 INTRODUCTION 7 1 SCOPE This chapter contains the 7 3 ASSESSMENT PROCEDURES Refer to fault assessment and expedient 4 Table 1 1 procedures available to find and fi battlefield damage to the main and tail 1 4 REPAIR PROCEDURE INDEX rotor blades PARA 7 2 GENERAL The system consisting of two blade assemblies each with two Rotor Blade Hole 1 Inch blades a central hub and a control Diameter or Less mechanism The main rotor is driven by Main Rotor Blade Hole 1104 the mast which is connected to the Inches Diameter Maximum transmission and provides for fore aft lateral and vertical flight modes The tail rotor is driven Le the tail rotor gearbox and provides for directional control seel Figures 1 1 and 7 2 for system configurat Assessment proce dures are found in Mable 7 1 Section 11 REPAIRS 1 5 GENERAL The rotor system does LIMITATIONS Adjustment of blade not lend itself well to limted repairs balance may be required after repair In most instances the only repair Inspection of repaired area after eac
54. Terminal Junction 2 1021 0001 Audio Threshold 1 U92AU Jack Telephone 4 J F13E01 02 Frame Electronic 5 U94A U Plug Connector 6 U92AU Jack Telephone C 6533 ARC Control Intercom 5 C 65331 ARC Control Intercom 9 C 6533 ARC Control Intercom 10 525039 1 Switch Push 11 J F13E01 04 Rack Electronic 12 206 075 483 1 Network Impedance Matching 13 PC4D2D22 4 Connector Recepticle 14 TJ 11E02 02 Terminal Board Figure F 1 Intercom System Sheet 2 of 2 Table F 1 Wiring Table Intercom System W RE NUMBER TYPE END 1 PIN END 2 PIN C6533A 3A22 RED PRIS 1422 PR S 45422 SHI ELD 10422 SHI ELD 14A22 SHI ELD 18422 SHI ELD C6533B 3A22 RED PR S 1422 GRN PR S 45A22 SHI ELD 10 2 SHI ELD 14 2 SHI ELD 18422 SHI ELD C6533C 3A22 RED PR S 1422 PR S 45A22 SHI ELD 10 2 SHI ELD 14422 SHI ELD 18422 SHI ELD 1 Denotes PR S Pair Twisted with Shield 3 TM 55 1520 228 BD APPENDIX F J600 NOTE THIS UNIT 15 A CONTROL PANEL ONLY IN AIRCRAFT USING AN ARC 51BX TRANSMITTER Figure F 2 UHF AM Communication System Sheet 1 of 2 TM 55 1520 228 BD APPENDIX F DRAWING PART DESI GNATI ON NUMBER FUNCTI ON 1 40 01 Filter High Pass 2 Connector Electric 3 KD 59 04 Connector Plug 4 AN ARC 51BX Transceiver UHF RT 742 5 6287 ARC 51BX Control Panel AN ARC 116 AN ARC 164 6 K0 59 04 Connector Plug AS248
55. and washer screw the gasket material through the pierced hole and through the small hole on the oil tank onto the oi tank wall to stop the leak Figure 6 6 TM 55 1520 228 BD POWER PLANT 4 Replenish oil supply 5 Record BDAR action taken mssion is complete as soon as practical repair the equipment system using standard maintenance procedures When OIL TANK WALL GASKET MATERIAL SSSHO NAW METAL SCREW WASHER CLLLLL lt OOOO SA Figure 6 6 Repair Using Screw Washer and Gasket Hose Assembly OPTION 5 Sealant Nut and Bolt PERSONNEL ME 1 Soldier Hours REQUI RED MATERIALS TOOLS REQUIRED Nut Bolt and Washer Sealant Silicon item 4 Appx C or Equivalent Hose or Tubin 0 Solvent item 7 Appx Equivalent PROCEDURAL STEPS 1 Clean area around hole with solvent to remove all traces of oil so sealant will stick 6 9 TM 55 1520 228 BD POWER PLANT 2 Use a piece of hose tubing about the same diameter of the hole Assemble bolt hose tubing washer and nut Figure 6 7 Apply sealant to al edges Start nut on bolt and tubing until assembly is snug j File edge of hole until round and smooth Push hose assembly about hall way through hole Tighten nut on bolt expand hose to seal hole f necessar remove oil tank plate to allow a rendi or pliers inside of oil tank to hold nut while turning bolt NUT
56. areas must be a minimum of 8 inches apart Total damage to tail boom is not to exceed 5 percent of the tail boom area approx 100 square inches TM 55 1520 228 BD RFRAME Figure 4 29 Fracture Lacing With Safety Wire TM 55 1520 228 BD Al RFRAME LIMITATIONS None Condition 1 Inspect after every flight for damage growth PERSONNEL TIME REQUIRED e 1 Soldier Hours MATERI ALS TOOLS REQUIRED Skin Patch eCherry Rivets item 37 Appx C eEAQ3NA Adhesive item 6 App 1 PROCEDURAL STEPS 1 Remove sections of the tail boom skin containing the damage Stop drill remaining cracks Clean up damaged skin using a mini mum 0 125 inch radi us 2 DIA MIN EDGE DISTANCE 4 DIA RIVET SPACING 1 ROW RIVETS MIN Figure 4 30 2 Prepare a patch of 2024 T3 aluminum 0 050 thick and shape to contour of tail boom The patch must extend a mini mum of 3 inches forward and aft and 1 inch above and below the damaged area Figure 4 30 3 Sand surfaces lightly to remove al surface finish Clean areas with cleaner Bond patch to surface with EA934NA adhesive 4 Install a minimum of three rows of rivets running circumferentially on each end and a minimum of one row of rivets top and bottom running longitudinally in the patch size Hn t the same as skin lap joints Figure 4 30 5 Record BDAR action taken When mission is complete as soon as practical repair the equi pment system using
57. be made to contain the braided the undamaged ends with an MS union wires from unraveling Mark on tape Figure 9 14 where the cuts are to be made Hold in a vice and cut with a fine toothed 9 If a replacement section is needed hacksaw Take care to make square cut obtain replacement section and cut to Do not remove tape desired length Refer to step 1 for procedure for cutting hose No harm NOTE will be done if replacement section is too long Attach MS fittings to both If the damage is small the sides of the replacement section length of a single union may be sufficient to provide a repair 10 Place replacement section between However if the damage is longer the undamaged ends and connect the MS a replacement section will be fittings on the undamaged ends to the required fittings on the replacement section using MS unions 2 Obtain the proper sized MS fitting and unions 11 Record BDAR action taken When mission is complete as soon as 3 Slip the MS socket over one of the practical repair the equipment system undamaged ends of the hose Figure 9 12 using standard maintenance procedures Use care not to unravel the wire braids 9 11 55 1520 228 BD NIPPLE FEMALE FITTING INSERT SLEEVE BETWEEN BRAIDED COVER AND HOSE INNER HOSE Figure 9 12 Installation of Socket and Sleeve INNER HOSE BRAIDED COVER FEMALE FITTING SLEEVE Figure 9 13 Assembly of MS Fitting 55 1520 22 BD
58. breaker s to be replaced Amperage is printed on the end of reset button 4 Usd Table 11 7 to determine number of strands of No 38 AWG wire needed to replace damaged circuit breaker 5 Select strands of No 38 AWG wire to be used Strands should be 6 to 8 inches long 11 35 TM 55 1520 228 BD ELECTRICAL AND AVIONICS SYSTEM oooo88 TER ENG ENG se aus 58 Figure 11 35 11 36 COMUS FAL ALT RELAY ENCOR 115 2 ac SIG KT 6995069 CONT via RELAY ROR CONUS SOBQOO ALT WAN PLAS ADF FORCE 5 INV 5 655996 caution PNL INST LOG COLL COCKPIT POS 95959699 GENE OOOOQOO BYPASS CONT PUMP RAESE ATTO START GN UNG 02020200 TUAN MAIN ENG ENG GEICE a OH 58 C Circuit Breakers 55 1520 228 BD ELECTRICAL AND AVIONICS SYSTEM te mis of wire Hea the other end of No 38 AWG strands o 1 IN 9595 SUPPLY SIDE wire into the other terminal lug supply side Pull tight against the piece of BUSS BAR insulation and twist tight Insulate bare end of terminal lugs on both sides of 1 inch piece of insulation with tape Use 8 32 screw to connect other termina lug to bus side of bus bar CUT STRIP AND CONNECT TERMINAL LUG 0 Use this procedure to replace irc
59. control servo actuators by means of flex 9 4 REPAIR PROCEDURE INDEX hoses tubes mechanical valves and an electrically controlled solenoid 9 2 GENERAL This chapter contains field fixes applicable only to the hoses and tubing which the hydraulic system Aluminum ubing Damage TE utilizes Refer to Figure 9 2 for HE Damage 0 system fluid distribution asket 1 9 3 ASSESSMENT PROCEDURES No Hydraulic Fluid Substitutions 9 11 assessment procedures are needed to locate leaks and ruptured hoses and Section LINES AND HOSES 9 5 GENERAL c It is considered quicker to make a replacement hose using the old fitting Replacement lines may be manufac if serviceable than to repair a damaged tured in the field if materials and hose Flexible hose of braided stain tools are available less steel with rubber center is used There are two types of fittings used NOTE One fitting is a socket and nipple assembly Figure 3 3 Yr other type Never discard MS fitti they is a nipple o ring sleeve and socket 9 6 TUBE CUTTING When cutting ings are reusable The MS21922 Sleeve is not reusable b Replacement lines and hoses need tubing it is of utmost importance to not be routed along the pii of the produce a squared end free of burrs original installation hey may be Tubing may be cut with a tube cutter or routed along any convenient path as long a hacksaw The tube cutter is adaptable
60. duct routing a repair can be applied as shown at repair B Tape should extend beyond damaged area 1 to 2 inches in either direction 3 Severed duct a Using pliers and wire cutters reshape or cut away any portion of duct which would create an air flow restric tion or which is badly distorted b If area to be repaired is not in a bend portion of duct routing a repair can be applied as shown at either repair C or D If area to be repaired 15 in a bend portion of duct routing a repair can be applied as shown at either repair B or D TM 55 1520 228 BD DRIVE TRAIN SYSTEM Tape should extend beyond damaged area 1 to 2 inches in either direction 4 Record BDAR action taken When mission is complete as Soon as practical repair the equipment system using standard maintenance procedures 8 7 OIL PRESSURE TRANSMITTER LEAK CAUTION If 8 7 and 8 8 repairs are accomplished there will be no Oil Pressure Monitoring System GENERAL INFORMATION If oil is being lost due to damage at oil pressure transmitter 7 the transmitter can be removed and replaced with a threaded plug provided XMSN OIL PRESS warning light is operable and con sidered reliable LIMITATIONS Early warning of high oil pressure conditions would be eliminated since the transmission oil gauge would be rendered inoperable XSMN OIL PRESS warning light would give early warning but for low pressure conditions only PERSONN
61. eye protec tion during all operations a Remove the tape band from Semkit cartridge and pull the mixing rod straight up toward the top of the cartridge Squeeze cartridge slightly in area of the removed tape band to deform foil barrier c To mix dry filler to base com pound push mixing rod to bottom of cartridge and begin stroking in spiral clockwise motion from top to bottom of cartridge rotating mixing rod approxi mately 90 with each stroke Mix for the total number of strokes indicated on the instruction card accompanying each Semkit 40 strokes A stroke is one complete in and out cycle On last stroke mixing rod should be fully extended d Pull mixing rod out approximately one third of way e Insert ram rod into hole in top of mixing rod and inject about one third of curing agent into the cartridge CAUTI ON Use firm but even pressure Do not force tap or jolt ram rod f Repeat steps a and b until all of the contents of the rod are emptied into the cartri dge Mix curing agent into cartridge by repeating step c h Grasp cartridge firmly at neck and unscrew mixing rod by turning counter clockwise approximately three turns Remove mixing rod and discard TM 55 1520 228 BD FUEL SYSTEMS RAMROD MIXING ROD CONTAINS CURING AGENT CARTRIDGE CONTAINS BASE COMPOUND TAPE BAND DRY FILLER BOTTOM CAP Figure 12 3 Mixing Instruction for Sealant Cartridges 6 Apply adhesive
62. fied by the circuit function letter V WARNI NG AND EMERGENCY Enclosure release and locks Fire extinguishers Flare release Fire detector Intercrew buzzer or light AC POWER Wiring in the AC power system shall be identified by the circuit function letter ARMAMENT SPECIAL SYSTEMS Y A Air to air Y B Air to surface Y C Mul ti mode Y M Missile gui dance Y T Turret Armament special System number UNASSI 55 1520 228 BD ELECTRICAL AND AVIONICS SYSTEM 11 3 REPAIR PROCEDURE INDEX PARA Splicing Unshielded Wires 1 5 Wire Segments Un shi ded Wi res Terminators for Nickle Plated Shi el ds d gd Ter mi nal Boards Terminal Lugs Wire Bundle Tie Wrap 05 Coax Splice for and RG 179 B U 11 15 RG Coax Splice for RG 124 U RG 142 B U RG 302 U and RG 303 U 1 16 Section Il 11 4 GENERAL The objective of electrical and avionics system battle damage repair is to restore damaged circuits which are mission essential It is also used to make nonessential circuits safe The repair procedures in this section are designated to quickly return an aircraft to a flyable con dition a El ectri cal Electrical and and Avionics Repairs avionics equipment receiving significant battle damage wil usually not be repairable The equip ment may require replacement to meet mission requirements When replacement for nonessential
63. from Other Aircraft LIMITATIONS None PERSONNEL TI ME e 1 Soldier 10 Minutes Per Wire REQUI RED MATERI ALS TOOLS REQUIRED e Replacement Connector with Pigtai e Splices or Tape item 10 Appx B Knife PROCEDURAL STEPS 1 Obtain a replacement connector with a pigtail Replacement may be obtained from a crash damaged aircraft Cut pigtail so that splices can be staggered 2 Remove damaged connector stagger the wires being cut to remove the damaged connector The staggered wires Should match the staggered pigtail of the replacement connector of step 1 3 Splice the appropriate wires together Insulate properly 4 Record BDAR action taken When mission is complete as soon as practical repair the equipment system using standard maintenance procedures STAGGERED WIRES DAMAGED CONNECTOR Figure 11 34 11 34 Damaged Connector and Pigtail 11 21 CIRCUIT PROTECTION DEVICE REPAIR GENERAL INFORMATION Attempt to main tain a fused system at all times Circuits with damage circuit breakers can be repaired by the same non flyable or removed from other non circuits in the aircraft a Circuit breakers of rating salvaged from other aircraft essentia b Replacing circuit breakers with a specified number of individual strands of No 38 AWG wire from No 26 AWG wire OPTION 1 Replacement Salvaged Circuit Breaker LI MI TATIONS PERSONNEL TI ME None REQUI RED So
64. gear is not too badly deformed NTRODUCTI ON Replaceable steel skid shoes 7 are attached to the bottom of the skid tubes to prevent damage from contact with the ground 5 3 ASSESSMENT PROCEDURES Refer to Table 5 1 5 4 REPAIR PROCEDURE INDEX PARA Hard Landings Sudden Stops 5 6 Skid Damage s v a SKID TUBE 3 Damage to Section Figure 5 2 may be deferred unless skid tube is so deformed that alighting gear is not functional 5 6 HARD LANDINGS GENERAL INFORMATI SUDDEN STOPS a Any hard landings which per manenti y deform the crosstubes so that the spread of the skid tubes is in excess of 74 inches may cause damage to the structure transmission or rotor b Binding or unusual noises in the transmission may require replacement of rotor and the transmission This is not BDAR NOTE Aircraft grounded until assessed flight worthy 51 55 1520 228 BD ALI GHTI GEAR Skid Tube 2 Aft Crosstube 3 Forward Crosstube 4 Skid Saddle 5 Forward Crosstube Support 6 Aft Crosstube Support 7 Skid Shoes Figure 5 1 Landing Gear and Support Installation CROSS TUBE AFT CROSS TUBE Figure 5 2 Skid Tube Damage Zones Table 5 1 ALIGHTIN SUSTAINS DAMAGE TM 55 1520 228 BD ALIGHTING GEAR Assessment Procedure Logic EAR VISUALLY INSPECT DAMAGE S DAMAGE DEFERRABLE YES 15510 EVACUATE
65. install rivets between existing rivets if space permits 4 Rivet the repair parts in place using original diameter rivets or larger if necessary 5 Record BDAR action taken mission is complete as soon as practical repair the equi pment system Using standard maintenance procedures When 4 20 DAMAGE GENERAL HONEYCOMB CORE FLOOR OR PANEL NFORMATI ON a Part of the bottom shell top deck shelves interior panels and the fin panels are honeycomb core struc tures b Various repair options are given for a range of damage size OPTION 1 Small Damage to One Skin and Core or Both Skins and Core Less Than 2 Inches Maximum Di ameter LIMITATIONS Procedure is designed only to keep moisture out No additional strength has been added PERSONNEL TIME REQUIRED Soldier 15 Minutes MATERI 15 TOOLS REQUIRED Army Green Tape item 47 Appx C or Aluminized Tape PROCEDURAL STEPS 1 Remove ragged edges Figure 4 23 2 Apply tape over repair to keep out moisture TM 55 1520 228 BD Al RFRAME 3 Record BDAR action taken When mission is complete as Soon as practical repair the equi pment system Using standard maintenance procedures OPTION 2 2 to 8 Inch Damage One Skin and Core LIMITATIONS None PERSONNEL TIME REQUIRED 1 Soldier 90 Minutes MATERI ALS TOOLS REQUIRED Metal Set or Equivalent Filler Compound item 2 e Patch Plate e Cherry Rivets item 38 Appx
66. maintenance procedures AIR LINE DAMAGE 2 Cut patch from aluminum sheet metal to cover hole or other damage Patch Should extend approximately 1 inch from the edge of the hole or damage at al points if possible 3 Apply sealant around the hole area to be covered by the patch 4 Place patch in position and make Sure patch fills the contour of the i ne 5 Secure metal patch in place using hose clamp 15 7 f hose clamps are not available secure in place with safety wire Turn pigtai to line 6 aluminum tape around the repair Tape should cover at least 2 inches beyond the edge of repair 1 Record BDAR action taken When mission is complete as soon as practical repair the equi pment system using standard maintenance procedures TM 55 1520 228 BD ENVI RONMENTAL CONTROL SYSTEM Figure 15 6 Bleed Air Line Installation 15 10 TM 55 1520 228 BD ENVIRONMENTAL CONTROL SYSTEM CLAMPS TAPE HOLE DAMAGE PATCH REPAIR USING CLAMPS BLEED AIR LINE SAFETY WIRE TAPE HOLE DAMAGE PATCH REPAIR USING SAFETY WIRE Figure 15 7 Bleed Line Patch Repair 15 11 15 12 Blank TM 55 1520 228 BD CHAPTER 16 MISSION EQUI PMENT BDAR FIXES SHALL BE USED ONLY IN COMBAT OR FOR TRAINING AT THE DISCRETION OF THE COMMANDER AUTHORIZED TRAINING FIXES ARE LISTED IN APPENDIX E IN EITHER CASE DAMAGES SHALL BE REPAIRED BY STANDARD PROCEDURES AS SOON AS PRACTICABLE There are no B
67. may peel off and damage other parts of the aircraft The distance D between damage sites for most structures has a minimum required spacing The spacing requirement is expressed as a multiple factor N of the measured area of damage AI RFRAME TM 55 1520 228 BD Measuring Damage in Honeycomb Sandwich Panels Figure 4 7 1 13 TM 35 1520 228 80 RF RAME 1 The factor applies to the damage actually measured not to the maximum damage limit for the structure 2 The factor applies to the largest dimension of the largest damage between which separation is being measured 3 The factor applies only if the dimensions of both damages when added ae exceed the single damage limit 4 9 CONDITION Condition is an indi cator of the residual capacity of a damaged structural element to perform its function Battlefield damaged structures or BDAR repaired structures are classified in three conditions a Condition 1 Aircraft fully flight capable No flight restrictions However on a battlefield under the pressures of time and tactical situa tions the assessment of structural damage may not have found all the dam ages Therefore aircraft with struc tural damage whether repaired or repair deferred should be inspected after every flight The inspector should look for crack growth evidence of overstress mations cracks at growth of allowable defor and for the development of new other loca
68. must have a compatible base Table D 8 lists the primary lubricants composition as well as good additive and hydraulic fluids which are used as level Being that the purpose of lubri primary alternate and expedient uses cants and hydraulic fluids is to reduce on the QH 58 helicopter wear Support bearing loads and provide cooling their chemical composition must CAUTI ON be compatible In addition to lubri cating hydraulic fluids must transmit Lubricating oil MIL L 23699 shal power and motion If two incompatible not be used in ambient tem hydraulic fluids are mxed there is a peratures below minus 32 C 25 F tendency of a gel substance forming within the system and ruining it NOTE b Some lubricants will not with It is not advisable to mx stand 0H 58 temperatures or loads for MI L L 7808 and MIL L 23699 oils extended periods of time These type of except during an emergency If lubricants do not contain the necessary 0115 are mixed the system should base properties for withstanding long be flushed within six hours An term performance therefore they are entry on DA Form 2408 13 is recommended only as a last resort required when the oils are mixed Hydraulic oils MIL L 83282 and Expedient lubricants can cause 1 1 5606 should not be mixed one of three problems except during an emergency When these oils are mixed with each 1 They may not allow proper other or any other oil a DA Form efficient operations because of improper 2
69. of Army standard fuel or alter nate fuel When using an emergency fuel a fuel mixture which contains over 10 percent leaded gasoline is considered to be all leaded fuel When using an emergency fuel an entry on the faults and remarks column of DA Form 2408 13 Inspection Record should be made The entry should annotate the type of fuel additives and duration of operation e Fuels having the same NATO code number are interchangeable and fuels conforming to ASTM D 1655 specification may be used when standard fue MI L T 5624 P4 is not available Refer Table 0 4 TM 55 1520 228 BD APPENDIX D Table D 4 Substitute Fuels for 4 Fuel MILITARY COMMERCIAL EXPEDI ENT SPECI FI SPECI FI PRI MARY FUEL ALTERNATE FUEL FUEL CATI ON CATION Aviation Tur X bine MIL T 5624 P4 F 40 MI L T 5624 J P 5 X NATO F 44 Aviation Turbine X ASTM D 1655 Jet B Aviation Turbine X MIL T 83133 JP 8 34 Aviation Turbine X ASTM D 1655 Jet A 1 Kerosene ASTM D 3699 Kerosene X 58 MIL 6 5572 X Any AVGAS NATO F 12 F 18 F 22 D 7 TM 55 1520 228 BD APPENDIX D Table D 5 Fuels for The OH 58 Helicopter Source Primary or Standard Fuel Alternate Fuels U S Military Fuel NATO Code No P 4 MIL T 5624 P 5 MIL T 5624 8 MI L T 83133 FOREIGN FUEL PRODUCT AVIATION TYPE AVIATION AVI ATI ON DESCRI PTI ON Wide cut type High Flash T
70. onto then it is a permanent repair the primary wires of one of the cables then insert the other primary wire onto PERSONNEL TI ME REQUIRED the other end of the inner sealing 1 Soldier Sleeve and crimp with AD 1377 crimp 1 2 Hour Per Wire tool located in electrical wiring kit Refer tq Figure 11 13 MATERI 15 TOOLS REQUIRED Insulating Sleeving Heat Shrink or 4 Shrink the inner sleeve of the Tape item 49 Appx CJ Splice with temperature set at 900 F Knife Keep hot air away from shield sleeve String Nylon Braid or Tie Wrap to be used if insulating sleeve is used e 2 Sheath Connectors item 10 Appx Grounding Sheath item quei Center Conductor Splice item 10 Appx 11 18 TM 55 1520 228 BD ELECTRICAL AND AVIONICS SYSTEM SHIELD OVERLAP SHIELD OVERLAP SHIELD SLEEVE OX NY arn ROR RA RR Figure 11 14 Shielded Cable Spliced PROCEDURAL STEPS 1 If an insulating sleeve is used Slide into place and tie both ends l Select a grounding sheath Figure 11 15 step d If heat shrink is used slide into place and shrink into 2 Prepare the severed ends of the position tape is used use it to cable for application of a grounding cover repair sheath connector Figure 11 15 step a 8 Record BDAR action taken When 3 Position sheath connector and mission is complete as soon as grounding sheath as shown in Fi gure practical repair the equipment system 11 1
71. or space beyond which something may not go or is not permitted to go The route taken by a mechanical force traveling through an airframe structure A principle longitudinal fore and aft element angle or tee shape points of Support structural continuous across several Line replaceable unit electronic circuit board A point operated by AVIM units for the collection of equipment for repair A team consisting of AVUM and AVIM mechanics and technica specialist who are trained in uos Mg battle damage in addition to their routine speciality 6L05 5 TM 55 1520 228 BD GLOSSARY MAINTENANCE TEAM MT MI SSI ON FUNCTI ON COMBAT CAPABLE MF CC MODI FI CATI ON NATI ONAL STOCK NUMBER NSN NI CK OPERATI ON OPTI ON OVERHAUL PEELING PIGTAIL PITTING PRACTICE PRIMARY STRUCTURE PROCEDURE PROCESS PYLON GL05 6 GLOSSARY Cont A team consisting of organizational mechanics who may be trained assessing battle damage and field repair procedures The ability of the helicopter to performthe MINI MUM combat mission assignments An alteration and or integral change affecting the configuration of equipment or its respective parts components subassemblies or assemblies The assigned identifying number for an item of Supply consisting of the four digit Federal Supply Class FSC and the nine digit National Stock Identification Number NIIN A local break or notch in the edge of mat
72. power distribution circuits of the aircraft Replace damaged bus bars with copper or brass strips of wire of the same or higher cross sectiona area Use aluminum only when replacing aluminum bus bars since it makes unrealizable contact with other metals LIMITATIONS Repaired bus bars wil have a somewhat higher resistance than the original circuit and a higher than normal voltage drop may occur Temporary repair PERSONNEL TIME REQUIRED 2 Soldiers 2 Hours BATEN REQUI RED Drill and Bit Nuts Bolts Flat Washers Lock Washers Tape item 49 Appx C Brush Wire File Hacksaw PROCEDURAL STEPS l Cut a section of another bus bar to use for splice 2 Drill matching holes in bus bar sections and splice Figure 11 38 3 Remove insulation from bus bar only where needed Insure contact surfaces 0f cracked bus bar and splice are smooth and clean to reduce resistance necessary use tile and wire brush to dress and prepare contact surfaces 4 bolts and washers and tighte Insure no contact of bolts with structure 5 Insulate repair with tape or slit a piece of insulating tubing and wrap around the repair and tie with string 11 38 6 Same repair procedure can be used to lengthen bus bars Figure 11 Record BDAR action taken When mission is complete as soon as practical repair the equi pment system using standard maintenance procedures 11 23 BATTERY REPAIR BB 476 A GE
73. system units are not available the technician should when possible make the necessary repairs or adjustments on the unit for one more combat sortie Avionics wiring coaxial cables and general aircraft wiring can be repaired using a variety of proce dures and materials Most of these techniques are considered standard for PARA Coax Splice for RG 9 B U RG 214 U RG 225 U and R6 393 U 1 17 Coax Splice for RG 58 C U RG 233 U RG 59 B U and RG 71 B U 11 18 Component Bridging 11 19 Connector Repair 11 20 Circuit Protection Device Repair Hus ars Batter pair 176 Damaged or Defective Relays Substitute Field Expedient Emergency Antenna Typical Avionics Configuration 11 BDAR Kits 11 21 ELECTRICAL AND AVIONICS WIRING DAMAGE temporary repairs Appendix F 11515 and depicts the major components cable routes and wiring terminations for the more complex avionics systems b Isolation of Nonessential Systems To isolate damaged non essential system wiring use cri end caps tape or other insulating method Secure wires to structure c BDAR Electrical Wiring System Repair Definitions and Capabilities The BDAR wiring repair set provides for two types of aircraft electrical wiring repairs classified as PERMANENT or TEMPORARY 1 A permanent repair returns the electrical wiring system to full capabi lity as manufacture
74. to the wound opening 11 Record BDAR action taken When for a least 1 1 2 inches around the mission is complete as soon as damaged area or enough to accept the practical repair the equipment system patch cut in step 4 above using standard maintenance procedures 7 Apply and smooth out in the applied OPTION 3 Flat Panel Repair One Plane adhesive a solvent soaked fabric patch to the damaged area Apply adhesive if LIMITATIONS Inspect after every flight required to seal the patch to the tank and smooth out the surface PERSONNEL TIME REQUIRED 1 Soldier CAUTI ON 3 Hours The patch will tend to slip when MATERI ALS TOOLS REQUIRED applying additional adhesive and Knife or Scissors d Be sure to recenter o Ta van 39 or the patch quivalent item 59 App Abrasive Cloth item 1 Appx C 8 Maintain the patch position until Repair Fabric the adhesive sufficiently sets approx Adhesive item 3 Appx 30 mn NOTE Allow the adhesive to Plastic Cup or Other Small Container cure for two hours before refueling Rubber Plug Kit 9 Tighten drain valve and install PROCEDURAL STEPS cover plate L Defuel the aircraft Refer to 10 Refuel the aircraft option 1 step 1 TM 55 1520 228 BD FUEL SYSTEMS 2 step 1 of this section has been completed locate the damage wound in the tank to no more than 3 inches in diameter by using a knife or scissors Remove all frayed fabric and damaged i
75. 020 67 3040 00 024 4146 206 001 020 69 3040 00 129 6163 206 001 020 59 3040 00 129 6137 206 001 020 29 3040 00 129 6142 206 001 020 33 3040 01 006 4907 206 001 096 25 3040 00 129 6135 206 001 021 13 NOTE ALL DIMENSIONS ARE IN INCHES Table 13 3 Recommended Bolts and Drill Hole Sizes for Splice Repair LINK NOMINAL MINIMUM BOLT SIZE MAXIMUM BOLT SIZE O D FOR BOLT DRILL HOLE FOR BOLT DRILL HOLE 5 32 3 16 s4 8 3 6 7 32 7 32 9 32 1 1 2 5 16 11 32 13 32 13 11 TM 55 1520 228 BD FLIGHT CONTROLS SYSTEM BEARING ASSEMBLY p END OF BEARING ASSEMBLY THREADED END OF CLEVIS ASSEMBLY CLEVIS ASSEMBLY Figure 13 8 Control Rod with Bearing and Clevis Assemblies 13 12 55 1520 228 BD FLIGHT CONTROLS SYSTEM Figure 13 9 Flattened End of Fabricated Flight Control Figure 13 10 Corner Rounding on Fabricated Flight Control Figure 13 11 Bearing Assembly Connection of Fabricated Flight Control 13 13 55 1520 228 BD FLIGHT CONTROLS SYSTEM 7 From Table 13 2 determine the 6 Record BDAR action taken When correct distance between holes of the mission is complete as soon as flight tube Mark this distance Drill practical repair the equi pment system the hole and install the bolt using standard maintenance procedures 13 14 TM 55 1520 228 BD CHAPTER 14 UTILITY SYSTEM BDAR FIXES SHALL BE USED ONLY IN COMBAT OR FOR TRAINING AT THE DISCRETION OF
76. 1 1 September 2005 TOTAL NUMBER OF PAGES IN THIS PUBLICATION IS 762 CONSISTING OF THE FOLLOWING Page Change Page Change No No No No GOVel iron le da spese tp anl 0 D 1 through 5 11 0 vie veel 0 D 12 242 2 2 0 n 1 1 and 2 nt ue dnd 0 ipthrough DJ 0 F 1 through F 22 0 X blank 5 52 dte 0 Index 1 through index 5 0 1 1 through T S s 0 Index 6 blank 0 E 1 Glos 1 through Glos 8 0 1 7 through 1 11 0 1512 ae aan 0 2 1 thro ughi2 9 ac 0 2710 blank u itte retta 0 gel coti eis a ede add 0 3 2 0 4 1 through 4 0 0 5 1 through 5 6 0 6 1 through 6 12 0 7 1 through 7 8 0 8 1 through 8 12 0 9 1 through 9 17 2 0 9 18 blank i free d 0 jo 0 10 2 blatik ett 0 11 1 through 11 49 0 11 50 blank t e 0 12 1 through 12 9 0 12 10 blank iret 0 13 1 through 13 14 0 14 1 and 14 2 0 15 1 through 15 11 0 15 12 blank 0 TOS uires
77. 1 50L Anti Torque 3 06L Fitting Table 4 6 Damage Limits Aft Fuselage Condition LOCATION DAMAGE LIMITS MEMBER ELEMENT CAP FLANGE SKIN WEB 2 FS w Upper Longeron 130 00 72 00 14 12 Channel D N x CL D N x WL 205 00 72 93 4 72L amp R 130 00 amp EN G ER x Boom Attach Center Longeron 130 00 51 67 25 50 Angle and Channel 206 35 61 76 2 ELM ho 130 00 51 67 Spies No Damage Allowed 61 76 Tail Boom Attach Lower Longeron 130 00 29 40 22 50 Angle 0 85 192 84 44 50 1 E 113000 2940 Spie No Damage Allowed 3Nvadaiv 9 8 0 0 91 99 WL St t Table 4 6 Damage Limits Aft Fuselage Condition Il Cont DAMAGE LIMITS COMPONENT SPATIO ELEMENT CAP FLANGE SKIN WEB NOTES MEMBER CAUTIONS CD CU N wy N Aft Fuselage EN 00 LE Stiffeners D N x CL D N x WL 130 00 Lower 206 25 Longeron to Upper Longeron 130 00 Lower Doublers 206 35 Longeron 3 75 Upward 130 00 Lower Clips 206 35 Longeron Same Limits as Attaching Structure Upward Tail Boom Access 192 84 73 34 Skin 11 0 5 205 76 61 76 Deck 179 92 8 33L Skin ek EE mos as Oil Cooler 167 00 10 18L Honeycomb Support 3 00 No Damage Within 179 92 72 00 10 18R Panel 2 of Inserts 171 50 72 00 0 amp Pan amp Drain No Damage Allowed Anti To
78. 1 Wm 4 6 A713 aS CATA d gos 45 22 wt 3850 90 gas FACE K 2 5985 FRAME wes 9 wt 60 421 79 82 390 1944 Js azo 10 A VAN XN We 50045 STABILIZER i WL 205 76 31 87 HOAIZ BOOM 25 CHORD weas V N wi 44 13 WL D A 177 EXE 2 206 486 2271 97 90 074 ILONG 192 64 4 we 30 29N 1 Jj 44 NAN 1 w 20 7 WN Yeoh 25 HE wi 20 9750 o ud we 3446 gt D 5514 2l saa n 2 414 1222 ec wt 30 41 PROFILE BL BUTT LI NE CENTER TAILROTOR BEARING HANGER TANGENCY POINT FS FUSELAGE STATI ON CONTOURS N BOOM STATIONS ARE CIRCLES RADIUS AT 31 87 15 7 3555 WL WATERLINE RADIUS AT 182 405 IS 3 286 TAPER OF BOOM IS 0 02703 PER INCH BOOM BS BOOM STATION UNDERLINED STATION 15 90 TO HORIZ C BOOM Figure 4 9 Airframe Reference Lines Al RFRAME 55 1520 228 BD STA 117 71 STA 130 FS130 BULKHEAD SHEET 4 OF 5 PASSENGER SEAT BACK BULKHEAD SHEET 4 OF 5 ROOF BEAM SHEET 5 OF 5 STA 73 04 SEIS wh tus 5 B CENTER POST SHEET 3 OF 5 PASSENGER SEAT SHEET 2 OF 5 FS73 BULKHEAD SHEET 3 OF 5 PILOT AND COPILOT SEAT SHEET 2 OF 5 Cockpit Figure 4 10 4 19 TM 35 1520 228 80 RERAME 537 56 WINDSHIELD CENTER POST
79. 3 combustion heater Figure 12 44 or shroud heater system WARNING If CO indicator is noted to be 15 2 GENERAL dark turn off heater pull fire wall shut off open vents and a The three systems consists of air land as soon as practicable mxing valve air distribution ducts defroster nozzles and control switches 15 3 ASSESSMENT PROCEDURES Refer to to operate system Table 15 1 b The heat and vent system is pro 15 4 REPAIR PROCEDURE NDEX vided for crew comfort This aids the mission proficiency however the air PARA craft capability is not contingent on system operation The aircraft is fully Rigid Plastic Ducts 1585 flight capable without the system being Flexible Ducts 15 6 operable Bleed Air Lines 15 11 Section 11 RIGID PLASTIC VENTILATION DUCT 15 5 GENERAL INFORMATION Some damage PERSONNEL TI REQUIRED to plastic ducts is repairable provided 1 Soldier the time required to gain access to the e 1 Hour damaged duct is feasible MATERIALS TOOLS REQUIRED OPTION 1 Hole or Crack in Duct Rigid e Sheet Metal Patch 0 016 inch Plastic Thickness Minimum Tape Army Green a Al umi num LIMITATIONS Inspect after every flight L 590 Appx CJ 15 1 ENVIRONMENTAL CONTROL SYSTEM TM 55 1520 228 BD Bleed Air Heating and Ventilating System A amp C Figure 15 1 15 TM 55 1520 228 BD ENVI RONMENTAL CONTROL SYSTEM SEE DETAIL B MOUNTING BRACKET RE
80. 408 13 entry is required viscosity D 11 D 12 Blank TM 55 1520 244 BD APPENDIX E BDAR FIXES AUTHORIZED FOR TRAINING BDAR FIXES SHALL BE USED ONLY IN COMBAT OR FOR TRAINING AT THE DISCRETION OF THE COMMANDER AUTHORIZED TRAINING FIXES ARE LISTED IN APPENDIX E IN EITHER CASE DAMAGES SHALL BE REPAIRED BY STANDARD PROCEDURES AS SOON AS PRACTICABLE REPAIR PROCEDURE PARA NO RFRAME Honeycomb Core Floor or Panel Damage 4 22 DRIVE TRAIN SYSTEM Air Duct Hose e HYDRAULIC SYSTEM Lines and 11265 2 oad et xoa o s r ed Rm 314 Aluminum Tube Damage o a a a aa Hydraulic Hose Damage Pu ue RR ELECTRICAL AND AVIONICS SYSTEM Splicing Unshielded Wires Damaged Wire Insulation Shielded Cable Repair Shielded Cable Repair Segments Shielded Terminators Terminators for Nickel Plated Shields including vermi llion Terminal Boards Terminal Lugs Wire Bundle Tie Wraps Coax Splice for RG 13610 and RG 179 n Bus Bars T Battery Repair 476 Substitute Emergency Antenna Field Expedi ent TM 55 1520 228 BD APPENDIX E BDAR FIXES AUTHORIZED FOR TRAINING Cont REPAIR PROCEDURE PARA NO FLIGHT CONTROL SYSTEM Tubes Eliane Control s s lt xc eca Aw odd Q a 13 4 ENVIRONMENTAL CONTROL SYSTEM Rigid Plastic Ventilation Duct 15 5 Flexible Duct Damage oom Ble
81. 5 step b NOTE Crimp sheath con using standard maintenance procedures nector and grounding sheath only at one side at this ti me OPTION 3 Pigtailed Sheath Method 4 Slide insulating sleeve over LIMITATIONS This is a temporary uncrimped sheath connector as shown in repair Figure 11 1p step b NOTE If insu lating sleeve is not available use heat PERSONNEL TIME REQUI RED Shrink or alternate insulation such as 1 Soldier electrical tape e 1 2 Hour Per Wire 5 Splice center conductor using a per MATERI ALS TOOLS REQUIRED manent splice or by using one of the e Knife splicing procedures in paragraph 11 9 insulating Sleeving or Tape item 49 Appx C 6 Push the free end of the grounding e String Nylon Braid or Tie Wrap to wire into the uncrimped grounding sheath be used if insulating sleeve is used connector Crimp securely Figure 11 15 Center Conductor Splice step item 10 B 11 19 55 1520 228 80 ELECTRICAL AND AVIONICS SYSTEM GROUNDING SHEATH CONNECTOR INSULATING SLEEVE FIRST CRIMP E RS SON COC SPLICE SECOND CRIMP STEP C INSULATION cola Ses BS TIE WITH TWINE AT BOTH ENDS STEP D Figure 11 15 Shielded Cable Repair 11 20 TM 55 1520 228 BD ELECTRICAL AND AVIONICS SYSTEM PROCEDURAL STEPS Shielding must be long enough to overlap the shielding on both sides of the cable 1 Prepare s
82. 5 6 Flight Controls System Subsystems and Assemblies e lt lt lt lt wee 13 4 Frame Bulkhead Skin and Stringer Damage 4 19 Fuel Cell Repait a i s s 12 1 Fuel Line Repair 9 9 9 9 9 8 Fuel Substitutions 9 9 9 9 9 9 9 9 12 6 G General Fault Assessment Tables s s s s s ee ew we gt 2 2 H Hard Landings Sudden Stops es s s ww s 3 6 Honeycomb Core Floor or Panel Damage 4 20 Hose and Line Replacement 9 1 Hydraulic Fluid Substitutions c E 9 11 Hydraulic Hose Damage ee ee ee Lt SSS S 9 8 NDEX 2 55 1520 228 BD NDEX INDEX Cont Subj ect Paragraph Initial Assessment Airframe 2 2 2 2 2 4 5 J K Lines and Hose Replacement rur EIU 9 5 Low Pressure Sensing Switch ke cont oe Se E Gee GS 0 0 Lubricants and Hydraulic 0 6 Main Rotor Blade Hole 1 to 4 Inches Diameter Maximum lt Manner of Blending 0 5 N 0 011 Hoses and Lines Leaks or Restriction hu 4 d 0 9 Oil Lines Rigid Type Repair 2 9 1 Oil Pressure Transmitter Leak 8 1 011 Tank Punctured ao the Ay
83. 51764422 5765422 5768422 5803422 5804422 5817422 X818A22 54820A20 54821422 54822122 54823422 54825A20 54826422 54834A20 5484942 SAT01A 9 7018 SX828A SX829A SX830A SX831A TM 55 1520 228 BD APPENDIX F APX100 5048A22 WHT 5048A22 BLU 50014 APX100 5002A APR39 31 SHI ELD APX100 5017A COAX 5018A COAX 5019A COAX 100 5020A COAX 1 Denotes PR S Pair Twisted with Shield TM 55 1520 228 BD APP ENDIX F DRAWI NG PART DESI GNATI ON NUMBER FUNCTI ON 1 AS 2892 APR 39 V Antenna Left Spiral 2 Indicator Radar Signal 3 AS 2891 APR 39 V Antenna Right Spiral 4 AS 2892 APR 39 V Antenna Left Spiral j R 1838 APR 39 Receiver Radar 6 5 2890 APR 39 V Antenna 1 CM 440 APR 39 V Comparator 8 C 9326 APR 39 V Control Detecting Signal 9 5 2891 39 1 Antenna Right Spiral 10 8 1838 APR 39 V Receiver Radar Figure F 10 Radar Warning System AN APR 39 TM 35 1520 228 80 APPENDIX F Table F 11 Wiring Table AN APR 39 W RE ENDI 3422RE1 3422RE2P3 3422RE2P4 3422RE1P4 3422E1P1 342271P1 3422RE1 1 1 3422RE1P4 30422 1820 30822 21022 APR39 m 3422RE1 3422RE2P3 3422RE2P4 3422RETP4 34227192 342271P1 APR39 314 1 1 3410TR1P1 55 1520 228 BD INDEX Subject Paragraph A Application BDAR ae ee eee 1 3 Allowable Damage
84. 520 228 80 CHAPTER 11 ELECTRICAL AND AVIONICS SYSTEM BDAR FIXES SHALL BE USED ONLY IN COMBAT OR FOR TRAINING AT THE DISCRETION OF THE COMMANDER AUTHORIZED TRAINING FIXES ARE LISTED IN APPENDIX E IN EITHER CASE DAMAGES SHALL BE REPAIRED BY STANDARD PROCEDURES AS SOON AS PRACTICABLE Section 1 NTRODUCTI ON 11 1 SCOPE This chapter provides It is used to distinguish between wires methods for assessing battle damage in the same circuit The wire segment deferring damage repair and repairing letter is used to distinguish between electrical and avionics systems conductor segments a wire segment be Extensive repairs to complicated com tween two terminals or connections The ponents or line replaceable units LRUs wire size number is used to identify the are not expected to be made in the gage of the wire or cable The ground field Therefore more emphasis is phase or thermocouple letter s are placed on common repairs to intercon used as suffixes to the wire identifi necting cables and simple electrical and cation code to further identify certain avionic components wires Ground wires are identified with an N suffix Phase letters A or 11 2 ASSESSMENT PROCEDURES are added to identify the phase of wires See Table 11 11 assessment logic that are in the three phase wiring of alternating current AC systems For a Wire Identification The most thermocouple wire the following suffixes difficult and time co
85. 55 55 ment and expedient repair procedures for the OH 58 helicopter airframe The procedures are to be used only during combat operations or during periods of extreme emergency a Section I contains information pertaining to the various structural areas which are suspected of being damaged and whether the damage is to a primary or secondary element Logic flow chart tables and damage limit tables are also part of this section b Section II consists of expedient structural repairs and procedures on how to perform these repairs and field fixes 4 2 ASSESSMENT PROCEDURES Table 4 1 4 3 GENERAL Aircraft structure is classified as primary and secondary structure Refer to a The primary structure is the basic structure which holds the aircraft together Any serious damage to any element of the primary structure will restrict the combat capability of the aircraft The primary structure for each major airframe subassembly is shown in Sheets 1 thru 5 b Secondary structures are mounted on the primary structure No amount of structural damage to secondary struc tures will restrict combat capability from a structural point of view INTRODUCTION however secondary structure may be required for aerodynamic reasons or to accomplish or support mission functions 4 4 STRUCTURAL DAMAGE ASSESSMENT AND REPAIR The battlefield structural damage assessment and repair consists of three steps an initial ass
86. 6 61 76 Deck 179 92 8 33L mE UL 205 76 72 00 8 33R Oil Cooler 167 00 10 18L Support wa ms Damage 179 92 10 18R Panel Within 3 of 72 00 r 17150 7200 0 Pan amp Drain No Damage Allowed 9 8 2 0291 99 NL 46 7 Table 4 3 Damage Limits Fuselage Condition Cont LOCATION DAMAGE LIMITS COMPONENT um MEMBER ELEMENT CAP FLANGE FLANGE SKIN WEB WEB GAUTIDNS Fo e n fm w Anti Torque Support 179 92 58 27 Support and Fittings D Nx CL D Nx WL pamm 181 62 73 37 Re Damage Aled mm ER pee sss pei ewm 1 z pepe D zs am lee ep L 130 00 51 67 15 00L amp R Web 4 75 5 192 84 59 98 7 00L amp R Shear Web 192 84 7 00L amp R Stiffeners 192 84 7 00L amp R Webs 3 00 5 206 35 60 00 4 00L amp R Electrical 130 00 29 47 ee Damage Allowed to One Insert Compartment Floor 167 00 34 46 in Each Group of Four 130 00 29 47 No Damage Within 167 00 34 46 10 00 2 of Effective Inserts Bulkheads 142 154 167 EE Section __ ozs 15010 142 154 167 Stiffeners Clips Choe 179 192 No Damage Allowed 3Nvadaiv 9 8 0 0 91 99 WL 8 Table 4 3 Damage Limits Fuselage Condition Cont DAMAGE LIMITS COMPONENT LOCATION NOTES MEMBER ELEMENT
87. 6 3 00R Doublers ELEMENT 120 90 80 46 3 00L Bottom Skin and Access 130 00 67 92 3 00R Cover Lower Cabin Shell 73 18 20 00 18 40L amp R Radius and Edge of 113 00 25 25 Outboard Honeycomb Panel 73 18 18 40L Honeycomb Panel 113 00 20 00 18 40R 113 00 20 00 Honeycomb Panel 130 00 54 65 36 00 20 00 Frames Angles Stiffeners 075 130 00 54 65 3 00 Upper Cabin Roof 54 48 Top Skin Shell 82 86 82 86 Honeycomb Panels 125 00 120 40 14 12L amp R Honeycomb Panels 3 00 5 130 00 Outboard 125 00 14 12L Titanium Panel l 130 00 14 129 ae ee r l 54 48 Flanges Formers 7 1 130 00 1 1 Stiffeners Supports esejs Landing Gear 73 00 amp 18 30 amp 13 30L amp R amp Support Fitting Flanges 73 008 18 308 13 30L amp R Back Up Support 3Nvadaiv 9 8 0 0 91 99 WL Table 4 5 Damage Limits Forward Fuselage Condition Cont LOCATION DAMAGE LIMITS MEMBER p ELEMENT CAP FLANGE SKIN WEB MONS Landing Gear 73 008 18 30 amp 13 30 8 Attachment Fasteners D N x CL DENxWL 130 00 20 75 amp and Inserts 10 25L amp R Damage Allowed on One Fastener and Insert Per Fitting Jacking amp Tiedown Fitting Damage Limited By Jacking and Tiedown Fittings Requirements Anti Torque 5 04L Fitting Support 35 66 2100 304 n Alowed Damage Allowed Collective Fitting Jackshaft Bearing No Damage Allowed Support 73 12 28 62
88. 7 Antenna UHF 8 KA 59 119 Connector Plug Electric Figure F 2 UHF AM Communication System Sheet 2 of 2 Table F 2 Wiring Table UHF AM Communication System ARC51 124A20 125A20 128420 RED 129420 131420 140A ARC116 10A22 101A 1018 SAME WIRING USED FOR AN ARC 164 ARC116 10B22 RED 11822 BLK 101A 1018 1 Underlined Pin Numbers Denote Lower Case 2 PR S Pair Twisted with Shield TM 55 1520 228 BD APPENDIX F Figure 3 VHF AM Communication System and Connecting Cables Sheet 1 of 2 F 6 TM 55 1520 228 BD APPENDIX F DRAWI NG PART DESI GNATI ON NUMBER FUNCTI ON 1 KC 59 212 Connector Plug 2 40 03 Filter Band Pass 3 TO6RE18 325 Connector Plug 4 KC 59 212 Connector Plug 5 0 59 04 Connector Plug 6 AN ARC 115 Connector Plug 7 KC 59 196 Connector Plug 8 KC 59 198 Connector Electric 9 KC 19 120 Connector Electric Figure 3 VHF AM Communication System and Connecting Cables Sheet 2 of 2 Table 3 Wiring Table VHF AM Communication System WIRE NUMBER TYPE END T PIN END 2 m OH 58A E ARC115 10A22 SHI ELD 101A COAX 1018 COAX ARC115 101C COAX OH 58C ARC115 10B22 RED 11822 BLK 101 1018 115 101 F1 55 1520 228 BD APPENDIX F RAWI NG 0 DESI GNATI ON 55 ID cn CO r2 L3 10 1 1 13 PART NUMBER LPF 40 028 204 075 850
89. 84 Helicopter Observation NSN 1520 00 169 7137 0H 58C Helicopter Observation NSN 1520 01 020 4216 55 1520 228 WARNING DATA Personnel performing operations procedures and practices which are included or implied in this technical manual shall observe the general following warnings Disregard of these warnings can cause serious injury or death WARNINGS FLIGHT SAFETY The standards contained herein allow aircraft to be flown with battle damage Substantially in excess of peacetime limits Under no circumstances shall this manual be used entirely or in part for peacetime maintenance of the aircraft Assessment of aircraft battle damage requires extreme care and diligence and strict adherence to the instructions and standards contained in this manual If at any Stage of damage assessment the assessor believes that oversights or errors have been made the assessment shall be stopped at that point and repeated from the beginning Under no circumstances shall the requirements of this manual be waived or circumvented without the express approval of the commander or his designated representative EXPLOSIVES Battle damaged areas should be inspected for unexploded ordnance before attempting repairs Disposal of unexploded ordnance should be accomplished by qualified personnel ARMAMENT Loaded weapons or weapons being loaded or unloaded shall be pointed in a direction which offers the least exposure to personnel or property in the event
90. ABLE OR FEASIBLE GIVEN THE MATERIALS TIME AND METHODS AVAILABLE YES DETERMINE WHETHER THE AIRCRAFT SHOULD BE RECOVERED CANNI BALIZED OR DESTROYED ONTINUE NEXT PAGE 2 1 2 8 55 1520 228 BD ASSESSING BATTLEFIED DAMAGE Table 2 2 ARE THE INSTRUMENTS AND PANELS DAMAGED IS THE ELECTRONIC AND ELECTRICAL SYSTEM UNDAM AGED AND FUNCTIONING 0 TO CHPT 11 IS THE FUEL SYSTEM IN WORKING ORDER NO GO TO CHPT 12 CONTINUE NEXT PAGE General Assessment Cont GO TO CHPT 10 IS REPAIR DEFERRABLE OR FEASIBLE GIVEN THE MATERIALS TIME AND METHODS AVAILABLE NO DETERMINE WHETHER THE AIRCRAFT SHOULD BE RECOVERED CANNI BALIZED OR DESTROYED IS REPAIR DEFERRABLE OR FEASIBLE GIVEN THE MATERIALS TIME AND METHODS AVAILABLE NO DETERMINE WHETHER THE AIRCRAFT SHOULD BE RECOVERED CANNI BALIZED OR DESTROYED 15 REPAIR DEFERRABLE OR FEASIBLE GIVEN THE MATERIALS TIME AND METHODS AVAILABLE NO DETERMINE WHETHER THE AIRCRAFT SHOULD BE RECOVERED CANNI BALIZED OR DESTROYED 55 1520 228 ASSESSING BATTLEFIELD DAMAGE iu 1 Table 2 2 General Assessment Cont IS THE FLIGHT CONTROL SYSTEM IN WORKING ORDER 15 REPAIR DEFERRABLE OR FEASIBLE GIVEN THE MATERIALS TIME AND METHODS AVAILABLE TO 13 DETERMINE WHETHER THE AIRCRAFT SHOUL
91. ALS PARTS BDAR TRAINING PROCEDURES AVI ONI 5 CONFIGURATION LIST OF ILLUSTRATIONS Figure Title DA Form 2408 13 DA Form 2408 18 Tm Damage Assessment Nar kings sheet 1 of 3 Aircraft Sections Wr 2 DA Form 2404 TN Evaluating Damage to Angl es Channel 5 and Z Angles Damaged Cross Section lt Measuring Skin Panel Damage Measuring Damage in Webs and Panels Measuring Damage in Sandwich Panels 0H 58 Helicopter Airframe Reference Lines Cockpit Fuselage Pylon Support Structure sheet 1 of 5 Upper and Lower Shell Structure Aft Fuselage Structure Tall Boom pb ou Cowling and Firewalls ET Typical Former Repair sheet 1 of 2 Cutout in Damage Skin Patch Plate Typical Patch Plate Repair Expedient Cap Longeron Repair Repair of Damage Bulkhead Flange Typical Combination Repair Sheet 1 of 2 55 1520 228 BO Figure 4 23 LIST OF ILLUSTRATIONS Cont Title Damaged Honeycomb Core Panel Small Damage to One Skin and Core Damaged Honeycomb Core Panel 1 8 Inch Damage One Skin and Core oe Repaired Honeycomb Core Panel 2 J nch Damage One Skin and Core IP Damaged Repair Accessible One Side Only Patch Plates One Side Accessible Repair Repair of Honeycomb Core Panel Damage Over 8 Inches Both Skins and Core Fracture Lacing with Safety Wire Tail Boom Skin Damage
92. AND BOLT SEALANT Figure 6 7 1 df oil reinstall tank plate was removed 5 After sealant has dried replenish oil Supply 6 Record BDAR action taken When mission is complete as soon as practical repair the equi pment system Using standard maintenance procedures OIL TANK WALL SEALANT PIECE OF HOSE Hose Assembly Sealant Nut and Bolt OPTION 6 Sheet Metal with Sealant and or Blind Rivets for large holes PERSONNEL TIME REQUIRED Soldiers 3 Hours MATERI ALS TOOLS REQUIRED Sheet Metal Sealant Silicon item 4 Appx C or Equivalent Blind Rivets or Sheet Metal Screws Td 7 Appx C 4 item 20 Appx PROCEDURAL STEPS 1 Cut a piece of sheet metal that will overlap the hole by 1 1 2 inches at all points Faure 620 55 1520 228 BD POWER PLANT 2 f sealant is to be used clean area around hole with solvent so sealant will sti ck 3 Put sealant or gasket material over hole Put sheet metal plate over hole and secure with sheet metal screws or blind rivets 4 After sealant has dried replenish oil supply 5 Record BDAR action taken When mission is complete as soon as practical repair the equipment system using standard maintenance procedures TM 55 1520 228 BD POWER PLANT A HOLE SHEET METAL PLATE OIL TANK WALL EPOXY SEALANT pee SECTION A A SHEET METAL PLATE WITH EPOXY topMV h aN r RIVETS BLIND OR
93. AREA POSITION TOP PLATE OF REPAIR CLAMP AND HAND TIGHTEN WING NUT CAUTION MECHANICAL TIGHTENING OF WING NUT CAN RESULT IN CLAMP FAILURE Figure 12 2 Emergency Mechanical Clamp Repair TM 55 1520 228 BD FUEL SYSTEMS 6 Refuel the aircraft 7 Record BDAR action taken When mission is complete as soon as practical repair the equi pment system using standard maintenance procedures OPTION 2 Adhesive Repair LIMITATIONS Tempora i 100 ns flight hour capability pect after every flight PERSONNEL TIME REQUIRED 1 Soldier 3 Hours REQUIRED Knife Solvent 1 1 1 1 or Equivalent item 59 Appx Repair Fabric Abrasive Cloth ji tem CI Adhesive item 3 Appx Plastic Container Cup Wooden Tongue Depressor item 60 Appx C PROCEDURAL STEPS Refer to L Defuel the aircraft option 1 step 1 2 Once step 1 above has been completed locate the damage Trim only the outer exposed damage area to provide a reasonably smooth exterior surface DO NOT ENLARGE HOLE 3 Abrade and solvent wash the area Surrounding the damage Clean at least 4 inches beyond the damage 4 Cut a fabric patch to overlap the damaged area by a minimum of 1 inch all the way around Soak the patch in solvent NOTE No hole is required in the center of the patch 5 Mix the adhesive as described below in steps 5a thru 5h refer to Figure 12 3 CAUTI ON Wear goggles or other
94. Coax Splicing w s s s s s s s s s s s s s 9 s s 11 15 thru 11 18 Component Bridging aa 295 11 19 Condition Airframe 2 2222 lt e e s a s s s s e s s s s e 4 9 Connector 11 20 NDEX 1 TM 55 1520 228 8 INDEX INDEX Cont Subject Paragraph D Damage Measurement Airframe e s ew s s eee s e s s s ewe 9 4 7 4 12 Damaged or Defective Power RES 1 4 11 24 Damaged Wire Insulation S te ew ee es ve Definitions wth x0 Neue ESD Description Power Plant o 5 n 6 1 Detail Assessment Airframe 9 s s e s s s s 9999 1 6 Valve or Control Repair 14 4 Drive Train Component Damage 1 6 5 Drive Train Damage p de 4 8 2 Double Check Valve noperati ve 444 s s s s s e s s t nm 9 6 6 Emergency Equipment Description Emergency Equipment 19 1 Supplementary Emergency Equipment Information lt e eee 19 2 Environmental Control System Bl eed Air Line Damage i i A 9 15 1 Flexible Duct Damage ee ee s 15 6 Rigid Plastic Ventilation EORUM dU abl o 15 5 F Flexible Duct Damage 2 4 1
95. D BE RECOVERED CANNI BALIZED OR DESTROYED ARE THE UTILITY AND ENVIRONMENTAL CONTROL UNIT SYSTEMS OPERATING 15 REPAIR DEFERRABLE OR FEASIBLE GIVEN THE MATERIALS TIME AND METHODS AVAILABLE GO TO CHPT 14 15 THE MISSION EQUIPMENT PRESENT AND IN SOUND CONDITION DETERMINE WHETHER THE AIRCRAFT SHOULD BE RECOVERED CANNI BALIZED OR DESTROYED 15 REPAIR DEFERRABLE OR FEASIBLE GIVEN YES MATERIALS TIME AND METHODS AVAILABLE DETERMINE WHETHER THE AIRCRAFT SHOULD BE RECOVERED CANNI BALIZED OR DESTROYED TOP BDAR ASSESSMENT 9 2 10 Blank 55 1520 228 BD CHAPTER 3 GENERAL REPAIRS BDAR FIXES SHALL BE USED ONLY IN COMBAT OR FOR TRAINING AT THE DISCRETION OF THE COMMANDER AUTHORIZED TRAINING FIXES ARE LISTED IN APPENDIX E IN EITHER CASE DANAGES SHALL BE REPAIRED BY STANDARD PROCEDURES AS SOON AS PRACTICABLE No general repairs have been identified Chapters 4 thru 19 for functional group for this model helicopter Proceed to assessment and repair procedures 3 1 3 2 Blank 55 1520 228 BD CHAPTER 4 AIRFRAME BDAR FIXES SHALL BE USED ONLY IN COMBAT OR FOR TRAINING AT THE DISCRETION OF THE COMMANDER AUTHORIZED TRAINING FIXES ARE LISTED IN APPENDIX E IN EITHER CASE DAMAGES SHALL BE REPAIRED BY STANDARD PROCEDURES AS SOON AS PRACTICABLE Section I 4 1 SCOPE This chapter contains information on battle damage
96. DAR repairs offered for the mission equi pment 16 1 16 2 Blank TM 55 1520 228 BD CHAPTER 17 EMERGENCY EQUI PMENT BDAR FIXES SHALL BE USED ONLY IN COMBAT OR FOR TRAINING AT THE DISCRETION OF THE COMMANDER AUTHORIZED TRAINING FIXES ARE LISTED IN APPENDIX E EITHER CASE DAMAGES SHALL BE REPAIRED BY STANDARD PROCEDURES AS SOON AS PRACTICABLE There are no BDAR repairs offered for the emergency equipment 17 1 17 2 Blank TM 55 1520 228 BD APPENDIX A REFERENCES AT THE DI SCRETI ON OF THE COMMANDER AUTHORIZED TRAINING FIXES ARE LISTED IN APPENDIX E IN EITHER CASE DAMAGES SHALL BE REPAIRED BY STANDARD PROCEDURES AS SOON AS PRACTICABLE The following references of the issue in effect are required for use by repair personnel to accomplish the instructions set forth in this TM PUBLI CATI ON NUMBER TITLE DA 738 751 es Functional User s Manual for the Army Mainte nance Management Systems Aviation 5 FM 350 NBC Decontamination TM 55 1500 3928 25 Aeronautical Equipment Maintenance Management Policies and Procedures Operator s Manual Army Model OH 58A C Helicopter Aviation Unit and Intermediate Maintenance Manual IM 55 1520 228800 uo wwe Operator s and Crewmember s Checklist 71 1 A 2 Blank TM 55 1520 228 BD APPENDIX 8 SPECIAL OR FABRICATED TOOLS BDAR FIXES SHALL BE USED ONLY IN COMBAT OR FOR TRAINING AT T
97. DE HOLE ONE INCH DIAMETER OR LESS PER SEC II MAIN ROTOR BLADE ONE INCH TO FOUR INCHES DIAMETER MAX PER SEC II 1 4 TM 55 1520 228 BD ROTORS gt SPAN MAIN ROTOR BLADE STRUCTURALLY SENSITIVE AREA LEAST TOLERANCE TO DAMAGE HONEYCOMB CORE AREA MOST TOLERANT TO DAMAGE TAIL ROTOR BLADE Figure 7 3 Rotor Blades Damage Sensitive Areas TM 55 1520 228 BD ROTORS 2 Smooth damage remove all rough edges 3 Clean area around damage and completely around blade where tape 15 to be applied 4 Cover hole with a chordwise layer of tape top and bottom of blade Extend ends of tape 2 inches beyond area of damage Figure 1 4 5 Wrap a second layer of tape chord Wise over the first layer and around the entire blade Overlap ends by 3 inches with outside edge of top toward trailing edge exact number of tape wraps on opposite side at approximately same span locati on 7 Record BDAR action taken When mssion is complete as soon as practical repair the equipment system Using standard maintenance procedures 1 7 MAIN ROTOR BLADE INCHES DIAMETER MAXI MUM GENERAL INFORMATION A medium size hole in the honeycomb core area Fi gure 7 3 of a main rotor blade can be tem porarily repaired by fashioning a patch HOLE 1 T0 4 using aluminum foil as a plugging material Removal of blade is not necessary This repair is limited to certain areas of the blade as s
98. E SIGNATURE AUTOVON PLUS EXTEN SION 788 1234 DA FORM 2028 FEB 74 REPLACES DA FORM 2028 1 DEC 68 WHICH WILL BE USED USAPA V3 01 MSG Jane Q Doe SFC TO Forward direct to addressee listed in publication FROM Activity and location Include ZIP Code DATE Commander U S Army Aviation and Missile Command MSG Jane Q Doe 8 30 02 ATTN AMSAM MMC MA NP 1234 Any Street Redstone Arsenal AL 35898 Nowhere Town AL 34565 PART REPAIR PARTS AND SPECIAL TOOL LISTS AND SUPPLY CATALOGS SUPPLY MANUALS pU NUMBER p TITLE TOTAL NO PAGE COLM LINE NATIONAL STOCK REFERENCE FIGURE oF MAJOR NUMBER ITEMS SUPPORTED 4 PART Ill REMARKS Any general remarks blank form bla v TYPED NAME GRADE OR TITLE TELEPHONE EXCHANGE AUTOVON SIGNATURE PLUS EXTENSION MSG Jane Q Doe SFC 788 1234 USAPA V3 01 Use Part Il reverse for Repair Parts Spe RECOMMENDED CHANGES TO PUBLICATIONS AND cial Tool Lists RPSTL and Supply Catalogs BLANK FORMS Supply Manuals SC SM For use of this form see AR 25 30 the proponent agency is ODISC4 TO Forward to proponent of publication or form Include ZIP Code FROM Activity and location Include ZIP Code Commander U S Army Aviation and Missile Command ATTN AMSAM MMC MA NP Redstone Arsenal AL 35898 PART 1 ALL PUBLICATIONS EXCEPT RPSTL AND SC SM AND BLANK FORMS PUBLICATION FORM NUMBER DATE TITLE
99. EL SYSTEM BDAR FIXES SHALL BE USED ONLY IN COMBAT OR FOR TRAINING AT THE DISCRETION OF THE COMMANDER AUTHORIZED TRAINING FIXES ARE LISTED IN APPENDIX E IN EITHER CASE DAMAGES SHALL BE REPAIRED BY STANDARD PROCEDURES AS SOON AS PRACTICABLE Section l 12 1 GENERAL a The fuel supply system 12 1 consists of a crashworthy bladder type self sealing cell The fuel cell is designed to fit under the passenger seat in the floor cavity of the fuse lage The system s fuel flow lines are self sealing The rigid lines are used for fuel flow or as vent lines The fuel boost pump is the cartridge type which can be replaced without defueling b The fuel tank will self seal when damaged by small arms projectiles up to 50 caliber Damage to the tank and the Section 11 12 4 GENERAL Replacement lines and hoses need not be routed along the path of the ori ginal installation They may be routed along any convenient path as long as they do not interfere with personnel or with operating equipment Long lines and hoses should be clamped to hard sup ports at convenient intervals not exceeding 24 inches b Tubing in the 0H 58 fuel system is limited to the fuel vent line When damage occurs to any of the lines tubes or hoses they may be substituted with a flexible type hose from the kit c If hose assemblies from the kit are not available damage may be cut out and replaced with a small se
100. EL TI ME REQUIRED 1 Soldier 15 Mi nutes MATERI ALS TOOLS REQUIRED Pliers Open End Wrench Tie Wraps p Plug MS24391D4L same as 7 Refer to Figure 6 2 lock wire at PROCEDURAL STEPS l Cut transmitter 7 2 Remove electrical connector from transmitter 7 j Remove transmitter 7 and packing Retain packing TM 55 1520 228 BD DRIVE TRAIN SYSTEM 1 Filler Cap 9 Oil Filter 2 Oil Cooler 10 Oil Filter Head Assy j Transfer Tube 11 Filter Bypass Valve 4 Nozzle Jet 12 Oil Temperature Switch 5 Pressure Regulating Valve 13 011 Pump 6 Hoses and Lines cj 14 Chip Detector 7 Oil Pressure Transmitter C 15 Chip Detector 4 16 Air Duct Hoses 8 Low Pressure Sensing Switch Figure 8 2 External Components Transmission Oi System 0 0 TM 55 1520 228 BD DRIVE TRAIN SYSTEM TAPE WRAPPED AROUND REPAIR A STRIPS OF TAPE OVERLAP TO SPAN DAMAGED AREA DAMAGE SPAN 6 INCH MAX TAPE WRAPPED AROUND REPAIR B Figure 8 3 Flex Duct Repair Sheet 1 of 2 TM 55 1520 228 BD DRIVE TRAIN SYSTEM THIN PLIABLE MATERIAL SPANS DAMAGED AREA DAMAGE SPAN x TAPE WRAPPED AROUND REPAIR C NEW OR USED a FLEX DUCT PIECE FLEX DUCT SPANS DAMAGED AREA TAPE WRAPPED AROUND DAMAGE SPAN TAPE WRAPPED AROUND REPAIR D Figure 8 3 Flex Duct Repair Sheet 2 of 2 8 10 TM 55 1520 228 BD DRIVE TRAIN SYSTEM 4 Install plug and p
101. EQUIRED on the opposite side the transmission 1 Soldier does not bind and there is no oil loss 15 Mi nutes repair may be deferred Aircraft is fully flight US Other repairs that MATERIALS TOOLS REQUIRED may be utilized for the EE can Pliers be found in Chapter 6 Section He Waps Open End Wrench LIMITATIONS Small oil loss can be Plug MS 24391D4L same as 7 tolerated Inspect after every flight REQUI RED PROCEDURAL STEPS Refer to Figure 8 2 1 Soldier 15 Minutes l Cut lock wire MATERI ALS TOOLS REQUIRED 2 Remove electrical connector from Solvent Cleaner item 7 Appx Switch 8 Tape Ar my Green item 50 Appx or Equivalent j Remove switch 8 and packing Plug Retain packing Safety Wire item 26 Appx C TM 55 1520 228 BD DRIVE TRAIN SYSTEM PROCEDURAL STEPS 1 Clean damaged area with solvent 2 Close bullet hole with a plug and hold in place with tape 3 Secure plug in place with safety Wi re NOTE Because transmission is pressur ized try to center safety wire over plug 4 Fill transmission with oil 5 Inspect after every flight 6 Record BDAR action taken mission is complete as soon as practical repair the equi pment system using standard maintenance procedures 8 11 TAIL ROTOR GEARBOX GENERAL INFORMATION If a bullet strikes the gearbox and exits and the gears do not jam bind or lose lubricant repair may be deferred
102. ESSING BATTLEFIELD DAMAGE Table 2 2 General Assessment Cont DO THE FUEL CELLS APPEAR TO BE 0 K CHECK FOR DAMAGE TO THE SIDE PANELS LEAKS OR FUEL ODOR YES NO GO TO CHPT 12 TS REPAIR DEFERRABLE OR FEASIBLE GIVEN THE MATERIALS TIME AND METHODS AVAILABLE L YES DETERMINE WHETHER THE AIRCRAFT SHOULD BE RECOVERED CANNI BALIZED OR DESTROYED CHECK EACH SYSTEMS OPERATION IS THE POWER PLANT IN WORKING ORDER YES NO IS REPAIR DEFERRABLE OR FEASIBLE GIVEN THE MATERIALS TIME AND METHODS AVAILABLE YES NO DETERMINE WHETHER THE AIRCRAFT SHOULD BE RECOVERED CANNI BALIZED OR DESTROYED CONTINUE NEXT PAGE 55 1520 228 BD ASSESSING BATTLEFIELD DAMAGE Table 2 2 General Assessment Cont DO THE ROTORS APPEAR TO BE IN GO TO GOOD BALANCE CHPT 7 YES NO IS REPAIR DEFERRABLE OR FEASIBLE GIVEN THE MATERIALS TIME AND METHODS AVAILABLE YES NO YES IS THE TRANSMISSION DRIVE TRAIN SYSTEM IN WORKING ORDER NO DETERMINE WHETHER THE AIRCRAFT SHOULD BE RECOVERED CANNI BALIZED OR DESTROYED GO TO CHPT 8 IS REPAIR DEFERRABLE OR FEASIBLE GIVEN THE MATERIALS TIME AND METHODS AVAILABLE YES NO ARE THE HYDRAULIC AND PNEUMATIC SYSTEMS IN WORKING ORDER YES DETERMINE WHETHER THE AIRCRAFT SHOULD BE RECOVERED CANNI BALIZED OR DESTROYED GO TO CHPT 9 IS REPAIR DEFERR
103. F AIRCRAFT ELECTRICAL WIRE REF SHIELDED WIRE FROM BLOWER 19 TO NOISE FILTER DETAIL l Vent and Defog Control 11 Windshield Defog Nozzle 2 Heat Control 12 Plenum Drain 3 Heat Control Cable 13 Plenum Valve Assembly 4 Bleed Air Tube 14 Ventilating and Defogging Blower 5 Mixing Valve 15 Ram Air Intake Gril 6 Plenum 16 Air Distribution Vents Remote Sensor 17 Coupling Fresh Air Inlet 18 Clamp 9 Post Plenum 19 Noise Filter 10 Air Distribution Valves 20 Tube Figure 15 2 Heating and Ventilating System Bleed Air A Model TM 55 1520 22 80 ENVIRONMENTAL CONTROL SYSTEM q 14 SEE DETAIL Vent Control Heat Control Heat Control Bleed Air Tube Mixing Valve Plenum Remote Sensor Fresh Air Inlet I DO OO HD Un C r2 Lr mm Windshield Defog Nozzle Figure 15 3 SHIELDED WIR E FROM BLOWER J TO NOISE FILTER 2 13 Cable 14 15 f 14 Center Post Duct 19 Air Distribution 20 21 MOUNTING BRACKET REF AIRCRAFT ELECTRICAL WIRE REF A Plenum Drain Plenum Valve Assembly Ventilating and Defogging Blower Ram Air Intake Gril Air Distribution Valves Cargo Passenger Area Coupling Cl amp Noise Filter Blower Inlet Tee Valve Duct Heating and Ventilating System Bleed Air C Model TM 55 1520 228 BD ENVIRONMENTAL CONTROL SYSTEM Combustion Heater Plenum Fuel Shut Off Valve Fuel Pump Fuel Pressure Relief Va
104. G The strap must be cut flush with the surface in order to eliminate painful cuts and scratches from protruding strap ends 6 If strap end is not cut flush remove the strap and install a new strap in its place Pick up for appropriate disposal al broken straps and strap ends that were cut off 0 Record BDAR action taken When mssion is complete as soon as practical repair the equi pment system Using standard maintenance procedures BUNDLE TIP LARGE END WITH EYE STRAP Figure 11 23 Self Clinching Cable Strap 11 28 tension setting to 7 TOOL Figure 11 24 Self Clinching Cable Strap and Tool OPTION 2 LI MI TATI ONS Tie Tape 1 Do not use ties on that part wire group or bundle located inside conduit d d 2 When tying wire bundles behind con nectors start ties far enough back from the connector to avoid splaying of con tacts PERSONNEL TI ME e 1 Soldier e Minute Per Tie REQUIRED e Tie Tape item 10 Appx B PROCEDURAL STEPS REQUI RED 1 Tie bundles tightly enough to pre vent slipping but not so tightly that the tape cuts into or deforms the insu lation Be especially careful when tying coaxial cable which has a soft dielectric insulation between the inner and outer conductors 0 Use knot shown in Figure 11 25 3 Tie all wire groups of bundles where supports are more than 12 inches apart Space ties 12 inches or less i WRAP CORD TWICE
105. HE DISCRETION OF THE COMMANDER AUTHORIZED TRAINING FIXES ARE LISTED IN APPENDIX E IN EITHER CASE DAMAGES SHALL BE REPAIRED BY STANDARD PROCEDURES AS SOON AS PRACTICABLE Section GENERAL 1 SCOPE This appendix lists spe and durable supplies not listed in other cial tools and test equipment Several appendices Each kit contains its own special tools are contained in the BDAR inventory list and tool usage instruc kits listed on the next page The kits tions There are no fabricated tools also contain small quantities of parts associated with this BDAR manual Section 11 TOOLS 8 2 SPECIAL TOOL LISTINGS The items levels to accomplish battlefield damage listed in this appendix will enhance assessment and repairs crew members and mechanics at all TM 55 1520 228 BD APPENDIX B SPECIAL OR FABRICATED TOOLS TI NO NSN DESCRIPTION Not Assigned Composite Structures Repair Kit 2 5935 01 161 5883 Connector Repair Kit Special Tools 11851 DMC658 for Electrical Connector Repair 3 4920 01 266 7535 Emergency Repair Kit Special and 11851 DMC895 Common Tools for Electrical Repair including Repair Parts 4 4920 01 266 7534 Fluid Line Repair Kit Special and 78286 Common Tools for Tubing and Hose 10700 20900 041 Repair Including Repair Parts j Not Assigned Fuel Cell Repair Kit 6 Not Assigned High Energy Laser Damage Analysis Test Kit 1 Not Assigned Optical Component Repair Kit 0 Not Assigned Standa
106. HYDRAULIC Figure 9 14 Section 111 AND GASKET SEALS 0 RI NG CATIONS 9 9 APPLI a O rings are used in static and dynamic applications 1 In static applications ring serves as a gasket when it is compressed within a recess Leakage is not normally acceptable 2 In dynamic applications the sealing action is dependent primarily on the resilience of the o rings When moving parts are involved minor seepage may be normal and acceptable A moist surface found on moving parts of a hydraulic unit piston shaft is indication that the seal is being pro perly lubricated the o Union Connection PACKI NGS AND GASKETS 3 Seal replacement is required when a The amount of fluid being lost will cause system failure b The leak creates a hazard c The leak will not permit the system to function safely for one more flight NOTE Packings and gaskets are identi fied by part number on packages Do not remove from package unti ready for use TM 55 1520 228 80 HYDRAULIC b Selection of Proper Packing or Gasket Selection of proper packing or gasket for a particular application is of the utmost importance The exact Size shape and material composition must be properly determined in order for various systems to function correctly Packings gaskets or seals like fit tings are made to an AN MS or NAS standard While gaskets may look alike in general constructi
107. HYDRAULIC HOSE DAMAGE GENERAL INFORMATION The hydraulic hoses on the 58 are braided wire covered rubber hose Repair of damage or wear to the wire braids is deferrable for one more flight provided the rubber inner hose is not leaking under pressure Inspect after every flight If the inner rubber hose is leaking and a replacement assembly is not available manufacture a new hose assembly an elbow fitting is not available make a new hose with a large gentle loop so the hose will not kink MS detachable fit tings from a damaged hose may be reused in the manufacture of a new assembly as long as the threads and the seat are not damaged Swaged fittings cannot be reused OPTION 1 Install New Hose Assembl y BDAR Kit LIMITATIONS None PERSONNEL REQUIRED 9 1 Soldier 20 Minutes MATERI ALS TOOLS REQUIRED e Hydrualic Hose Assembly PROCEDURAL STEPS 1 Remove damaged hose assembly 2 Install new hose assembly BDAR kit t may be necessary to splice two or more hose assemblies together using MS unions to replace the damaged hose assembly No harm will be done if the replacement hose is too long 9 9 TM 55 1520 228 BD HYDRAULIC CUT DAMAGED SECTION Figure 9 10 Damaged Tube Section Complex Bends ORIGINAL TUBE HOSE ASSEMBLY Figure 9 11 Splice Adapter Assembly Installation 55 1520 228 80 HYDRAULIC 3 Record BDAR action taken When 4 Insert the MS sleeve between
108. Has 28 0 V dc Disconnect Before Using TDR TM 55 1520 228 BD APPENDIX F Figure F 7 Radio Receiving Set AN ARN 123 V 1 Sheet 1 of 2 TM 55 1520 228 BD APPENDIX F DRAW NG PART DESI GNATI ON NUMBER FUNCTI ON 1 525041 4 Light Indicator 2 MS27786 23 Switch Toggle Four Pole 3 M39012 16 0004 Connector Plug 4 AS 3188 ARN Antenna Glideslope 5 5955 00 858 6552 Spider Coax Assembly 05211 6 A5 3104 ARN Antenna 1 M39012 16 0004 Connector Plug 0 R 2023 ARN 123 V 1 Receiver 9 M39012 16 0004 Connector Plug 10 M39012 16 0004 Connector Plug 11 M39012 16 0004 Connector Plug 12 M39012 16 0004 Connector Plug 13 640 ARN Antenna Marker Beacon 14 D 1347C ARN Indicator Course NOTE IF 1 D 1347C ARN 82 15 USED WITH THE AN ARN 123 V THE SWITCH ON THE BACK OF THE INDICATOR MUST BE SET TO THE R 1388A ARN 82 POSITION Figure F 7 Radio Receiving Set AN ARN 123 V 1 Sheet 2 of 2 Table F 7 Radio Receiving Set AN ARN 123 V 1 OH 58C ARN123 20A22 0 20A22 3405RE1P11001 20A22 3405RE1P11001 33422 3405RE1P12002 3405RE1P12002 SPLICE SPLICE SPLICE 3405D51P1 3405RE1P1 3405DS1P1 VU 3405DS1P1 3405DS1P1 3405DS1P1 11 51 3405CP1P1 3405CP1P1 3405CP1P1 3405CP1P1 U 40A22 WHT 40422 BLU 40422 ORN 41A20 WHT 41420 BLU 1 Denotes PR S Pair Twisted with Shield TW S Three Wire Twisted with Shield TM 55 1520 228 BD APPENDIX F 5 Figure F
109. Heat Gun item 10 Appx B e 1 3 Hours Per Wire Depending on which Reflector item 10 Appx potting compound is used PROCEDURAL STEPS MATERI ALS TOOLS REQUIRED e Potting Compound Insulation RTV 730 1l Prepare cable for splice Refer to 1 5 8516 synthetic rubber or Figure 11 12 and equivalent Knife PROCEDURAL STEPS 1 Remove damaged insulation and exa mine to insure center conductor is not damaged 2 2 Apply thin coat of potting com pound over the exposed center conductor AM 3 Allow ti me to dry If compound coating does not seem to be sufficient apply additional layers as needed NOTE 4 Record BDAR action taken When mission is complete as soon as Refer to Table 11 5 for X Y and Z practical repair the equi pment system using standard maintenance procedures Figure 11 12 Shielded Cable Repair Preparation 11 17 55 1520 228 80 ELECTRICAL AND AVIONICS SYSTEM INNER SEALING SLEEVE SHIELD SLEEVE Figure 11 13 Shielded Cable Splice Preparation Table 11 5 Shielded Cable Repair 5 Center and shrink the shield over the splice area so that the solder melts and flows Shield sleeve braid must overlap cable braid at both ends Refer tolFigure 11 14 OPTION 2 Sheath Connector and Grounding Sheath 2 Slide the shield sleeve onto one of the cables LIMITATIONS This is a temporary repair until heat shrink is installed 3 Slide the inner sealing sleeve
110. I GNATI ON NUMBER FUNCTI ON CN 998 ASN 43 Gyroscope Displacement 2 1D 1351 A Indicator Heading Bearing 1 CN 405 ASN Compensator Transmitter 4 T 611A ASN Transmitter Induction j M53126E18 325 Connector Plug 6 MS3126E16 265 Connector Plug Figure F 5 Gyromagnetic Compass Set AN ASN 43 and Connecting Cables Sheet 2 of 2 Table 5 Wiring Table Gyromagnetic Compass Set TN1705D22 10422 BLU 1422 GRN 12422 YEL 1322 14422 15422 20422 BLU 1422 GRN 22422 YEL Tp OO r3 c gt gt c c c5 c5 c5 Denotes TWT S Three Wre Twisted with Shield TM 55 1520 229 80 APPENDIX F Figure F 6 Direction Finder Set AN ARN 89 Sheet 1 of 2 F 12 TM 55 1520 228 BD APPENDIX F DRAWI NG PART DESI GNATI ON NUMBER FUNCTI ON l C 7392 ARN 89 Control Radio Set 2 1D 1351 A Indicator Heading Bearing 3 R 1496 ARN 89 Receiver Radio 4 AM 4859 ARN 89 Amplifier Impedance Matching 5 206 032 310 3 Antenna Sense 6 AS 2108 ARN 89 Antenna Loop Figure F 6 Direction Finder Set AN ARN 89 Sheet 2 of 2 SHI ELD SPLICE SHI ELD SPLICE SHI ELD SPLICE P201 P223 P225 P224 P2117 P226 10969 U OH 4 ARN89 6617 SHI ELD SPLICE 6822 SHI ELD D SPLICE 6A22 SHI ELD CG 3492 U COAX C6 3493 Ul COAX CG 3494 Ul COAX CG 3495 Ul COAX CX 10960 Ul SHIELD NOTE Center Conductor of Coax Cable
111. I Joo OO A een fet fin E ES 5 amp ze Stal S 19 17 s E Che oe aolo e Si Gl ol ges FERRE H el amp SaR n 9 HS j5 Tofa 5s IS 8 z ojojo O 1 l d 8 m MES Bici 5 8 5 Sag etmeseeEEEEEEE AR ma 1 cic c s Si ys Sas wo or Ie e ex ox 0 J Oy 451 Qr 42 5 5 g lt Ko R S AIA SIII 4 gt A LOCATE THE MATERIAL BE REPLACED ON THE LINE IN THE LEFT HAND COLUMN B LOCATE THE SUBSTITUTE MATERIAL IN THE VERTICAL COLUMNS 50 SUBSTITUTE STANDARD GAGE FQUAL TO THIS MULTIPLY THE THICKNESS OF THF MATERIAL TO BF REPLACED BY THE FOUND IN STEP A amp B E FACTOR SHOWN AT THE INTERSECTION OF THE LINE AND COLUMN C TO OBTAIN THE MINIMUM THICKNESS OF THE SURSTITUTE MATERIAL THICKNESS OR NEAREST STANDARD NOTE mSteel and aluminum are incom patible materials and normally require special precautions However for BDAR this is an acceptable usage I Refinements to patch repairs such as countersunk chamfered edges anti corrosive treatment and radius corners of the patches are unnecessary fasteners e External patch repairs generally will meet strength criteria for effec tive BDAR Sometimes these repairs must take into consideration the clearan
112. KING NUT 3 TIMES WIDTH OF BUS BAR Figure 11 38 Splicing Bus Bars Figure 11 39 Lengthening Bus Bars 11 39 55 1520 228 BD ELECTRICAL AND AVIONICS SYSTEM LIMITATIONS Some 1055 of battery 5 After removing bad cells prepare voltage 1 25 to 1 50 V dc per cell jumper from 1 foot of No 4 AWG and two removed and amperage capacity terminal lugs Remove 1 2 inch of insu lation from one end of wire and crimp PERSONNEL TIME REQUIRED terminal lug on stripped end of wire Sol dier Measure and cut wire to needed length 30 Mi nutes strip 1 2 inch of insulation and cri mp terminal lug to other end of wire MATERI ALS TOOLS REQUIRED 1 Multimeter with Leads 6 Install jumper across removed cells item 9 Appx 8 in place of terminal links Cells are Rubber Gloves connected in series positive to Protective Goggles negative Figure 11 40 Rubber Apron Torque Wrench Torque terminal screws to between 35 One Foot No 4 AWG Wire or and 50 inch pounds Jf torque wrench is Equivalent not available tighten firmly with wrench or pliers PROCEDURAL STEPS 6 Replace cover and install battery in L Disconnect battery and remove from aircraft aircraft if necessary 2 Release snap fasteners and remove cover 4 Use a multimeter to measure voltage across each cell Normal readings should be 1 25 to 1 5 V dc per cell Remove cells that are dead For engine cranking loads cell voltages as low as 0 6 V dc ar
113. M 4 Heat the adhesive layer 29 temperature set at the tape to shrink it and melt Use reflector 900 F 5 Record BDAR action taken When mission is complete as soon as practical repair the equipment system using standard maintenance procedures ments WIRE Seg Table 11 4 ITEM Wire Repair LOCATION STRIP ELECTRICAL LENGTH WIRING KIT EX Coal 15 16 812 2 BLUE 30 55 14 12 812 3 YELLOW 30 35 OVERLAP ABOUT ONE THIRD WRAP ONLY TIGHT ENOUGH TO HOLD TAPE IN PLACE TAPE WILL SHRINK TIGHTLY WHEN HEATED Figure 11 10 Heat Shrinkable Tape OPTION 2 Insulation Sleeve LIMITATIONS This is a temporary repair PERSONNEL TI ME REQUIRED e 1 Soldier e 10 Minutes MATERI ALS TOOLS REQUIRED e Insulation Sleeving item 10 Appx B Knife e String Nylon Braid or item 10 Appx B Ti e Wraps 11 16 PROCEDURAL STEPS 1 Remove damaged insulation and examine to insure center conductor is not damaged 2 Prepare a transparent sleeve of flexible tubing 1 1 2 times the outside diameter of the wire and 2 inches longer than the damaged portion of the insula tion 3 Split lengthwise and wrap 1 1 2 times around the wire at the damaged section 4 Tie with string or other suitable material at each end and at 1 inch intervals over the entire length Fi qure 5 Record BDAR action taken When mission is complete as soon as practi
114. MAGE LIMITS DEFINITI ON a The allowable damage limits corresponding to the damage measurements of paragraph 4 7 jare designated for a given condition as follows CD Allowable depth of damage C Allowable length width of damage Allowable area of damage D Minimum allowable distance between damages W Allowable largest dimension across web panel damage N Minimum damage factor b Allowable damage limits for pri mary structural elements are associated with the conditions of paragraph 4 9 damage limit for a given condition 5 E measure of the amount of damage that a structural member can sustain and still support the loads associated with the given condition For a given condition all must be equal to or less than the corresponding allowable damage limits and the distance between damages must be damages equal to or greater than the corresponding minimal allowable limit that D lt CD CL lt CL WL lt D D The aircraft may be released for flight in that condition Repair may be deferred although some cleanup and smoothing of the damage will be required as will inspection for damage growth after every flight Special con sideration should be given to damage exposed to the airstream particularly to the effects of ram air rain and petaling Petals may vibrate in the passing airflow rapidly creating cracks in the supporting base metal Large pieces of metal
115. MENTS MATERIALS TOOLS REQUIRED GENERAL INFORMATION The electrical e Substitute Shielded Braid wiring kit has wire replacement segments item 10 Appx B to replace segments up to 9 inches in e Knife length e Center Conductor Splice Item 10 Appx 8 CAUTION e Metal Screw Clamp Sheath Connector or Equivalent Make sure aircraft power is off Disconnect battery before touching PROCEDURAL STEPS any wires 1 Prepare severed ends of cable for LI MI TATI ONS Dependent on splice method application of repair splice and used to connect replacement segment shielding Figure 11 17 step a PERSONNEL TI REQUIRED 2 Select suitable shielding material 1 Soldier and slide over one end of severed cable e 1 Hour 11 21 TM 55 1520 228 BD ELECTRICAL AND AVIONICS SYSTEM PIGTAILS STEP A REN i as INSULATION S umma 5 COVER WITH VINYL SLEEVE AND TIE BOTH ENDS STEP C Figure 11 16 Pigtail Method Repair 11 22 TM 55 1520 228 BD ELECTRICAL AND AVIONICS SYSTEM CENTER CONDUCTOR Red 2 E scd Ro t ET NARA ES STEP A RW f mm v Q m CLAMP SUBSTITUTE SHIELD STEP C Substitute Shielded Braid Repair Figure 11 17 11 23 55 1520 228 BD ELECTRICAL AND AVIONICS SYSTEM MATERI ALS TOOLS REQUIRED Repl
116. Mech os Ammunition Gage Block 1005 06 8226 Ammunition Chute 7 62 6140 00 228 8447 tery Storage NAD 1304 8 Bolt Bolt NAS 1305 8 Bolt Bolt Bolt Bolt Bolt Bolt Drive Motor Feeder Delinker Mau 56 A Igniter Exciter Nut Nut Nut Nut 2 3 4 6 0 10 11 12 13 14 15 16 1 18 19 Nut Pin Quick Release Screws Metal Screws Wood Time Delay Relays TDR s Washer Flat Washer Flat 0 2 TM 55 1520 228 BD APPENDIX D U E H U 9 AT ATA A A NOUN NSN 8 6 PUMP SUBMERGED 2915 01 124 5222 LINEAR ACTUATOR 2995 00 134 4543 FORCE GRADIENT CYL 1680 00 126 4350 PRESSURE ALTI METER 6610 00 179 5254 ATTITUDE INDICATOR 6610 00 150 6583 COURSE INDICATOR 5826 00 505 3094 PRESSURE ALTI METER 6610 00 179 5242 VERTICAL SPEED IND 6610 00 935 4278 VOLTMETER INDICATOR 6625 00 003 8745 PRESSURE ALTIMETER 6610 00 110 3368 VERTICAL SPEED INDICATOR 6610 00 029 6703 TRANSPONDER 5895 00 100 2198 MOUNT 5895 00 063 9498 CONTROL 5895 00 089 4403 MOUN 5895 00 919 9513 ANTENNA 5895 00 935 4975 o a D 3 TM 55 1520 228 80 APPENDIX D Table D 2 Spare and Repair Parts Cont NOUN NSN MOUN 5895 00 935 958 UHF RADIO SET 121 00 138 7990 COMPENSATOR 0005 0 407 4 o c
117. NERAL INFORMATION Nickel um Ni Cad batteries consist of a number of cells connected in series Damage to a cell which does not result in short circuiting and destroying the battery The following procedure gives instruc tions for locating and removing bad Ni Cad battery cells and creating a jumper around the bad cell WARNING Ni Cad batteries use potassium hydroxide a strong caustic alkali as the electrolyte Do not get this electrolyte on your skin or in your eyes Use rubber gloves rubber apron and protective goggles when handling the elec trolyte If accidental contact with the electrolyte is made use ONLY clean water and immediately seconds count flush contami nated areas Continue flushing with large quantities of clean water and get medical attention as soon as possible If steam or spewing electrolyte is observed or the battery is hot to the touch DO NOT ATTEMPT TO remove from the aircraft imme diately CAUTION Penetration of battery case by small arms fire or shrapnel wil cause thermal runaway The battery cells will overheat and rupture melt or explode Exercise extreme caution when repairing the battery TM 55 1520 228 BD ELECTRICAL AND AVIONICS SYSTEM CROSS SECTIONAL AREA OF SPLICE AT LEAST 1 4 X 3 4 IN SCREWS OR BOLTS 1 4 IN DIA FLAT WASHERS REMOVE INSULATION EN ANNSSSNNNNNNSNN CRACKED BUS BAR 2 222222222 FLAT WASHER LOCKWASHER SELF LOC
118. NGER TEST TOLERANCE TOXI C TW ST VI SCOSI TY WARPAGE WEB WHI P GLOS 8 GLOSSARY Cont Chipped or flaked surface caused by the breaking away of the hardened metal and separation of the case from the core The location of a point or direction of movement parallel to the leading or trailing edge of a rotor blade A primary structural element designed to carry weight and resist bending loads in wings and rotor blades Spars typically extend the full length of the wing and taper down to a smaller cross section toward the tip of the wing A longitudinal fore and aft structural element use in semi monocoque design which stiffens the skin Often called a stringer A hole intentionally drilled at the end of a crack or saw cut which normally will prevent further propagation of the crack A longitudinal fore and aft structural element used in Semi monocoque design which stiffens the skin Often called a stiffener As used herein the checking or operation of equipment to determine that the unit functions properly within the limits set forth in this manual The difference between two limiting sizes as a means of specifying the degree of accuracy A poisonous substance The damage of a structural element by turning or torque forces causing permanent deformation The property of a fluid that tends to resist the force trying to make it flow such as gravity or applied pressure The bending or twisting dama
119. OUR FASTENER DIAMETERS FILLER SAME TYPE MATERIAL AND THICKNESS AS EXISTING SKIN OR PATCH EQUAL TO FLANGE WIDTH OF EXISTING A SUBSTRUCTURE EXISTING FASTENERS FORMER FRAME MIN EDGE DISTANCE IS TWO FASTENER DIA 0 5 MIN RADIUS MIN EDGE DISTANCE IS TWO FASTENER DISTANCES REPAIR PATCH es e 444 2722 1 2 or Lu meee FILLER EXISTING SUBSTRUCTURE SECTION A A THRU ASSEMBLED REPAIR REPAIR DOUBLER Figure 4 22 Typical Combination Repair Sheet 1 of 2 TM 55 1520 228 BD RFRAME SKIN PATCH FILLER PATCH DAMAGED SUBSTRUCTURE REPAIR DOUBLER SECTION B B MIN EDGE DISTANCE IS TWO FASTENER DIAMETERS REPAIR DOUBLER ON OPPOSITE SIDE OF HOLE FLANGE LENGTH OF REPAIR DOUBLER TO BE AT LEAST EQUAL TO THE SKIN PATCH LENGTH OR THREE TIMES THE DEPTH OF THE SUBSTRUCTURE CLEANUP OF DAMAGED SUBSTRUCTURE FILLER FORMER FRAME HALF DISTANCE BETWEEN LIGHTNING HOLES WHEN APPLICABLE FASTENER SPACING IS FOUR FASTENER DIAMETERS MAX LENGTH OF DAMAGE ASSUMED EQUAL TO DAMAGE CLEAN OUT WIDTH OF SKIN SKIN PATCH FOUR FASTENER MIN EACH SIDE OF CUTOUT THRU PATCH AND SUBSTRUCTURE EXISTING SKIN view C C THRU ASSEMBLED REPAIR Figure 4 22 Typical Combination Repair Sheet 2 of 2 3 Remove existing rivets where the repair parts will overlap existing rivets If the area is accessible for back drilling holes If not
120. RH Homi ng RL Liaison RM Marker beacon RN Navi gati on RP Special systems RS SHF command RT Radio teletype RU UHF command RV VHF command RX Recorder RZ Interphone headphone 55 1520 22 80 ELECTRICAL AND AVIONICS SYSTEM Table 11 2 Function and Designation Letters Cont CIRCUIT DESI GNATI ON LETTER CI RCUI TS 5 RADAR SA Altimeter SF Intercept SG Gunl ayi ng SM Mapping SN Navi gati on 50 Bombi ng SR Recorder SS Search SV Special systems SW Warning SX Recognition IFF T SPECIAL ELECTRONIC TA Adapter TB Radar control TC Radio control TD Airborne announcing TE Electronic countermeasure TF Repeat back TG GM homi TH Infrared TK Tel emetering TL Attitude indicator TM Chaff dispenser TN Navi gati on TP Beacon crash and locator TQ Transmitters and receivers TR Recei vers TT Transmitters TU Reconnaissance TW Weather devices TZ Bombing devices CI RCUI T DESI GNATI ON LETTER U CI RCUI TS MISCELLANEOUS ELECTRONIC Electronic wiring for which no R S or T designation has been assigned by the procuring activity shall have the circuit function letter U assigned Examples of wiring for which the circuit function letter U will be assigned are common leads to electronic equipments and Systems interconnection wiring Such as antenna or power circuits common to more than one equi pment or system DC POWER and DC control cables for AC systems shall be identi
121. RICAL AND AVIONICS SYSTEM 4 Shrink sealing sleeve over crimp OPTION 3 Split Bolt Splice Connectors with heat gun Use reflector tem perature set at 900 F LIMITATIONS Only to be used on wire sizes AWG No 4 through No 10 Inspect 5 Record BDAR action taken When after every flight mission is complete as soon as practical repair the equipment system PERSONNEL TIME REQUIRED using standard maintenance procedures e 1 Soldier 10 Minutes OPTION 2 Terminal Lug Splicing MATERI ALS TOOLS REQUIRED LIMITATIONS Only to be used on wire e Strippers or Knife item 10 Appx sizes AWG No 10 and smaller This is a e Heat Shrinkable Tubing temporary repair item 10 Appx B e Split Bolt Splice Connector PERSONNEL TI ME REQUIRED item 10 Appx 1 Soldier Heat Shrinkable Tape item 10 Appx 15 Minues Per Splice Reflector item 3 MATERI 15 TOOLS REQUIRED PROCEDURAL STEPS e Terminal Lug Barrel e insulating Sleeve and Tie Wraps or 1 Slide a 3 inch length of large Heat Shrinkable Insulation diameter heat shrinkable tubing over e Crimp Tool one of the wires to be spliced PROCEDURAL STEPS 2 Strip wires and insert into the con nector from opposite sides 1 Select terminal with a barrel large enough to accommodate both wires NOTE 2 Cut off terminal lug tongue Conductors may be folded back one or more times to fill the connec 3 Prepare wire ends tor opening and provide firm
122. S Measuring Skin Panel Damage Se ee Figure 4 6 TM 55 1520 228 BD AI RFRAME 9999999 99S SSH HN SHH SSH HUH SHgu ggsgs Measuring Damage in Webs and Panels 55 1520 228 80 Al RFRAME 2 Honeycomb Sandwich Structures Refer tol Figure 4 7 for the measurement of WL and D If a projectile hits a sandwich panel at an angle the damages in the two skins may be off set and of different sizes Measure the damage on the side with the largest damage usually the exit side and make Sure that the measurement includes the damaged area on the other side WL is the largest dimension across the damage both sides regardless of direction and must include all radiated cracks D is the distance between damages Take and record the measurements as described in paragraph 4 7 8 2 Fittings Splices Attachments and See paragraph 4 12 2 Record all damage on DA Form 2404 d Damage measurements apply after cleanup and smoothing or after BDAR has been accomplished However as a prac tical matter measurements must be taken before smoothing to make a decision on deferrability Hence when estimating damage limits before cleanup and smooth ing make allowance for the material that will be removed in smoothing This applies particularly to cracks The length of the crack must be included in in the depth CD and length CL measurements 4 8 ALLOWABLE DA
123. SHALL BE REPAIRED BY STANDARD PROCEDURES AS SOON AS PRACTICABLE Section INTRODUCTION 6 1 DESCRIPTION POWER PLANT The pu 6 refers to BDAR repair proce 0 power plant consists of a T63 A 700 on ures which have been developed the 58 and a 63 720 on the 0H 58C mounted F5120 0 and 5206 0 6 3 REPAIR PROCEDURE INDEX Engine connections are or fuel oil electrical PARA instrument and engi ne control systems sections of the engine are the Air Bleed Valve Inoperative 6 5 air inlet compressor combuster tur Double Check Valve bine and power and accessory gearbox Inoperative aol BDAR repairs discussed in this 011 Tank Punctured chapter are applicable to both engine Oil Lines Ri gi d Type models Repair 0s s s 9 T Fuel Oil Pneumatic 6 2 ASSESSMENT PROCEDURES Combat line Repair sss damage to the engine usually 1 engine replacement The logic diagram Section COMPONENT EXPEDIENT FIXES 6 4 GENERAL This section has various 6 5 AIR BLEED VALVE 1 VE expedient fixes which can restore the helicopter s mobility in the event of GENERAL INFORMATION During engine engine failure Engine malfunctions start up or part speed operation the can be detected from the following compressor is susceptible to surge due observations to high pressure build up in the rear stages An air bleed valve is employed Abnor
124. TE MAINTENANCE BATTLEFIELD DAMAGE ASSESSMENT AND REPAIR FOR HELICOPTER OBSERVATION OH 58A amp OH 58C DISTRIBUTION STATEMENT A Approved for public release distribution is unlimited TM 55 1520 228 BD dated 4 January 1991 is changed as follows 1 Remove and insert pages as indicated below New or changed text material is indicated by a vertical bar in the margin An illustration change is indicated by a miniature pointing hand Remove Pages Insert Pages Ds blank i and ii 1 5 1 6 1 5 and 1 6 2 Retain this sheet in front of manual for reference purposes By Order of the Secretary of the Army PETER J SCHOOMAKER General United States Army Official Chief of Staff SANDRA R RILEY Administrative Assistant to the Secretary of the Army 0518801 DISTRIBUTION To be distributed in accordance with Initial Distribution Number IDN 311704 requirements for TM 55 1520 228 BD 55 1520 228 BD LIST EFFECTIVE PAGES Insert latest changed pages Dispose of superseded pages in accordance with regulations NOTE On a changed page the portion of the text affected by the latest change is indicated by a vertical line or other change symbol in the outer margin of the page Changes to illustrations are indicated by miniature pointing hands Changes to wiring diagrams are indicated by shaded areas Dates of issue for original and changed pages are Original 4 January 1991 Change
125. THE COMMANDER AUTHORIZED TRAINING FIXES ARE LISTED IN APPENDIX E IN EITHER CASE DAMAGES SHALL BE REPAIRED BY STANDARD PROCEDURES AS SOON AS PRACTICABLE Section INTRODUCTION 14 1 SCOPE 14 2 ASSESSMENT PROCEDURES Visually inspect the damaged de icing components 8 The de icing system is the means to determine the extent of damage and by which the engine is kept from an the repair required icing condition The system consists of a de ice switch and a de ice control 14 3 REPAIR PROCEDURE INDEX actuator protected by a 5 amp circuit breaker Refer to figure IEL PARA b This chapter consists of two BDAR De lce Valve or Control fixes which can be applied for repair of c oe 114 4 the de icing system components Section DE ICE VALVE OR CONTROL 14 4 GENERAL INFORMATION Damage to 2 Record BDAR action taken When control rod may be repaired by using one mission is complete as soon as of the following repair options practical repair the equi pment system Using standard maintenance procedures OPTION 1 Splice Repair OPTION 2 Control of Valve PERSONNEL TIME REQUIRED LIMITATIONS None PERSONNEL REQUIRED e 1 Soldier 1 Soldier e 1 Hour Hours MATENI rn REQUI RED MATERI ALS TOOLS REQUIRED 0 041 or 0 032 Safety Wire Flat or Round Piece of Materia Example engine cowl hold open rod PROCEDURAL STEPS e Drill with Bit e No 8 screws or b
126. TUTE MATERI ALS PARTS BDAR FIXES SHALL BE USED ONLY IN COMBAT OR FOR TRAINING AT THE DISCRETION OF THE COMMANDER AUTHORIZED TRAINING FIXES ARE LISTED IN APPENDIX E EITHER CASE DAMAGES SHALL BE REPAIRED BY STANDARD PROCEDURES AS SOON AS PRACTICABLE Section 1 0 1 SCOPE This appendix contains lists and tables of substitute materials and parts which can be used on the 0 58 aircraft for BDAR fixes GENERAL The lists and tables for resi made up of the following Essential spare parts Table D 1 b Spare and repair parts Table D 2 thru D 3 c Fuels Table D 4 thru D 7 d Lubricants and hydraulic fluids Table D 8 e This appendix contains genera information concerning types uses and effects of POL substitutes and methods of purging and flushing systems f Some products are made up of che mical ingredients which are not com patible with products used on an QH 58 aircraft Some fuels oils and hydraulic fluids can have an adverse effect on systems and components with the 0H 58 systems therefore it is advisable to properly identify the product by specification number and name from cross reference with primary and expedient products available National stock numbers are used in conjunction with specification numbers to distinguish them from foreign pro ducts The identification of NATO product numbers relate directly to U S Military Specification numbers and thus ar
127. When BULLET DAMAGE LIMITATIONS Small oil loss can be tolerated If aircraft is run for an extended period of time with little or no oil gearbox will jam PERSONNEL TIME REQUIRED Sol di er 15 Mi nutes MATERI ALS TOOLS REQUIRED Solvent Cleaner item 7 Appx Rubber Sheet Tape Army Green item 50 Appx or Equivalent Sealant item 4 Appx C PROCEDURAL STEPS 1 Clean damaged area with solvent if available Place a rubber sheet 1 2 inch to 3 4 inch larger than hole under green tape Alternatively if rubber Sheet not available place sealant under tape 2 Close bullet hole with green Army tape 3 Inspect after every flight 4 Record BDAR action taken mission is complete as soon as practical repair the equi pment system Using standard maintenance procedures When TM 55 1520 228 BD CHAPTER 9 HYDRAULIC BDAR FIXES SHALL BE USED ONLY IN COMBAT OR FOR TRAINING AT THE DISCRETION OF THE COMMANDER AUTHORIZED TRAINING FIXES ARE LISTED IN APPENDIX E IN EITHER CASE DAMAGES SHALL BE REPAIRED BY STANDARD PROCEDURES AS SOON AS PRACTICABLE Section INTRODUCTION 9 1 SCOPE The QH 58 hydraulic system lines The location of a leak can only operates at pressures of 575 to 625 psi be determined by visual examination This pressure is produced by the Refer to lable assessment logic hydraulic pump 9 The of the hydraulic system hydraulic fluid is routed to the flight
128. YSTEM FOLD PARALLEL TO WIRE COVER WITH INSULATING TAPE Figure 11 4 8 Cover tape splice area with electrical 9 If a section of replaced a double Figure 11 5 10 Record BDAR action mission is complete as soon as practical repair the equipment system using standard maintenance procedures to be can be made wire needs repair taken When OPTION 5 Casing Splice Method LIMITATIONS This is an emergency repair for one time flight only type PERSONNEL TI ME e 1 Soldier e 10 Minutes REQUI RED Twist Wire Repair MATERI ALS TOOLS REQUIRED Cylindrical metal casing such as bal point pen refills expended cartridges etc Insulation Sleeve or Tape item 10 Appx B Crimp Tool hammer pliers etc Wire item 10 Appx 8 PROCEDURAL STEPS 1 Fabricate splices approximately 1 to 2 inches long from small metal casing NOTE Ball point refills or expended cartridge shell casings when cut to length make excellent spli ces Figure 11 6 2 Strip 1 2 to 1 inch insulation from both ends of wire to be spliced 3 Insert wires into casing splice and crimp tightly with pliers or a hammer and small iron bar 1 11 TM 55 1520 22 80 ELECTRICAL AND AVIONICS SYSTEM TWO THREE OR FOUR PIGTAILS FOLD PARALLEL TO WIRE COVER WITH INSULATING TAPE REPLACEMENT SECTION Figure 11 5 Replacement Section Twist Wire Repair BALL POINT PEN REFILL CUT CUT
129. acement Segment item 10 Appx BJ Stripper or Knife e Splice item 10 Appx e Insulation Sleeve item 10 Appx BJ Crimp Too PROCEDURAL STEPS 1 Cut out damaged cable up to 9 inches in length 2 Prepare cable for splice Refer to Figure TI T7 and 3 Use one of the options of paragraph 11 5 to splice the ends of the replace ment segment onto the damaged cable 4 Record BDAR action taken When mission is complete as soon as practical repair the equipment system using standard maintenance procedures 11 10 SHIELD TERMINATORS GENERAL INFORMATION The kit contains various types of shield terminators for shielded cable LI MI TATIONS repair This is a temporary PERSONNEL TI ME 1 Soldier e 15 Minutes REQUI RED MATERI 15 TOOLS REQUIRED Shield Terminator item 10 Appx Reflector Heat Gun Heat Source Stripper or Knife Insulating Sleeve item 10 Appx PROCEDURAL STEPS 1 Prepare cable for repair Refer to Figure 11 18 11 24 25 30 WINDOW STRIP 25 30 A END STRIP 25 30 END STRIP BRAID FOLDED BACK Figure 11 18 Shield Terminator Repair Preparation 2 Position shield terminator on cable as shown in figure 11 19 Select the smallest terminator that slides easily over the prepared cable 3 Heat shield terminator until solder melts and flows into wire strands red color disappears and seals melt and flow at both ends Use reflecto
130. acement segment onto damaged wire using one of the options in paragraph 11 9 4 Record BDAR action taken When mission is complete as soon as practical repair the equipment system using standard maintenance procedures TM 55 1520 228 BD ELECTRICAL AND AVIONICS SYSTEM 11 7 DAMAGED WIRE INSULATI ON GENERAL INFORMATION If the wire insu lation is damaged but the wire itself is not repair of the insulation may be accomplished by installing heat shrink able tape a transparent sleeve of flexible tubing and securing with nylon braid or some other means CAUTION Make sure aircraft power is off Disconnect battery before touching wires OPTION 1 Heat Shrinkable Repair Tape LIMITATIONS This is a temporary repair PERSONNEL REQUIRED e 1 Soldier e 10 Minutes MATERI ALS TOOLS REQUIRED e Heat Shrinkable Tape item 10 Appx B e Reflector item 10 Appx Heat Gun Heat Source item 10 Appx PROCEDURAL STEPS l Start wrapping tape at one end of area to be covered 2 Overlap each turn about one third of tape width Overlap of more than 50 per cent or multiple wraps are not recom mended Excess thickness prevents heat transfer to the inner layer Refer to Figure 11 10 3 Apply heat to end of last lap to soften the meltable adhesive and press it into position while warm Use reflector 5 temperature set at 900 F 11 15 TM 55 1520 228 BD ELECTRICAL AND AVIONICS SYSTE
131. acking where 4 Install plug and packing where 17 7 was previously switch 8 was previously installed installed 5 Secure loose electrical connector 5 Secure loose electrical connector and cable with tie wraps and cable with tie wraps 6 Check for leaks 6 Check for leaks 1 Record BDAR action taken When 7 Record BDAR action taken When mission is complete as soon as mission is complete 85 soon as practical repair the equipment system practical repair the equipment system using standard maintenance procedures using standard maintenance procedures 8 9 011 HOSES AND LINES LEAK OR 8 8 LOW PRESSURE SENSING SWITCH C RESTRICTION CRIMP LEAK GENERAL Lane Damaged a hoses GENERAL INFORMATION If oil is being and lines 6 of lost due to damage at low pressure transmission it ety ma y i sensing switch 8 the by manufacturing a new hose or line or Switch can be ate and replaced with by installing a replacement section for a threaded plug provided the the damaged section Similar repairs transmission oil pressure gauge is are outlined ROLE ll operable and reliable and may be FIDCM for the transmission 011 system LIMITATIONS OIL PRESS warning light would be inoperable Only the 8 10 TRANSMISSION BULLET DAMAGE transmission oil pressure gauge would monitor transmission oil pressure GENERAL INFORMATION If the trans mission is hit by a bullet which exits PERSONNEL R
132. adio be sure that FM 1 circuit breaker and BAT on the overhead console are off Slide the No 1 FM radio into the mounting panel and turn the six faste ners one quarter turn clockwise to secure the unit 9 Connect of the No the coax cables to the rear 1 FM radio 10 Attach vent screen to left side of horizontal console NOTE The above procedures apply to the No 1 FM radio and to the No FM radio when it is installed except that J3 and J4 are not Used on the second radio OPTION 2 Antenna LIMITATIONS Some loss of antenna gain and radio transmitter power Construction of Replacement PERSONNEL TI ME REQUIRED 1 Soldier 1 Hour REQUI RED Cable Coax RG 58U or Other Available Coax Tape Electrical item 46 Appx C or Equivalent Resistor Carbon 1 Watt 52 9 5 percent PROCEDURAL STEPS L Determine length of wire needed for the radiating element by using Figure 11 45 Example 11 45 TM 55 1520 228 BD ELECTRICAL AND AVIONICS SYSTEM Frequency Wavelength Wm 8 so 6 59 5 89 MHz 100 3 2 200 1 400 50 soo 00 800 d 1 20 2 3 10 cm 4 L 5 L 4 10 3 2 20 30 1 m os 30 0 6 a 0 5 Figure 11 45 Frequency vs Wave Length TO CHANGE MULTIPLY BY Centimeters Inches 0 394 Meters Feet 3 280 11 46 radio with frequency range of 30 to 69 95 MHZ Center of frequency range is 50 MHZ
133. aft or component part using damage assessment markings as shown in d Status Symbols Status symbols used in aircraft logbooks to record defects are defined below 1 Red X red X shows that a defect exists and the aircraft is unsafe for flight TM 55 1520 228 BD GENERAL INFORMATION outside authorized standard repairs and may degrade the inherent safety of the helicopter Therefore BDAR actions are not intended to supplement replace stan dard maintenance practices during peace time nor should they b mployed indis criminately to facilitate training b Repairs described in this manual which can be appropriately accomplished in order to provide training are listed in Appendix and are highlighted in each repair chapters repair procedure index The trainable repair in the index will be blocked in TASKS AND RESPONSIBILITIES 2 Circled red X A red X inside a red circle indicates a limiting defect aircraft may be flown under specific limits as directed by higher authority or as directed locally until corrective action is taken 3 Red horizontal dash a This symbol indicates an inspection special inspection com ponent replacement maintenance opera tional check or test flight is needed The symbol is also used to indicate that a normal modification work order MWO is overdue b This symbol also shows that the condition of the equipment is unknown A potent
134. and leaks Where feasible plastic and rubber parts should be inspected for swelling deformation and other damage b Record BDAR action mission is complete as soon as practical repair the equipment system using standard maintenance procedures taken When Table 9 2 Seals Reference and Temperature Guides Chart MI LI TARY PARKER BASE TEMP GUI DE DURO SPECIFICATION COMPOUND POLYMER CONT SERV METER SERVICE Air Force and Navy AN6227B MI L P NITRILE MI L H 5606 AN67230B Class PS 01 30 5 BUNA N 65 F to 180 F 10 MI L H 83282 TRILE 529513 NITRILE aircraft fuel Synthetic NAS617 Comp Type 1 47 071 BUNA 65 F to 250 F 10 1 1 7808 AN6290 Hydrualic 011 2 3 MI L P 5510 N507 9 BUNA N 65 F to 180 F MI L H 83282 NAS1593 MI L R 25897 1070 1 High temperature NAS1594 MI L R 25897 High temperature Elastomer 20 F to 400 F fluid resistant rr spur ser comouno ron com sev SERI ES ASTMI D735 58T COMPOUND POLYMER CONT SERV METER SPECI FI CATI ONS Freon 12 weather amp salt water 2 3 5 17208 1 F2 C147 7 65 F to 300 F 70 resistant AMS3209 General purpose industrial 2 3 SC712BE1 F2 C526 7 65 F to 300 F 70 Neoprene AMS3209 Skydrol Cellulube amp other phosphate esters steam ETHYLENE water air dilute 2 3 R810 B F2 PROPYLENE 65 F to 300 F 80 acids amp alkalis gt
135. are employed in routine repairs to the helicopter 3 Chapter 3 is not used in this manual It would normally contain repairs for equipment which does not fall under one of the standard helicopter functional groups 4 Each functional group chapter is organized as follows Section Introduction 1 Scope Purpose of the chapter 2 Assessment procedures General assessment information for the repairs Covered therein 3 Repair procedure index b Section Repair Item subsection is included for each repair item covered in that functional group It contains the following 1 General About the nature and cause of damage and repair 2 Item and trouble statement with a Limits given b Personnel and time required to effect repairs c Materials and tools needed d Procedural steps to accomplish the repair 3 If more than one method of repair can be used the various options will be included next NOTE The first option is the preferred choice the second option is the next preferred etc Selection of the option should be the most preferred method possible under the circumstances and with the available materials and manpower viii 55 1520 228 BD HOW TO USE THIS MANUAL Cont 5 Finding Repairs in this Manual a When the damage is obvious and known find the functional group chapter of which the damaged item is a part Turn to the repair procedure index section I subparagraph c of each
136. as they do not interfere witn personnel for use with any metal tubing such as or with operating equipment Long lines steel titanium or aluminum alloy and hoses should be clamped to hard sup Place tubing in the cutting tool with ports at convenient intervals not the cutting wheel at the point where exceeding 24 inches the cut is to be made 55 1520 228 BD HYDRAULIC G N N O OQ gt Q N 9 2 Quick Disconnect Pressure Quick Disconnect Return Filter Return Filter Pressure Vent Line Reservoir Tachometer Generator Check Valve Hydraulic Pump Case Drain Hose Solenoid Valve Hose Return Hose Return 14 15 16 17 19 20 21 22 23 24 25 5 Hose Pressure Hose Pressure Hose Return pressure Switch Relief Valve To Servo Actuator Collective To Servo Actuator Cycilc Solenoid Valve Tee Fitting Hose Filter Return Hose Filter Pressure Hose Pump inlet Figure 9 1 Hydraulic System TM 55 1520 228 80 HYDRAULIC PRESSURE return SUCTION 1 Reservoir Filter Bypass Valve 2 Baffle Relief Valve 3 Scupper Drain 10 Solenoid Valve 4 Quick Disconnects 11 Pressure Switch 5 Pump 12 Servo Actuator Cyclic 6 Check Valve 13 Servo Actuator 7 Filter Collective Figure 9 2 Hydraulic System Schematic TM 55 1520 228 BD
137. cal repair the equi pment system using standard maintenance procedures INSULATING SLEEVING SPLIT LENGTHWISE AND TIED IN PLACE WITH NYLON BRAID Figure 11 11 Insulation with Sleeving Repair OPTION 3 Tape Insulation LI MI TATI ONS repair This is a temporary PERSONNEL TI ME e 1 Soldier e 5 Minutes Per Wire REQUI RED MATERI 15 0015 REQUIRED e Tape Electrical item 49 Appx Knife TM 55 1520 228 80 ELECTRICAL AND AVIONICS SYSTEM PROCEDURAL STEPS 11 8 SHIELDED CABLE REPAIR 1 Remove damaged insulation and GENERAL INFORMATION The following pro examine to insure center conductor is cedures may be used to repair severed not damaged Shielded cables 2 Wrap tape over exposed center con OPTION 1 Shielded Cable Splice ductor of wire Tape should extend 2 inches over the wire insulation at each LI MI TATIONS Repair is good for cables end of the area to be covered rated at 125 C or above 3 Record BDAR action taken When PERSONNEL TIME REQUIRED mission is completed or as soon as e 1 Soldier feasible repair using standard main 15 Minutes tenance procedures MATERI ALS TOOLS REQUIRED OPTION 4 Potting Compound Insulation e Appropriate Size Splice item 10 8 LIMITATIONS This a temporary Appropriate Size Sealing Sleeve repair item 10 e Crimping Tool item 10 Appx B PERSONNEL TIME REQUIRED Strippers item 10 Appx BJ e 1 Soldier e
138. ce AVIM support teams b Standard repair techniques for the 58 helicopter are included in other technical manuals which are referenced in Appendix A f this TM Details of these procedures are not duplicated in whole in this TM If the repairs are more than one page in length the repairs may only be referenced in appropriate chapter c All possible types of combat damage and failure modes cannot be pre dicted nor are all effective field expedient repairs known This TM pro vides guidelines for assessing and repairing battlefield failures of 58 helicopters and is not intended to INTRODUCTION be a complete catalog of all possible emergency repairs The repairs described here will serve as guidelines and will stimulate th xperienced mechanic operator to devise repairs as needed to rapidly return equipment to operation in a combat situation d The direct replacement of a piece of equipment by its spare even under battlefield conditions is not a BDAR fix and may not be covered is in this TM standard procedure should be per formed in preference to a BDAR fix when time and spares are available 1 3 APPLICATION a The procedures in this manual are designed for battlefield environments and should be used in situations where standard maintenance procedures ar impractical These procedures are not meant to replace standard maintenance practices but rather to supplement them stric
139. ce of moving parts e g control surfaces doors etc In low stress areas patches may only be necessary to provi de aerodynamic shape to prevent ram air effect or to keep water out Damage in these areas can be covered with thin gauge metal or Army green tape In some areas negligible damage can be ignored Use environmental protection for exter nal repairs if possible Where an access hole is large or can be made larger for internal repair an internal or external repair may be used External repairs should be aligned within 15 either side of the direction of air flow f General Repair Requirements Restore structural continuity by restoring original structure or by bridging the damage Original strength should be restored if possible Weight and appearance are unimportant in battle damage repair Structural stiffness should be sufficient to assure loads are properly distributed and to avoid serious vibrations Use shims to avoid joggles Avoid hand formed and fitted parts Where a stringer stiffener is light 1 1 2 X 1 1 2 X 0 060 inches or less and the stringers on either side of the damage or fracture are sound apply a skin patch 2 gauges thicker over the damaged area 55 1520 228 BD AI RFRAME Special Repair Techniques One method to create a complex curve in a normally straight angle or T Profile member is to place appropriate cuts and stop drill holes to allow as given im Figure 1 16 This field expe
140. chapter to locate the item being repaired Then turn to the repair section and review each option to ascertain the appropriate fix Read the entire section for the option then effect the repairs following the procedures given b When the damage is hidden and or unknown follow the overall assessment proce dures provided in chapter 2 and follow the procedures and directions provided 6 Preparation a Each mechanic technician shall have read chapters 1 and 2 and become familiar with the repairs and layout of the manual prior to attempting to accomplish BDAR repairs b All warnings cautions and safety precautions shall be followed inasmuch as possible at all times during BDAR procedures so as not to further damage and or jeopardize either personnel or the equipment during or subsequent to the BDAR action Ensure all documentation is completed as directed in this manual and by local command 7 Expendable Durable Supplies and Materials a Each fix or repair option contains a short listing of materials and tools con sidered basic to the repair It is important to note that th xpendable materials listed usually cover a wide range for any one item Example MATERIALS TOOLS REQUIRED eDrill with Bit eSheet Metal items 131 142 Appx eRivets items 98 115 Appx In this example sheet metal covers the range of items 131 thru 142 ir Appendix C This means that depending on the circumstances and location
141. clamping 4 Slip an insulating sleeve 1 inch eStrip wires 1 2 inch if folding longer than terminal lug barrel over the back is not required end of one of the wires and insert wire eStrip wires 1 1 4 inch if single end into the barrel as shown in Figure folding back is required 11 3 eStrip wires 2 1 2 inch if double folding back is required 5 Crimp barrel in center 3 Tighten nut securely 6 Slide insulating sleeve over the terminal lug barrel splice and secure 4 Wrap the splice with heat shrinkable in place by using tie wraps or heating tape Cover all metal parts and overlap if heat shrink sleeve is used onto insulation 1 Record BDAR action taken When 5 Heat the end of the tape to soften mission is complete as soon as the adhesive layer and press it into practical repair the equipment system position while warm Use reflector using standard maintenance procedures located in A5 of wiring kit tem perature set at 900 F TM 55 ELECTR S 6 Heat splice Use reflector kit 1 Center over 8 Heat the spl perature mi ddl e may not insulation 9 Record BDAR action mission is complete practical using OPTI ON LI MI TATI ONS repair E gt 1520 228 BD ICAL AND AVIONICS SYSTEM BARREL DIAMETER LARGE ENOUGH TO ACCEPT BOTH WIRES TEP A SS CUT OFF TONGUE FLUSH WITH PRE INSULATION INSULATING SLEEVE ONE INCH LONGER THAN TERMINAL LUG BARREL 2
142. create any of the above conditions Section EXPEDIENT STRUCTURAL REPAIRS 4 15 GENERAL Fasteners BDAR can be carried mM out using any form of fastening device Many of these expedient repairs which is available at the time e g will restore the airframe to condition nuts bolts rivets etc as long as 1 Inspection for damage growth will strength requirements are met Use generally be required after every accepted practices regarding fastener flight and damage should be repaired edge distance and spacing The faste as soon as practical by standard main ners used in a single repair should be tenance procedures of the same type b Multiple Damage Special atten d Metal Selection All repair tion should be given to structural com patches should be manufactured from ponents which have sustained damage in material of the same or similar specifi multiple locations It is essential cation as the damaged area but at least that damage to an individual structural one gauge or 10 percent thicker When item not be considered by itself Suit required repair materials are una able repair will often depend on the vailable substitutions can often be condition of the adjacent structure In made to produce a desired strength some cases undamaged adjacent structure Table 4 8 kross lists various types of may satisfactorily take the load of the metal and instructions on how to substi damaged item Since time is an over tute one type of
143. ction refer to repair procedures or a replacement NTRODUCTI ON fuel system must be evaluated very care fully to determine damage which requires immediate repair and that which does not constitute a flight hazard 12 2 ASSESSMENT PROCEDURES Refer to Table 12 1 12 3 REPAIR PROCEDURE INDEX PARA Hose and Line Replacement 9 71 0 Ring Damage Fuel Substitution 12 6 Fuel Cell Repair 1221 LINES AND HOSES hose may be manufactured if a long enough hose section and MS fittings are available refer to repair procedures d Never are reusable reusable 12 5 O RING DAMAGE Refer to paragraph 9 10 The same criteria that applies to hydraulic o rings also applies to o rings in the fuel system 12 6 FUEL SUBSTITUTIONS If the standard fuel is not avail able a substitute fuel must be used Check Mppendix D a compatible fuel b Record BDAR action taken When mission is complete as soon as practical repair the equi pment system using standard maintenance procedures 12 1 discard MS fittings they The MS21922 sleeve is not TM 55 1520 228 BD FUEL SYSTEMS CAP AND ADAPTER SEE DETAIL A RECEI VER NOTE RECEIVER REPLACES CAP AND ADAPTER ON HELICOPTERS EQUIPPED WITH CLOSED CIRCUIT REFUELING PROVISIONS Figure 12 1 OH 58 Fuel System com cn on Fw nr Lr Cover Assembly Low Level Switch Lower Transmitter Fuel Pump Fuel Shut Off Valve
144. cu feet Approximate Conversion Factors To change To inches centimeters feet meters yards meters miles kilometers square inches square centimeters square feet square meters square yards square miles acres square meters square kilometers square hectometers cubic feet cubic meters cubic yards cubic meters fluid ounces milliliters pints liters quarts liters gallons liters ounces grams pounds kilograms short tons metric tons pound feet newton meters pound inches newton meters F Fahrenheit temperature Multiply by 2 540 305 914 1 609 6 451 093 836 2 590 405 028 765 29 573 473 946 3 785 28 349 454 07 1 356 11296 Multiply by ounce inches newton meters 007062 centimeters inches 394 meters feet 3 280 meters yards 1 094 kilometers miles 621 square centimeters square inches 155 Square meters square feet 10 764 square meters square yards 1 196 square kilometers square miles 386 square hectometers acres 2 471 cubic meters cubic feet 35315 cubic meters cubic yards 1 308 milliliters fluid ounces 034 liters pints 2 113 liters quarts 1 057 liters gallons 264 grams ounces 035 kilograms pounds 2 205 metric tons short tons 1 102 Temperature Exact 5 9 after subtracting 32 Celsius temperature 066635 000 This fine document Was brought to you by me Liberated Manuals free army and government manuals Why do I do i
145. d crack with solvent to remove the oi 2 Seal crack with tape 3 Replenish oil supply 4 Record BDAR action taken When mission is complete as soon as practical repair the equi pment system Using standard maintenance procedures OPTI ON 3 PERSONNEL TIME REQUIRED Sealant for small holes 1 Soldier 1 Hour MATERI ALS TOOLS REQUIRED Solvent Naptha item 7 Appx C or Equivalent Sealant Silicon item 4 Appx or Equivalent Wood Plug PROCEDURAL STEPS 1 Clean area around hole with solvent to remove all traces of oil so sealant will stick 2 Fill hole and surrounding area with sealant I b is large enough use wood plug as a anl filling hole with seal ant 4 After sealant has dried replenish oil supply 5 Record BDAR action taken When mission is complete as soon as practical repair the equipment system using standard maintenance procedures OIL TANK WALL WOOD PLUG OPTIONAL n SEALANT Figure 6 5 Sealant for Small Holes OPTION 4 for smal Screw holes PERSONNEL ME 1 Soldier 30 Mi nutes Washer and Gasket REQUI RED MATERIALS TOOLS REQUIRED Screw Sheet Meta Gasket Material item 20 Appx Washer PROCEDURAL STEPS l Cut a piece of gasket material that will overlap the hole by about 1 inch from the center of the hole 2 Pierce a small hole in the center of the gasket material 3 Using the sheet metal screw
146. d the transmission supporting structure shows no damage release for flight Watch for any unusual vibra tions in flight Inspect after every flight until structure and alighting gear can be replaced e If alighting gear or its sup porting structure is not functional or the transmission or its supporting structure show any sign of damage aircraft will be grounded until problem is corrected This will most likely go beyond scope of BDAR SKID DAMAGE Plate should extend one foot on each side of damaged area Locate center of plate at center of skid tube E u 5 3 If there no impediments the new plate may be installed over the old shoes otherwise remove shoes Instal plate using 1 4 inch cherry rivets or steel clamps Figure 5 4 Clamps may be fabricated if not available Figure 5 5 NOTE The aft end of the skid tube is bent up and a steel plate cannot be formed to follow this contour Do not extend steel plate beyond Start of curvature 2 Record BDAR action taken When mssion is complete as soon as practical repair the equi pment system using standard maintenance procedures TM 55 1520 228 BD ALIGHTING GEAR Figure 5 4 Clamp Repair TM 55 1520 228 BD ALIGHTING GEAR Figure 5 5 Fabricated Clamp TM 55 1520 22 80 CHAPTER 6 POWER PLANT BDAR FIXES SHALL BE USED ONLY IN AT THE DISCRETION OF THE COMMANDER AUTHORIZED TRAINING FIXES ARE LISTED IN APPENDIX E IN EITHER CASE DAMAGES
147. d with no degrada tion of any system operating charac teristics No periodic inspection or replacement is required with a permanent repair 2 A temporary repair returns the electrical wiring systemto a reduced level of capacity with a possible slight reduction of system operational capabi lity Temporary repairs must be reinspected at 100 flight hours At this time a permanent repair will be performed or an extension of use for the temporary repair will be granted NOTE Temporary repairs established in the TM will only be applied in time of war The commander or his designated representa tives may authorize deviations necessary to accomplish wartime requirements d Repair Techni ques 1 n battle arise that will situations may require the assessor and repair personnel to develop innovative repair techniques This section des cribes and illustrates some repair capa bilities to broken and or damaged wires shielded or coaxial cables electrical connectors and associated electrical components in the combat environment 2 Prior to performing any of the listed repairs the repair technician must be knowledgeable in the application of the basic repair procedures and pro ficient in the use of wiring repair tools and materials 11 5 SPLICING UNSHIELDED WIRES GENERAL INFORMATION This procedure provides for repairing damaged unshielded wires WARNING Do not be misled by the term low voltage Pot
148. e Aircraft Driveshaft Coupling Jet Engine Lubricating Grade 1010 98308 ISSUE TM 55 1520 228 BD APPENDIX C APPENDIX C Section 11 EXPENDABLE SUPPLIES AND MATERIALS LIST Cont ITEM UNIT OF NUMBER NSN DESCRI PTI ON ISSUE 25 9505 00 596 5101 Lockwire Steel 0 020 81348 RO QQ W 423 26 9505 00 293 4208 Lockwire Steel 0 032 81348 RO QQ W 423 21 9505 00 331 3275 Lockwire Steel 0 041 81348 RO QQ W 423 28 9150 00 186 6681 Lubricating Oil MIL L 2104 QT Grade 30 15958 29 9150 00 180 6266 Oil MIL L 23699 QT 30 9150 00 782 2627 011 MIL L 7808 QT 31 5310 00 297 3751 Nut Assortment 81348 FFN836 PG 32 5330 00 966 8657 Packing Preformed Assortment PG 31808 MAOK311 33 9250 00 250 0926 Petroleum Technical USP CN White VV P 236 34 8010 00 082 2450 Primer Epoxy Polyamide MIL P 23377 KT 35 8030 00 664 4968 Putty Chromate 81349 RO MI L P 8116 36 5320 00 006 4912 Rivet Blind 92215 RV1100 4 3 BX 37 5320 00 117 6826 Rivet Blind 96906 MS2040AD4 4 BX 38 5320 01 033 8179 Rivet Blind 81349 MIL R 7885 6 BX 39 5320 01 839 2146 Rivet Blind 80205 NAS1738M4 3 BX 40 5320 01 937 5448 Rivet Blind 11818 3 16 in BX CR2249 5 5 1 5320 00 721 5211 Solid Aluminum A470 4 6 BX 88044 4 5330 00 060 8212 Sandpaper 600 Grit SH 43 5330 00 244 7201 400 Grit A A 1200 SH 44 5330 00 721 8117 180 Grit A A 1200 SH 45 5350 00 224 7203 320 Grit 1047 SH 46 5350 00
149. e 12 4 Rubber Repair Plug Assembly 3 8 TYPICAL 5 PLACES EQUALLY SPACED Figure 12 5 Plug Modification for Three Plane Repair 12 9 12 10 Blank 55 1520 228 BD CHAPTER 13 FLIGHT CONTROLS BDAR FIXES SHALL BE USED ONLY IN COMBAT OR FOR TRAINING AT THE DISCRETION OF THE COMMANDER AUTHORIZED TRAINING FIXES ARE LISTED IN APPENDIX E IN EITHER CASE DAMAGES SHALL BE REPAIRED BY STANDARD PROCEDURES AS SOON AS PRACTICABLE Section 1 13 1 GENERAL a The flight control system is made NTRODUCTI ON and tail rotor controls to the aft flight control components Refer to Figure 13 1 for a schematic of the up of the main rotor collective controls system cyclic controls and the tail rotor con trols The tail rotor pedals are con 13 2 ASSESSMENT PROCEDURES Refer to nected to the tail rotor assembly Table 13 1 b This chapter contains some BDAR 13 3 REPAIR PROCEDURE NDEX procedures which may be used to accomplish repairs to the flight control PARA tubes Flight control tubes connect the copilot s and pilot s cyclic collective Tubes Flight Control 13 5 Section l TUBES FLIGHT CONTROL 13 4 SUBSYSTEMS AND ASSEMBLIES There the aircraft is on the ground if are various subsystems and assemblies within the flight control system that are vital for combat aircraft maneuvera bility and control but are not neces sarily essential for_basic flight capa bilities Refer
150. e Filler Patch e Repair Doubler 1 Stop drill all cracks Figure 4 21 Skin Patch Cherry Rivets item 41 Appx Cover the damage with tape Be sure to cover the ends of all cracks PROCEDURAL STEPS 3 Fabricate a repair strap using thick sheet 1 Remove sections of the skin and frame or metal The sheet metal should be 2 X thickness bulkhead containing the damage Smooth and of the original 17 and stringer round the cutouts Figure 4 22 The strap should be wide enough to cover damaged area and to allow at least two rows of 2 Cut and fit repair doubler for frame or rivets on the skin and a minimum of six rivets in bulkhead Cut skin patch allowing overlap for at the undamage portion of damaged stringers The least two rows of rivets Repair patch and Strap should be long enough to overlap both doubler should be the same material and one ends of the damaged bulkhead or frame flange gauge thicker than original material by six rivets on each end In the areas where TM 55 1520 228 BD RF RAME STRAP 1 8 THICK SHEET METAL OR ANGLE STOCK 20 LONGER THAN LENGTH OF DAMAGE BULKHEAD HIDDEN SKIN DRILL STOP CRACK HOLES DAMAGED AREA TAPE RIVET LOCATION OF RIVETS OF 3 16 RIVETS STRAP WO SKIN DAMAGED AREA BULKHEAD FLANGE Figure 4 21 Repair of Damaged Bulkhead Flange 55 1520 22 80 RFRAME FASTENER SPACING IS F
151. e acceptable Also remove any damaged cracked or extremely hot cells leaking or spewing electrolyte WARNI NG Be extremely careful when removing or installing battery cells Bodily injury and equip ment damage may result if any metal tools or parts accidentally Figure 11 40 Battery Storage cause a short circuit BB 476 A Cell Layout 4 To remove bad cells use a 3 8 inch socket or equivalent to loosen and remove terminal screws Remove washers and terminal links remove indivi dual cells screw terminal screws back into each cell terminal grasp these screws with pliers and lift the cell straight up 11 40 TM 55 1520 228 BD ELECTRICAL AND AVIONICS SYSTEM 11 24 DAMAGED OR DEFECTIVE POWER RELAYS damage to the control circuit wiring Repair control circuit wiring With GENERAL INFORMATION A power relay is 24 28 V dc applied to terminals or an electrically operated switch between X2 of the power relay check the voltage the main bus and other electrical com between terminals Al A2 and the ponents in the aircraft The relays are aircraft fuselage ground Figure normally controlled by a switch in the 11 41 The voltage on terminals Al and cockpit Damage incurred to power A2 should be identical If there is no relays may be temporarily fixed by one voltage on either one of the two ter of two options m nals Al or A2 with the relay energized the relay should be considered a First option Rep
152. e considered direct replacements NTRODUCTI ON h In some situations petroleum oil lubricant POL substitute products of friendly or enemy nations can be used however CAUTION should be exercised due to the possibility of sabotage If there is no other alternative but to use enemy products check for signs of contamina tion discoloration smell and thickness i a product under consideration is identified as described above it will fall in one of three categories These categories are defined as follows 1 Primary products These are basic products for which the system was designed The system will function without limitation 2 Alternate Product These are products that closely match the primary product and may result in some reduced performance with no effect on system durability There are no limitations on duration of use 3 Emergency Expedient Products a These are products that can be used for only short periods of time These products are to be used as a lest resort These products will cause poor performance and system damage after pro longed use b It is important that the distinction between these categories is understood Since the choice between products could mean the difference between completing the mission and limping home TM 55 1520 228 BD APPENDIX D APPENDIX D Table 2 1 Essential Spare Parts NATIONAL STOCK NUMBER DESCRI PTI ON 2995 00 134 4543 Actuator Electro
153. e numeral one the letter E ENGINE INSTRUMENT shall not be used for circuit or Tailpipe temperature cable identification Fuel flow Fuel quantity GNI TI ON Fuel capacity Booster Oil temperature Vi brator Oil pressure Distributor Manifold pressure Electronic Fuel pressure Warning Engine oil quantity Tachometer Warning TM 55 1520 228 80 ELECTRICAL AND AVIONICS SYSTEM Table 11 2 Function and Designation Letters Cont CI RCUI T CIRCUIT DESI GNATI ON DESI GNATI ON LETTER CI RCUI TS LETTER CI RCUI TS K ENGINE CONTROL Q FUEL AND OIL Blower ratio Fuel valves Starter Fuel booster pump motor Warning Moisture control Oil dilution LIGHTING Engine primer Approach Fuel transfer pump motor Flasher coder and control Cockpit Fuel loading pump motor Drift Oil transfer pump motor Cabin and control Formation Oil booster pump Cargo Oil scavenge pump Interior Throttle control Instrument Fuel pump motor Section fuselage Oil diverter Landing Oil valves Exterior Warning Running position navigation Passing R RADIO Navigation and Search communi cation Taxi RA Instrument landing Warning RC Command MISCELLANEOUS ELECTRIC Windshield spray Windshield wiper Hoist Enclosure operation Positioner seat pedal Special test equipment UNASSIGNED n order to avoid confusion with the numeral zero the letter O shall not be used for circuit or cable identi fication DC POWER RD Radio direction finding RF VHF liaison
154. e that extends into a fastener hole or lightening hole a Damage Measurement of Typical Sections Record on DA Form 2404 1 The parameters involved in b Webs Panels and Skins measuring damage to typical sections are shown ih Figure 1 3 The per 1 Refer td Figures 4 3 and 4 6 tinent values are for the measurements of WL and D WL is the largest dimension across the CD Depth of damage damage regardless of direction and CL Length width of damage must include all radiated cracks D A CL x CD area of damage is the distance between damages Take D Distance between damages and record measurements as described in paragraph 4 7 2 In Figure 4 4 the length of the flat tened cross section of the angle is a b 4 7 55 1520 228 BD Figure 4 3 Evaluating Damage to Angles Channels and Z Angles 55 1520 228 BD CD a IE Remaining Area of Flattened Cross Section Damaged Area of Flattened Cross Section ROO Figure 4 4 Damaged Cross Section 1 9 55 1520 229 80 RFRAME gt M N Eo N SN AN S 45 WL SOON WL N MS YIN N WES N ONS NS NOS N N N bre N IMPORTANT MEASURED INCLUDE Figure 4 5 LATERAL DAMAGE MUST ALL RADIATED CRACK
155. ea ted TNO SIS cicjecjo c ef of of of ef of of of af of of of of of of of gt Gani tani Kami Eam Kami Kasai et ami Kam a taml Lam Lami Lani al a ae CION ac ws ejcjciciejejcieliejeicejejeejoejepnnh aie r fafa of of of ef of ol of of of of of of of of e mj be te Lam Lasd Lami ei a ied fed i i MIEN oja NW of wt 51 4 of ej af Z e mm an kuai tan Kani Kastani aa lasi kanl Gmi astana at mt en uni olcs s of sf of of of of ej of of of of of of of of of of ef e Cani iani Gaa Kani Lam Kasal Cami Cani mmi 1 1mm mI jmd o e od ex oc amp ir ele of of of wf of of of of of of of of of of of of tami kani tan Kan Lami amd Comal Kani Lan lam Lani lani lani ami Cored gig gt ol oc lt i ic I lt ci 1 85 0 o of af s ol of of of of of of of of Can Kam Can Comm lam Kami eed
156. ed to the integrity and performance of other aircraft systems and components Some of these effects have been con sidered and are reflected in the assessment standards 2 The assessor is responsible for working with other specialists to determine if damage to airframe structures will overstress damage or degrade the performance of other system components All of the system hardware near the damage should be evaluated for these possible effects Among the types of conditions to consider are as follows TM 55 1520 228 BD RFRAME a Structural movement which Classify the structure as failed even if might change the location or alignment the damage is within allowable of a component Controls and drive limit shafts will be particularly critica 4 14 BDAR REPAIR PROCEDURE INDEX b Structural damage which could affect the security of wire PARA bundles and fluid lines causing them to vibrate chafe and fatigue during Skin Stiffener Damage 4 16 flight Cap Skin Web Doubler Damage ex x a Oe LI c Damaged structure which Cap or Longeron Damage alu might interfere with the free travel or Frame Bulkhead Skin and movement of a system component during Stringer Damage o 14 10 Operation Honeycomb Core Floor or Panel Damage _ 4 20 3 If the assessor determines Windshield Window Damage 1 21 that structural damage will or might Tail Boom Skin Damage 4 22
157. ed Airline Damage M ITE TM 55 1520 228 BD APPENDIX F AVIONICS CONFI GURATI ONS N AT THE DISCRETION OF THE COMMANDER AUTHORIZED TRAINING FIXES ARE LISTED IN APPENDIX E IN EITHER CASE DAMAGES SHALL BE REPAIRED BY STANDARD PROCEDURES AS SOON AS PRACTICABLE Section l Fel SCOPE This appendix lists and depicts the major components cable routes and wiring terminations per taining to the OH 58 series helicopter avionics This information is fur nished as an aid to expedient repair techniques described in Chapter 11 F 2 GENERAL The actual configura tions may vary depending on particular requirements or changes incorporated through modification work order MWO action and special purpose alterations NTRODUCTI ON The Figures F l thru F 10 show typi cal location of avionics and their associated components in relation to the helicopter and lists the component part number Each figure also has a table associated with the avionics system which contains a complete wire listing to be used as an aid in rapid wire splicing This includes the wire number type shielded not shielded or pair twisted with shield end connectors and the pin numbers on each connector TM 55 1520 228 BD APPENDIX F F2 Figure F l Intercom System Sheet 1 of 2 TM 55 1520 228 BD APPENDIX F DRAW NG PART DESI GNATI ON NUMBER FUNCTI ON 1 TJ 11E 02 01 Module
158. efield damage to the OH 58 helicopter It directs you to an expedient BDAR fix or to the stan dard system fix of 55 1520 228 23 1 2 if an expedient BDAR repair does not exist General decision logic chart Table 2 11 assists in BDAR discussions b Each chapter will have a specific fault assessment chart for each func tional group and this flow chart will direct you to specific BDAR fixes for and within the functional group Use the following guidelines to find and fix sustained damage or suspected damage to your helicopter Keep in mind that damage can be sustained while on the ground or in flight The helicopter location can have a considerable effect on the assessment following appraisal shall be accomplished 1 If possible and time permits inspect and check the helicopter using operator s check list CL operator s manual 10 and other records and forms kept in aircraft log book At the same time be looking for obvious damage to aircraft INTRODUCTION 2 If applicable and possible use standard troubleshooting recommen dations in TMs 3 If you find a problem deter mine its effect on helicopter s mobi lity and capability 4 If you cannot fix the problem with standard fixes apply this TM and use general and specific assessment tables charts and BDAR action 5 If the damage does not affect aircraft s flying status the aircraft or flight commander will decide wheth
159. egnated rubber LIMITATIONS These repairs are tem porary and the damaged hoses should be replaced as soon as possible Inspect after every flight PERSONNEL REQUIRED Soldier e 15 Minutes MATERI ALS TOOLS REQUIRED e Glass Tape or Equivalent PROCEDURAL STEPS l Locate damaged area and remove panels and or other items as necessary to gain access to the duct to be repaired Refer Figures 15 2 and 15 3 for locations of flexible plastic ducts 1 Wrap glass tape several duct to cover hole or tear Tape should extend beyond damaged area 3 to 4 inches in each direction Section IIl 15 7 GENERAL INFORMATION Damage to some bleed air lines may be repairable SYMPTOM Loss of Engine Torque and or High Engine Oil Temperature LIMITATIONS Inspect after every flight PERSONNEL ME REQUIRED 1 Soldier 91 Hour MATERI ALS TOOLS REQUIRED e Sheet Metal Patch 0 016 in Min Sealing Compound item 4 Appx C e Aluminum Tape item 60 Appx Clamps 0 032 inch or Safety Wire 0 042 inch item 27 Appx C PROCEDURAL STEPS l Locate damaged area and remove panels and other items as necessary to gain access to the line to be repaired Refer to Figure 15 6 tor locations of bleed air lines turns around 3 BLEED TM 55 1520 228 BD ENVI RONMENTAL CONTROL SYSTEM Record BDAR action taken When mission is completed or as soon as feasible replace duct using standard
160. eiving Set AN ARN 123 V 1 OH 58C Wiring Table Radar Altimeter AN APN 209 OH 58C Wiring Table FF 72 58 jou S Wiring Table IFF APX 100 OH 58C Wiring Table AN APR 39 TM 55 1520 228 80 HOW TO USE THIS MANUAL This manual is developed to assist the soldier in a battlefield environment to make assessment and repair of damage to the OH 58 helicopter which cannot due to asset avallability or environmental factors be repaired in the normal prescribed manner Within this technical manual the word shall is used to indicate a mandatory requirement The word should is used to indicate a nonmandatory but preferred method of accomplishment The word may is used to indicate an acceptable method of accomplishment l Organization of the Manual This manual contains a general information chapter chapter 1 a general assessment chapter Ehapter 2 and specific repair chapters chapters 4 thru 19 Chapter 3 15 not used It also contains five appendices References Appendix A special or fabricated expendable durable supplies and materials list Appendix C substitute materials and parts Appendix D and BDAR fixes authorized for training Appendix 2 Chapter 2 is used to assess the helicopter in general and references specific chapters for detailed repair procedures of the major functional groups The major functional groups correspond with the functional groups of the 23 series manuals that
161. elivered to main and tail rotor at acceptable limits 2 Maximum engine torque 80 at 0 kts 64 at 16 kts 53 at 32 kts 50 at 50 kts 3 Lift capability for crew members Unload unnecessary weight 4 Flight controls at minimum function level acceptable for flight 5 Instruments avionics as required to meet mission needs 6 Maximum airspeed of 50 kts 7 Maximum flight duration of 2 hours Consideration will be given to minimize flight duration 8 Be prepared for emergency procedures See TM 55 1520 228 10 Chapter 9 WARNING Careful consideration shall be given to the operation of the Identify Friend or FOE IFF Mode 4 avionics system Failure of the IFF or failure to properly communi cate with area air defense command prior to liftoff could result in an attack from friendly forces due to mistaken identity 1 9 TRAINING a BDAR by its nature involves fixes bypasses and or jury rigging which is Section III 1 10 TAGGING IDENTIFYING BDAR REPAIRS a All damage will be identified on aircraft inspection and maintenance record DA Form 2408 13 and DA Form 2408 18 as per DA PAM 738 751 See 152 b Recording of BDAR repairs and the use of status symbols as defined in DA PAM 738 751 will be completed as soon as practical to indicate any limita tions and restrictions or required stan dard repairs c In addition to recording all damage the area damaged will be marked on aircr
162. en them A procedure to rapidly determine what is damaged whether it is repairable what assets are required who can perform the repair and where the repair can made A group of parts which could contain one or more unrelated parts of a subassembly one or more sub assemblies and attaching hardware Related to an axis Describes the linear distance shaft or gear moves Any incident such as combat damage random failures operator errors accidents and wear out failures which occur on the battlefield and which prevent the eguipment end item from accomplishing its mission A primary structural element designed to carry heavy loads by resisting bending in one direction Usually constructed with a channel tee or I cross section Any change in an intended configuration nside measurement of the interior diameter of a hole or tube Also used to describe the hole itself GLOS 1 TM 55 1520 22 80 GLOSSARY BOWED BOX BEAM BRAI D BREAK BRI DGI NG BRI NELLED BULKHEAD BUCKLE BURN BURNI SHI NG BURR CANNI BALI ZATI ON CAP CATASTROPHIC CHAFED CHECK CHIPPING CHORDLI NE GLOS 2 GLOSSARY Cont Curved or gradual deviation from original line or plane A primary structural element designed to carry heavy loads by resisting bending in at least two directions characterized by a Square or rectangular hollow cross section Machine woven wire strands Separation of a part or Substance from it
163. entials as low as 50 volts may cause death under adverse conditions TM 55 1520 228 BD ELECTRICAL AND AVIONICS SYSTEM CAUTION Make sure aircraft power is off Disconnect battery before touching any wires OPTION 1 Crimp Splicing LIMITATIONS Only to be used for wire sizes 12 26 Where no more than one splice is made per 10 feet of wire it is a permanent repair PERSONNEL TIME REQUIRED e 1 Soldier 10 Minutes MATERI 15 TOOLS REQUIRED e Appropriate Size e Appropriate Size Sealing Sleeve item 10 Appx B Crimping Tool item 10 Appx B Strippers item 10 Appx B Heat Gun item 10 Reflector item 10 Appx PROCEDURAL STEPS Splice item 10 1l Strip wires refer tq Table 11 3 Table 11 3 Unshielded Cri mp Splice Application STRI PPING TEMP WI RE SI 20 26 LENGTH RATI NG NCHES DEG 2 Slide sealing sleeve onto one of the wires Figure 11 2 On wire rated at 125 C or above insert one prepared wire into small end of sealing sleeve and push crimp barrel out 3 Crimp wires with crimp tool TM 55 1520 228 BD ELECTRICAL AND AVIONICS SYSTEM y MP PARRE PREPARED WIRE INSERTED SEALING SLEEVE NOTE SLIDE SEALING SLEEVE OVER CRIMP FOR WIRES 125 C OR ABOVE SEALING SLEEVE OVER ONE WIRE WIRES CRIMPED IN CRIMP BARREL FOR WIRES RATED 105 C OR BELOW Figure 11 2 Crimp Splice 11 8 TM 55 1520 228 BD ELECT
164. equires simplicity speed and effectiveness Some BDAR procedures include repair techniques that violate BDAR capa who are trained in assessing battlefield damage and field repair procedures 1 5 QUALITY DEFICIENCY REPORT EQUIP MENT IMPROVEMENT RECOMMENDATION ODR EIR If your helicopter and its quipment need improvement let us know Send us an EIR You the user are the only one who can tell us what you don t like about your equipment Let us know why you don t like the design Put it on an SF 368 Quality Deficiency Report Mail it to Commander U S Army Aviation Systems Command ATTN 5 4300 Goodfellow Boulevard St Louis MO 63120 1798 We ll send you a reply STANDARDS AND PRACTICES standard peacetime maintenance practices In a combat emergency situation greater risks are sometimes necessary and acceptable 1 3 55 1520 228 BD GENERAL INFORMATION 1 7 WAIVER OF PRECAUTIONS Under combat conditions BDAR may be performed on helicopters which are in flight or which are under power while on the ground While some of these BDAR actions may require waiving of safety precautions the cautions to protect personnel lif should not be overlooked Other similar precautions may be waived at the discre tion of the commander BDAR fixes may be required in a chemically toxic environ ment or under other advers battlefield conditions with severe limitations in personnel faciliti
165. er as shown in Figure 4 28 If damage is in an area where installing an interior patch is not possible or where sharp edges fromrivets on an interior patch might cause damage a single exterior patch plate 0 05 inch thick may be used Make plates 2 inches larger than the cutout Lay out and drill a rivet pattern two rows as shown 3 Assemble with 2 rows of cherry rivets 4 Record BDAR action taken mission is complete as Soon as practical repair the equipment system using standard maintenance procedures OPTION 5 LIMITATIONS This option is recommended for secondary structural areas which have a honeycomb core between the walls where repair is required for aerodynamic reasons or to keep water out of aircraft PERSONNEL TIME REQUIRED el Soldier 1 Hour MATERIAL TOOLS REQUIRED ePatch Plate 0 020 Inch Mi ni mum Al umi num or Ste el eCherry Rivets Te 38 Appx Sealant item 5 Appx When Secondary Structure Repair Rivet Gun 4501 en 7 Appx C Dri and Bit TM 55 1520 228 BD Al RFRAME 00 5 INNER SKIN Figure 4 26 Damage Repair Accessible One Side Only MAKE PATCH FROM 2024 T3 OR 7075 T6 ALCLAD ALUMINUM 1 8 CHERRY RIVET 2 DIA EDGE DISTANCE 4 DIA RIVET SPACING THRU ONE SKIN ONLY REPAIR PATCH _OUTER PATCH AND FASTENERS WITH SEALANT 8 FILLER COMPOUND NOTE MAKE INNER PATCH INNER PATCH SAME DIA AS HOLE
166. er to fix or defer fix and continue or start mission 6 If damage does affect flight status do one of the following a Replace damaged part with a serviceable part b Replace damaged part with suitable substitute if it exists c Apply a BDAR fix 7 After repairing the damage replace all lost fluids lubricants If one specified by aircraft TM is not available refer tp Appendix D for alternative materials parts 2 1 TM 55 1520 228 BD ASSESSING BATTLEFIELD DAMAGE Table 2 1 General Decision Logic AIRCRAFT SUSTAINS OR SUSPECT DAMAGE IN FLIGHT ON GROUND NO YES IN FLIGHT GROUND ASSESSMENT ASSESSMENT AND REPAIR FORCED CAN AVUM FIX LANDING CONTINUE MISSION CONTINUE FLIGHT FORCED CAN AVIM FIX LANDING YES NO FLIGHT ABORT RETURN TO BASE MISSION NO MISSION COMPLETE EVACUATE CANNIBALIZE DESTROY ACFT ACFT ACFT SEE TM 55 1520 328 25 d General aircraft assessment charts Table 2 1 guide you through the air craft s capability so that all the necessary capabilities are evaluated If a fault is found fable 2 T directs you to the chapter for the functional group which contains the fault The BDAR assessment procedure will refer you Section II 2 2 chart GENERAL FAULT ASSESSMENT TABLE Table 2 2 AIRCRAFT IS NOT 100 FULLY MISSION CAPABLE NEEDED FOR THE MISSION TS ARMAMENT EQUIPMENT YES NO INSPECT AIRCRAFT
167. ergency flight repair MATERI ALS TOOLS REQUIRED Mechanical Repair Sealing Clamp 3 or 5 inch Knife The repairs spe FUEL CELL DAMAGE PROCEDURAL STEPS 1 Defuel the fuel cell by the following procedure a Remove the fuel drain cover panel b Push or twist drain valve located under aircraft where fuel pump is located c Place a bucket or any type recep tacle under the aircraft to catch the fuel 2 Locate the damage e g hole or tear on the cell NOTE For holes less than 2 inches across use the 3 inch clamp For holes greater than 2 inches across but less than 3 inches across use the 5 inch clamp Holes larger than 3 inches are nonrepairable 3 Use the knife to enlarge the hole to 3 4 inch to 2 inches maximum for a 3 inch clamp and 1 inch to 3 inch maxi mum for the 5 inch clamp 4 Insert the bottom plate of the clamp through the hole and pull up using the cord Position the plate so the hole is entirely within the gasket area Slip the top plate over the threaded stud and hand tighten the wing nut Figure 12 2 CAUTI ON Excessive mechanical tighteni ng of the wing nut can result in failure of the clamp The wing nut shall be finger tightened and the maximum torque on the wing nut shall not exceed 10 to 12 inch pounds 5 Tighten drain valve and instal cover plate TM 55 1520 228 BD FUEL SYSTEMS REPAIR CLAMP POSITION BOTTOM PLATE OF REPAIR CLAMP INSIDE DAMAGED
168. erial Performance of a practical functional action A specific BDAR repair technique often non standard in nature The process of repairing or adjusting a machine to restore improve or lengthen its useful life urface finishes such as coatings A breaking away of s flaking of large pieces of such material or platings or A group of electrical wire strands twisted together Small holes or indentations generally caused by rust corrosion high compressive stresses or metal to meta pounding A repeated or customary action The major structural load carrying elements of an airframe without which helicopter flight safety would be compromised A particular course of action A series of actions conducive to an end The box shaped structural area surrounding the helicopter main transmission This area carries several primary structural loads REASSEMBLY RECOVERY REMOVE REPAIR REPLACE REWORK RUPTURE SCOR NG SCRATCHING SECONDARY STRUCTURE SELF RECOVERY SEMI MONOCOQUE SERVI NG SKIN 55 1520 228 BD GLOSSARY GLOSSARY Cont The assembling and aligning of all 5 parts into a complete assembly to af item of equipment ubassemblies and fect a serviceable The retrival of immobile inoperative or abandoned helicopters from the battlefield or immediate vicinity and its movement to a maintenance collection point main supply route or a maintenance activity for disposition repa
169. es equipment and materials Performance of repair tasks may be necessary while wearing protective gear Decontamination procedures are described in FM 3 5 1 8 OPERATING CHARACTERISTICS This manual covers expedient repairs for the OH 58 helicopter and its components It is entirely possible that in a combat Situation the helicopter having under gone one or more repairs may suffer degradation of its normal operating characteristics e g reduced speed reduced load capability reduced range etc and still be able to carry out all or parts of an assigned mission The minimum functional combat capability MFCC criteria for the OH 58 is as follows a Flight Capability for Mission Completion Helicopter s flight charac teristics degraded to a minimum of combat capable CC 1 Sufficient power delivered to main and tail rotor to accommodate lift capability for helicopter crew and cargo 2 No fuel leaks which will cur tail the intended length of flight 3 No degradation of any com ponent system which will end in failure and curtailment of intended mission 1 4 4 Communications Must have intercom communications within aircraft and at least two tactical receiver transmitter R T units operating at full capability NOTE Criteria may be waived for recovery or if the tactical situation demands otherwise b Flight Capability for Self Recovery Capability SRC 1 Must have power d
170. ese elements Separation of a part or piece of material from itself Loose or raveled threads and fibers The ability of the helicopter to perform ALL its combat mission assignments Major helicopter subsystems identified in and corresponding to functional groups in TM 55 1520 236 23 The central main body of the helicopter GALLI NG GAP 00 61 NG HEAT DISCOLORATION HE HOUSING NDENTATI ON NSPECTI ON NTERFACE JURY RIGGING LIMIT LOAD PATH LONGERON LRU MAI NTENANCE COLLECTI ON POINT MAI NTENANCE SUPPORT TEAM MST TM 55 1520 228 BD GLOSSARY GLOSSARY Cont Aggravated condition of wear generally caused by a rubbing action with little or no lubrication Clearance between faying surfaces measurement of which is used to determine thickness of shims Removal of surface metal because of mechanical contact with foreign material A change in color or appearance of a part caused by excessive temperature High explosive incendiary armament round A frame support or cover used to hold parts of machinery in place Also used as a protective cover A cavity with smooth bottom or sides on rolling contact surfaces which can occur A critical examination of parts to determine their use fulness or condition The joining point of two flat surfaces rapid non standard method of repairing an item repair technique An established point or boundary in time speed
171. essment paragraph 4 5 a detail assessment and a repair plan The initial assessment is a quick visual assessment to decide whether or not a detail assessment should be made A detail assessment involves the identification of all damage to primary structural elements possibly some clean up and measurement of the damage and of the damaged ele ments The procedure is described for various aircraft sections in this chapter This process requires damage measurement and determination of the corresponding damage limits The repair plan is based on an analysis of the detail assessment An overall view of all the aircraft zones is shown in 4 5 INITIAL ASSESSMENT To perform an initial assessment the assessor must be acquainted with structural damage modes and the primary structure as shown in the figures of this chapter He shall be capable of differentiating between primary and secondary structure and he must understand the function of primary structural elements The initial assess ment consists of a visual inspection of primary structure The assessor deter mines if any primary caps webs or panels are damaged or fractured and decides whether 4 1 TM 55 1520 228 BD AIRFRAME Table 4 1 Aircraft Structure Damage Assessment Prodecures STRUCTURAL DAMAGE PRIMARY OR SECONDARY STRUCTURE SEC I MAKE INITIAL OR DETAIL ASSESSMENT AND REPAIR PLAN SEC I TS DAMAGE WITHIN ACCEPTABLE LIMITS
172. evered ends of cable for being repaired after the center conduc pigtail method of shield terminations tor is repaired Shielding material can Figure 11 16 step a be obtained from another shield cable or ground cable material 2 Splice center conductor Fi gure step b using a permanent splice NOTE or by using one of the splicing proce dures in paragraph 11 9 t is essential that the shielding as well as the inner conductor be 3 Use two splice connectors to add repaired properly to prevent elec short length of insulated wire as exten tromagnetic interference EMI sion to complete shield connection problems Figure 1l 16 step b 3 Splice center conductor using a per 4 Insulate repair Figure 11 16 manent splice or by using one of the step c splicing procedures in paragraph 11 9 Figure 11 17 step b Insure center 5 Record BDAR action taken When conductor is insulated from shield mission is complete as soon as practical repair the equi pment system 4 Slide shielding material over using standard maintenance procedures repaired inner conductor and clamp at shielding overlap areas Figure 11 17 OPTION 4 Substitute Shielded Braid step c LIMITATIONS This is a temporary 5 Record BDAR action taken When repair mission is complete as soon as practical repair the equi pment system PERSONNEL TI ME REQUIRED using standard maintenance procedures 1 Soldier e 1 2 Hour Per Wire 11 9 SHIELDED CABLE REPAIR SEG
173. f any of the following conditions exist 1 Damage to the fitting exceeds the limits contained in Tables 4 2 thru 4 7 or if damage 1s not tabulated and exceeds 20 percent of the structural section in any one location 2 One or more fasteners con necting the fitting to a structure or to an aircraft component are bent sheared stripped or loose f Evaluation of Splices Straps Doublers and Gussets Damage to a splice strap doubler and gusset wil be evaluated as part of the elements to which it attaches Classify a splice strap doubler or gusset as failed if any of the following conditions exist 1 Damage exceeds the limits con tained in Tables 4 2 thru 4 7 or if damage is not tabulated and exceeds 20 percent of the structural section in any location 2 The part has significant damage at the intersection of the two members it connects 3 Fasteners securing the part to a structural member s are sheared pulled through or missing at two or more adjoining locations 4 More than 20 percent of the total number of fasteners are similarly damaged 4 29 TM 55 1520 228 BD Al RFRAME Evaluation of Damage to Skin and Web Panels Classify a skin or web panel as failed if any of the following conditions exist 1 Damage exceeds the limits con tained in Tables 4 2 4 7 or if damage is not tabulated and exceeds 25 percent of the panel area 2 Damage to one panel is located wit
174. f cannibal ized components 3 Destroyed This is a last resort These conditions apply to the primary structure and should not be con fused with the mission capability classifications Mission capability is dependent on equipment condition TM 55 1520 22 80 Al RFRAME d The type extent and variation of b Repairs on damaged struc damage under condition 3 does not per tural elements that are better than mt categorization of the many com condition 1 may be deferred except for binations of damage Self recovery if cleanup and smoothing considered will depend on the extent and type of damage type of terrain e If the worst case is between distance and urgency of the situation condition 2 and 3 a decision must be made to degrade the aircraft to If judgment and experience indicate condition 3 or to repair the aircraft self recovery is feasible it should be and restore it either to condition 1 accomplished at mini mum wei ght altitude 07 2 An aircraft in this condition is and airspeed with an occasional stop to probably so badly damaged that it may check on the condition of the aircraft not be restored to condition 1 within the available time However every 4 10 REPAIR PLAN effort should be made to restore it to condition 2 or better if at all possible a The damage measurements and ini for recovery tial repair data obtained from the detail assessment must be organized and 1 If the aircraft is degraded to formulated
175. fer to Table 11 5 2 Slide the tubing inner sleeve and filler sleeve onto one of the coax cables in the order given 3 Splice the center conductor Use the red cavity of the crimp tool 4 Shrink the filler sleeve over the splice Use reflector temperature set at 900 F Keep hot air away from shield Sleeve and tubing 5 Center and shrink the shield sleeve over the splice area so that the solder melts and flows figure 11 29 Shield Sleeve must overlap coax braid at both ends Use same reflector and tem perature Keep hot air away from tubi ng 6 Center and shrink the tubing over the splice area Use reflector with temperature set at 900 F Coax Splice Inner Sleeve Coax Splice Shield Sleeve 1 Record BDAR action taken When mission is complete as soon as practical repair the equi pment system using standard maintenance procedures SHIELD OVERLAP SHIELD SLEEVE Figure 11 29 Coax Splice with Tubing Sleeve 11 18 RG 233 0 COAX SPLICE FOR RG 58C U RG 59B U AND RG 71B U GENERAL INFORMATION There are various coax splices in the wiring repair kit that may be used for the different types and sizes of coax cable LIMITATIONS This is a temporary repair PERSONNEL TI ME e 1 Soldier 15 Minutes REQUI RED 11 31 55 1520 228 BD ELECTRICAL AND AVIONICS SYSTEM MATERI ALS TOOLS REQUIRED e Coax Splice item 10 Appx B Stripper or Knife Reflector item
176. ft Strap 0 31 73 00 18 30 13 30L amp R Tube Forward 0 10 02 trap 73 00 amp 18 308 13 30L amp R Back Up Supports 130 00 20 75 amp 73 00 amp 18 30 amp 13 30L amp R Attachment Damage Allowed On 130 00 20 75 amp Fasteners and Inserts One Fastener amp Insert Per Fitting Jacking amp Fitting Damage Limited By Tiedown Fittings Jacking Tiedown Requirements Anti Torque 5 04L Fitting Collective Fitting Jackshaft Bearing No Damage Allowed Support 73 12 28 62 1 50L Anti Torque Fitting 3Nvadaiv 9 8 0 0 91 99 WL 96 Table 4 3 Damage Limits Fuselage Condition DAMAGE LIMIT LOCATION gt COMPONENT ELEMENT FLANGE SKIN WEB NOTES MEMBER CAUTIONS Upper Longeron 130 00 72 00 14 12 Channel D N x CL DENxWL 205 00 72 93 4 72L amp R No Damage Allowed 130 00 amp 900 Boom Attach Fittings No Damage Allowed Center Longeron 130 00 51 67 25 5 Angle and Channel 13000 5167 No Damage Allowed 100635 61 76 2 Boom Attach Fittings No Damage Allowed Lower Longeron 130 00 29 40 22 50 Angle 222 13000 2940 Splice No Aft Fuselage 130 00 Lower Longeron pue 130 00 Lower Longeron 206 95 to Upper 3 0 Longeron 130 00 Lower Longeron Doublers 206 35 Upward 130 00 Lower Longeron Clips me Tail Boom Access Door 192 84 73 34 Skin 5 205 7
177. ge Count the number of damages and measure the D between damages Start with the worst dama Record these values for each damage element on DA 2404 and compare them with the allowable damage limits given in this section Select the set of allowable damage limits which are next larger than the measured damage deter mne the corresponding condition Consider whether damage could result in flight failure of other elements Attempt to visualize what effect large defections of damaged member will have on adjacent structure e cc C Decide on whether repair can be deferred or whether damage should be fixed and what the condition of deferred or repaired damage would be TM 55 1520 228 BD Al RFRAME AFT FUSELAGE LANDING GEAR FORWARD FUSELAGE STABILIZER TAIL BOOM Figure 4 8 0 58 Helicopter 4 17 55 1520 228 BD AIRFRAME 11707 120 44733 COWL ROOF INTERSECT HELICOPTER 255 589 48 61 2450 11707 PITCH CHANGE AXI SE AXIS 107 128 wi 117 598 Q TAIL ROTOR he 4 TOP OF BOOM 9350 Mast we 9308 9046 205 034 12608 124 2 1 19176 14 e 24 FWO FIREWALL w 7s osel 5624 2o queas Ei 490 as FIREWALL 3302 I r 455 71 54 445 8127 wi 76 50 153 M d we 4 f H 7 iU nom qi SOOM 11 221 we 2 T taS WL Y FA 105 w TE SZ
178. ge assessments should consider them as guides and balance the damage limits against the judgment resulting from their own experience a Damage limits are tabulated in Taies thru 4 7 for most primary structure If a damaged member is not Covered in this manual and the damage appears to exceed authorized limits classify the member as unserviceable b A component that shows signs of severe overstress such as twisting or buckling or heat damage should be treated as failed c A component should be repaired if the failed component can overstress other systems d Evaluation of Damage to Caps Longerons and Stringers Classify caps longerons and stringers as f if any of the following conditions exist ailed 1 Damage exceeds limits tabulated in Tables 4 2 thru 4 1 2 There is damage in four or more locations within a length of three feet 3 Fasteners securing the com ponent to other major components are sheared pulled through or missing at one or more locations 55 1520 228 BD Al RFRAME 4 Three or to each other longeron sheared more fasteners next which join a cap and stringer to the web pulled through or missing are 5 Twenty percent or more of the component to web fasteners are similarly damaged 6 Angles and clips securing the component to another structure are severely damaged or failed e Evaluation of Damage to Machined Fittings Classify a fitting as failed i
179. ge causing a structura element to weaken and permanently loose its original shape The sheet metal membrain connecting the upper and lower flanges of a beam or spar Provides overall rigidity to the airframe structure The tendency of a bent shaft to rotate away fromits Original center as the shaft RPMis increased thus Causing severe vibration 55 1520 228 BD Order of the Secretary of the Army CARL E VUONO General United States Army Official Chief of Staff THOMAS F SIKORA Brigadier General United States Army The Adjutant General DISTRIBUTION To be distributed in accordance with DA Form 12 31 AVUM and AVIM Maintenance requirements for OH 58A and OH 58C Helicopter Observation U S GOVERNMENT PRINTING OFFICE 1991554 122 21097 These are the instructions for sending electronic 2028 The following format must be used if submitting an electronic 2028 The subject line must be exactly the same and all fields must be included however only the following fields are mandatory 1 3 4 5 6 7 8 9 10 13 15 16 17 and 27 From Whomever lt whomever wherever army mil gt To 2028 redstone army mil Subject DA Form 2028 From Joe Smith Unit home Address 4300 Park City Hometown St MO Zip 77777 Date Sent 19 OCT 93 Pub no 55 2840 229 23 Pub Title TM 10 Publication Date 04 JUL 85 11 Change Number 7 12 Submitter Rank MSG 13 Submitter FName Joe 14 Submitter MName
180. ged power relay and install mounting hardware 5 Install wires and bus bar on correct terminals and secure with hardware 6 Record BDAR action taken When mission is complete as Soon as practical repair the equipment system using standard maintenance procedures OPTION 2 Creating a Jumper for Damaged Power Relays CAUTION Do not jumper battery relay on an aircraft This procedure is to be used only for one time emergency evacuation and recovery of 0H 58 11 42 LIMITATIONS Emergency repair No control over jumpered power relays circuit cannot be turned on or off PERSONNEL REQUIRED 1 Soldier 20 Minutes MATERIALS TOOLS REQUIRED Appropriate Size Aircraft Type Wire Appropriate Size Terminal Lugs PROCEDURAL STEPS L Disconnect battery 2 Figure 11 43 Type A and B shows two typical power relay configurations with Jumper This may be used as an aid in performing steps 3 thru 7 NOTE Use wire with the same gage or larger than the one being replaced 3 Prepare a jumper wire Figure 11 44 A 1 2 to 1 foot length of appropriate size aircraft wire with appropriate size terminal lugs crimped on each end 4 Locate terminals marked Al and 2 on power relay Power relay terminals should be marked on case of relay If markings are illegible Al and A2 ter mnals will be the ones with the largest diameter terminal studs 5 Remove hardware from terminals 1 and A2 6
181. ged structural Attach DA Form 2404 to DA Form 2408 13 elements that are below condition 1 and indicate deferred repairs on DA Form 2408 13 TM 55 1520 228 BD RFRAME 4 11 GENERAL The aircraft consists of three main sections The forward cabin sec tion extends from the cockpit nose at 51 to the bulkhead aft of the passenger compartment at F5130 The aft cabin section extends from 5130 to 5205 where the tail boom is attached The third section is the tail boom Refer to Figure 4 6 b The forward section utilizes alu m num honeycomb and sheet metal struc tures for the major load carrying elements The forward section provides for pilot and passenger seating fuel cell enclosure and pylon support Honeycomb sandwich is used extensively in this section including the upper and lower shells seat panels and some bulkhead panels The remainder is of conventional thin sheet metal construc tion Primary loads forward of FS73 are taken by the lower console pedestal and lower shell The cabin enclosure section between FS73 and FS130 is a X Z planar frame consisting of the center post at FS73 roof beam lower shell and bulkhead and enclosure at FS114 and F5130 Refer to C The aft section utilizes an alumi num and honeycomb semimonocoque construc tion and provides a deck for engine installation and a compartment under the engine deck for electrical equipment This section utilizes conventi
182. h options for a faulty component will be flight would be required to replace or repair by normal proce dures Those limited repairs which PERSONNEL TIME REQUIRED have been developed are listed in this Soldiers section 15 Minutes 7 6 ROTOR BLADE HOLE 1 INCH MATERIALS TOOLS REQUIRED DIAMETER OR LESS 1 SE or Alumi nized ape item 50 Appx C GENERAL INFORMATION A small hole Cleaning Solvent item 7 Appx passing through the honeycomb core area on either a main or tail PROCEDURAL STEPS rotor blade can be repaired with duct tape Removal of blade is not necessary 1 Position blades for access to amaged area Support blades to prevent movement and droop 1 1 TM RO 1 2 55 1520 228 BD TORS Pitch Link Lever Idler Link Swashplate Assy Link Collective Lever Inner Ring Outer Ring Collar H 3 r3 Lr C UA ROO we Lr c Blade Latch Blade Assy Retaining Bolt Grip Mast Nut Hub Assy Oil Lubricated shown Pitch Horn Mast Figure 7 1 Main Rotor System oo Ne TM 55 1520 228 BD ROTORS Hub Pitch Horn Blade Tail Rotor Gearbox Figure 7 2 Tail Rotor System 1 3 55 1520 228 BD ROTORS Table 7 1 Assessment Procedures MA AIL ROTOR BLADE ASSEMBLIES SUSTAIN DAMAGE IN FLIGHT VISUALLY INSPECT DAMAGE EVACUATE AMAGE REPAIRABLE NO CANNIBALIZE DESTROY REPAIR REPLACE MAIN OR TAIL ROTOR BLA
183. h bare wires on expe dient antennas with the radio keyed You could get burned and or shocked OPTION 1 LIMITATIONS Some loss of antenna gain and radio transmitter power PERSONNEL TI ME 1 Soldier 30 Minutes Use of Substitute Antennas REQUI RED MATERIALS TOOLS REQUIRED None PROCEDURAL STEPS 1 Be sure that FM No 1 1 AN ARC 114 circuit breaker and BAT switches on the overhead console are off 2 Remove vent screen from left side of horizontal console to obtain access to No 1 FM radio connectors CAUTI ON Do not pull on cables when dis connecting cable connectors Be careful to avoid any unneces sary strain on the cables NOTE If No 2 FM radio and secure voice control indicator are not installed blank panels may be removed to obtain additional access to con nectors 3 1 cable connectors from J1 2 J3 and 4 With a screwdriver turn the six fasteners that secure the unit to the mounting panel one quarter turn counterclockwise 5 Slide the No mounting panel 1 FM radio out of the 6 Locate coax cable 2 ARC 114 1014 stored in console and use it to replace coax cable 1 ARC 114 101A Connect it to J2 NOTE Both left and right hand homing antennas may also be used as emergency transmitting anten nas by using either coax cable 1 ARC 114 102A or 1 ARC 114 103A connected to J2 TM 55 1520 228 BD ELECTRICAL AND AVIONICS SYSTEM To replace No 1 FM r
184. he total time clock hours required to make the repair 8 Establish the priority of the fixes 9 Decide where the fix shall be performed 10 Decide if recovery or evacua tion is necessary and to what location d Fully Mission Capable FMC The helicopter can perform all its combat missions To be FMC the helicopter must be complete and fully operable with no faults listed in the aircraft inspection and maintenance record as prescribed in DA PAM 738 751 e Combat Capable Equipment meets the minimum functional combat capability requirements See paragraph 1 8 f Combat Emergency Capable The equipment meets the needs for specific tactical missions however all systems are not functional Also additional 55 1520 228 BD GENERAL INFORMATION Self Recovery The ability of a battle damaged helicopter to retrieve itself fly out from a battlefield environment It usually will involve flying with degraded flight status and with restrictions and limitations placed on performance characteristics such as limitations placed on weight airspeed damage due to the nature of an expedient repair may occur to the equipment if it is used The commander must decide if these limitations are acceptable for that specific emergency situation 6 Cannibalization or Controlled Exchange Throughout this manual can nibalization and controlled exchange are used interchangeably meaning the removal
185. hin 3 inches of damage in an adjoin ing panel 3 The panel or buckled is severely deformed 4 Damage to a panel exceeds the damage limit The damage extends across a stringer frame or former in an ad joining panel Classify that panel as E even if its damage is within imi ts 5 The panel is on the outside of the aircraft where the damage is exposed to aerodynamic forces that can produce ee or tearing of the structure in ght 6 Fasteners securing the pane are sheared pulled through or missing at three or more adjoining locations 7 Twenty percent or more of the total number of fasteners are similarly damaged h Evaluaton of Damage to Honeycomb Sandwich Panels Classify a honeycomb sandwich structure as failed if any of the following conditions exist 1 Damage exceeds limits tabulated in Tables 4 2 thru 4 7 2 The panel is damaged to the extent that it cannot support the weight of personnel cargo or equipment for which it was designed 3 The panel is on the outside of the aircraft where it is exposed to aerodynamic forces and the damage is 4 30 Oriented so as to produce peeling or tearing of the structure in flight 4 The panel is secured by mecha nical fasteners Three or more adjoining fasteners are sheared through or missing pull ed 5 Twenty percent or more of the total number of fasteners are similarly damaged i Evaluation of Damage to Sheet Metal Ribs
186. hown in Figure 7 5 LIMITATIONS Adjustment of blade balance may be required after repair Inspection of repaired area after each flight would be required PERSONNEL TI ME 2 Soldiers 1 Hour REQUI RED 1 6 REQUI RED Army Green Tape Maximum Width Available 3 Inches Mini mum or Aluminized Tape item 50 Appx C Fiberglass or Aluminum Wafers Aluminum Foil or Other Filler Material item 18 Appx C Adhesive Package PROCEDURAL STEPS L Position blades for access to damage area Support blades to prevent movement and droop 2 Smooth damage remove all rough edges j Clean area around damage and com pletely around blade where tape is to be applied 4 Make a plug of crushed aluminum fol or other filler material shaped to fit in the hole Do not make the plug too dense voids should be about 1 4 Inch Apply spots of adhesive to the aluminum sheet before crushing so plug will have some strength Apply adhesive sparsely to the finished plug in the area where it will come in contact with the blade sandwich material 5 Insert plug in hole Hole should be well packed 6 Cut out a fiberglass or alum wafer so it just fits over the hole without overlapping the external blade skin Apply adhesive to the bottom of the wafer where it comes in contact with the aluminum plug and close the hole 7 Cover hole with Army green tape Tape should extend 2 inches beyond edge of the hole Figure 7 4
187. ially dangerous con dition may exist The condition will be corrected as soon as possible 4 Red diagonal This symbol indicates a defect exists that is not serious enough to ground the aircraft 55 1520 228 BD GENERAL INFORMATION e Maintenance of Forms Instruc tions for the maintenance of forms records and reports are listed in DA PAM 738 751 and TB 55 1500 307 24 When battle damage assessment and repair BDAR becomes necessary the procedures in DA PAM 738 751 will apply Refer to and 1 2 for examples 1 In block 17 of DA Form 2408 13 list the fault 2 In block 16 of DA Form 2408 13 enter the status symbol 3 In block 18 of DA Form 2408 13 nter the corrective action taken 4 The individual completing the repair will sign the form in block 19 opposite the first line of the action taken and will place his last name ini tial over the status symbol in block 16 f Temporary Repair If the repair is temporary take the following addi tional action 1 In block 18 of DA Form 2408 13 enter the corrective action and a state ment that the repair is temporary Then make an entry in DA Form 2408 14 block b The entry will be a duplicate of the entry in block 17 of DA Form 2408 13 to include a statement that a temporary repair has been made NOTE Faults with status symbol of red x or circle red x will not be entered on DA form 2408 14 2 If the temporary repa
188. ice either inner or outer whichever is more Suitable and drill at least two bolt rivet holes on each end of the tube Refer td Table 13 3 for bolt drill sizes to use on different size tubes Holes should go through the splicer and the damaged tube and should i positioned in a cross pattern 13 7 Make sure that the origina center to center length b Figure 13 6 is maintained 13 4 5 Reinstall tube after repair is accomplished and check for binding or interference by manually moving the appropriate controls cyclic collec tive or pedals 6 Record BDAR action taken When mission is complete as soon as practical repair the equi pment system Using standard maintenance procedures OPTION 2 Fabricating Tubes Flight Control LI MI TATI ONS PERSONNEL TI ME Inspect after every flight REQUI RED e 1 Soldier e 3 Hours MATERIALS TOOLS REQUIRED e Tube Stock about same dia as original tube 0 032 in min wall thickness e Drill and Bit PROCEDURAL STEPS L Put aircraft flight control system into neutral rig 2 Remove damaged flight control tube Figure 13 8 3 On the end that fits into the clevis bolt mash the tube so that it fits into the arms of the clevis A small amount 0f clearance between the clevis arms should be allowed Figure 13 9 Round off the end of the mashed tube Figure 13 10 Drill a hole through the tube and install the bolt 4 On the end where the cle
189. ie cu s Bt ale che c VEG Cerca TID neo 6 7 Operating 1 8 0 Damage TV cT Se Ca ys 291 12 5 O Ring Packing and Gasket Applications 9 10 A a I 0 Quality Deficiency Report Equipment Improvement Recommendation 1 5 NDEX 3 TM 55 1520 228 BD NDEX INDEX Cont Subj ect Repair Plan Airframe Repair Procedure Index Airframe Alighting Gear Drive Train System Electrical and Avi oni cs System Environmental Control System Flight Controls Fuel Systems Hydraulic Power PEENE lt dk 3 uR Gp Vd Rotors 5 Utility System Reports Rigid Plastic Ventilation Duct p ed Rotor Blade Hole 1 Inch Diameter Qr Less 5 Sensitivity of Drive Train System to Battlefield Shield Terminators Shielded Cable Repair Shielded Cable Repair Skid Damage Ski n Stiffener Damage Splicing Unshielded Wires Structural Damage Assessment and Repair Substitute Emergency Antenna Field Expedi ent Supplementary Emergency Equi pment Information I Tagginglldentifying BDAR Repairs Tall Boom Skin Damage 5 25 Tail Rotor Gearbox Bullet Damage Terminal Boards T Terminal Lugs Terminators for Nickel Plated Shields Training E Transmission Bullet Damage apr Transmission Oil Air Duc
190. in system does not lend itself well to limited repairs In most instances the only repair options for a faulty component will be to replace or repair by normal procedures Those limited repairs which have been developed are listed in this section Section 11 8 5 SENSITIVITY OF DRIVE TRAIN SYSTEM TO BATTLEFIELD DAMAGE The drive train system includes a number of components which if damaged or deformed bent in any way or fail internally will render the system inoperable or severely degrade flight characteristics or safety The system is particularly sen sitive to any damage which adversely affects any of the following nter nal operation of transmission freewheeling assembly or tail rotor gearbox b Operation of the transmission oi system Drive Train Damage Drive Train Component ransmssion 01 Duct Repair s s 011 Pressure Transmitter Lea Low Pressure Sensing Switch 011 Hoses and Lines Leaks or Restrictions Dama 001110 Air Transmission Bullet Damage 8 10 Tail Rotor Gearbox Bullet Damage 8 11 REPAIR C Straightness original shape or integrity of either the mast drive shafts or output shaft at tail rotor gearbox 8 6 AIR DUCT HOSE DAMAGE GENERAL INFORMATION Holes distortions in air duct hose 16 tears required amount of cooling air reaching the oil cooler 2 Figure 8 2 This condition may cause the transmission oil system to operate at abo
191. inches in diameter around the wound on the out side and fill in the wound with adhe sive NOTE There must be a mini mum of a 1 2 inch bond ep 11 Apply the solvent soaked fabric patch to the outside surface by passing the cord through the hole in the patch and position the patch over the wound Smooth the patch into the adhesive 12 Pull the cord and tape to the structure keeping a slight tension 13 Do not disturb the repair for a minimum of 30 minutes and let cure two hours before refueling Cut the string and plug stem without disturbing the repair 14 Tighten drain valve and install cover plate 15 Refuel 16 Record BDAR action taken mission is complete as soon as practical repair the equi pment system using standard maintenance procedures the aircraft When OPTION 4 Two Plane Repair Damage a two plane area will be repaired in same manner described option 3 except the hole should not be enlarged to more than 1 2 X 2 1 2 inches OPTION 5 Three Plane Repair Damage to a three plane area will be repaired in the same manner as described in option 3 except the hole should not be enlarged to more than 1 2 X 2 1 2 inches and the rubber plug will be cut as shown MENEER This will allow the plug to assume the contour of the tank when pulled into place to the NYLON THREAD 20 INCH LONG TM 55 1520 228 BD FUEL SYSTEMS RUBBER PLUG KNOT APPROX 10 0 ADHESIVE Figur
192. ing unserviceable in flight 4 Fasteners securing the fairing and cowling are sheared stripped pulled through or missing at three or more adjoining locations 5 Twenty percent or more of the total number of fasteners are similarly damaged 6 There are large cracks or holes in an area of the fairing and cowling exposed to the windstream and peeling or tearing of the material in flight is probable 1 Evaluation of Damage to Firewalls Classify a damaged firewall as failed if any of the following conditions exist 1 The firewall shows sign of severe overstress such as buckling and misalignment 2 Fasteners securing the fire wall to the upper deck structure are sheared stripped pulled through or missing at three or more adjoining loca tions 3 Twenty percent or more of the total number of fasteners are similarly damaged 4 Damage to the supporting frame work causes the firewalls to be loose and subject to collapsing in flight 5 There are large holes or cracks in the firewall that would pre vent the firewall from containing a fire m Assessing the Effect of Structura Damage on Other Aircraft Systems 1 The assessment standards pro vided basically concern the air worthiness and flight capability of the 0H 58 airframe However every member of the airframe has a structural and or functional purpose Even those members which are unessential to airworthiness may have an important function relat
193. inned against another object Watch your footing NOI SE Sound pressure levels in and around this aircraft during operating conditions exceed the Surgeon General s hearing conservation criteria as defined in TB MED 501 Hearing protection devices such as aviator helmet or ear plugs are required to be worn RADIOACTIVE MATERIALS Self luminous dials and ignition units may contain radioactive materials If such an instrument or unit is broken or becomes unsealed avoid personal contact Use forceps or gloves made of rubber or polyethylene to pick up contaminated material Place materials and gloves in a plastic bag Seal bag and dispose of it as radio active waste in accordance with AR 708 1 and TM 3 261 Refer to TB 43 0108 Repair shall conform to requirements in AR 385 11 SANDI NG DUST Sanding on reinforced laminated glass produces fine dust that may cause skin and lung irritations Observe necessary protective measures STARTING HELICOPTER Starting and operation of the helicopter will be performed only by authorized personnel TOXIC POI SONS Turbine fuels lubricating oils and adhesives contain additives which are poisonous and readily absorbed through the skin Do not allow them to remain on skin longer than necessary Wear protective equipment 55 1520 228 BD C1 CHANGE HEADQUARTERS DEPARTMENT OF THE ARMY NO 1 WASHINGTON D C 1 September 2005 TECHNICAL MANUAL OPERATORS AVIATION UNIT AND AVIATION INTERMEDIA
194. into a repair plan condition 3 no repair is required b Repair requirements including 2 If it is decided to restore Cleanup smoothing condition and the aircraft to condition 2 repair times should be recorded on DA Form 2404 a determine the required repairs for all damaged structured c If the worst case is better than elements that are below condition 2 condition 1 repair may be deferred except for cleanup and smoothing of all b Repairs on damaged struc rough edges The ends of all cracks tural elements that are better than must be stop drilled condition 2 may be deferred except for some cleanup and smoothing of the badly d If the worst case is between damaged areas condition 1 and 2 a decision must be made to degrade the aircraft to 3 If it is decided to restore condition 2 or to repair the aircraft the aircraft to condition 1 and restore it to condition 1 a determine the required 1 If the aircraft is degraded to repairs for all structural elements that condition 2 and is to perform a recovery below condition 1 flight severe damage should be cleaned up rough edges smoothed and cracks b Repairs on damaged struc stop drilled tural elements that are better than condition 1 may be deferred except for If it is decided to restore cleanup and smoothing the aircraft to condition 1 f Once all decisions are made and a a determine the required repair plan formulated complete repairs repairs for all dama
195. ir or evacuation To move by lifting pulling or pushing To restore a defective part component subassembl y assembly to a usable condition in accordance with the instructions contained in this manual or To supply an equivalent for To work over again The breaking of an airframe structural element or skin due to overstress hostile fire Very deep scratches caused by foreign particles between surfaces that are moving or between one moving and one stationary surface Scores follow the trave direction of the part Narrow shallow lines resulting from movement of foreign particles across a surface The non flight safety structural elements of an airframe The ability of the helicopter to fly at reduced airspeed and altitude from the battlefield or immediate vicinity to a maintenance collection point the main supply route Or maintenance activity for disposition repair or evacuation A structural design which relies on strength of the skin to carry a large portion of the load The skin is nor mally reinforced by longerons and vertical bulkheads walls but has no diagonal bracing leaving the interior basicly hollow The lubrication treating cleaning or preservation necessary to maintain the equipment and other respective parts in serviceable condition The aerodynamic exterior covering of the helicopter 6L05 7 55 1520 228 BD GLOSSARY SPALLING SPANWI SE SPAR STI FFENER STOP HOLE STRI
196. ir limits the capability of the aircraft the following entry will be made on DA Form 2408 13 a Place a circled red X in block 16 b State the limitation in block 17 1 6 Change 1 3 If the temporary repair requires an inspection at intervals list the required inspection on DA Form 2408 18 a Enter item to be inspected in block 5 b List the applicable TM in block 6 c State the frequency of the inspection in block 7 1 11 REPORTS All written reports required for BDAR fixes are found in DA PAM 738 751 If the helicopter can no longer fly the aircraft commander should immediately initiate an out of action report to his superior If com munications capability is damaged the aircraft commander should approach the nearest friendly radio and make his report if possible The report should include these essentials a Aircraft damage out of action or function partially impaired b Location of aircraft C Defense status d Mobility e Personnel report f Current and anticipated hostile action 9 Anticipated BDAR fixes and repair time TM 55 1520 228 BD GENERAL INFORMATION 1 DATE 2 MODEL SERIAL NO CREW CHIEF 5 6 PAGE NO 6a NO OF PAGES 3 STATUS TODAY AIRCRAFT 9 NEXT INSPECTION DUE H STARTS NO 1 NO 2 MEINE OTHER NGINE ENGINE a ELEC INTMED AIRCRAFT TRONIC MENT PREVIOUS
197. ixing Instruction for Sealant cartridges Rubber Repair Plug Assembly TEM Plug Modification for Three Plain Repair Du 0H 58 Flight Controls Schematic Collective Flight Control Cyclic Flight Control Flight Control Actuators Anti Torque Controls Sheet 1 of 2 Control Tube Dimensions Suggested Repair for Cont rol Rods or Tubes Control Rod with Bearing and Clevis Assemblies Flattened End of Fabricated Flight Control Corner Rounding on Fabricated Flight Control Bearing Assembly Connection of Fabricated Flight Engine System Control Bleed Air Heating and Ventilating System amp C Heating and Ventilating System Bleed Air A Mode Heating and Ventilating System Air Combustion Heater kx d Shroud Heater System Schematic Bleed Air Line Installation Bleed Line Patch Repair TEM Intercom System Sheet 1 of 2 UHF AM Communications System Sheet of 1 VHF AM Communications System and Connecting Cables VHF FM Communi cation System C Model Gyromagneti Compass Set AN ASN 43 and Connecting Cable Sheet 1 of 2 E Direction Finder Set AN ARN 89 Sheet 1 of 2 Radio Receiving Set AN ARN 123 V 1 Radar Altimeter System AN APN 209 2 Transponder IFF System AN APX 72 AN APX 100 Radar Warning System AN APR 39 LIST OF TABLES Title General Decision Logic General Assessment Table Tm Aircraft Structure Da
198. lace with good defective and replaced relay salvaged from non flyable aircraft Or a nonessential circuit OPTION 1 Salvaged Power Relay Replacement b Second option Jumper across power terminal and bus bar terminal NOTE studs located on relay case To check power relay for malfunction locate ter Identical part number Figures minals and X2 on the relay With a 11 42 denotes interchangeability multimeter set on the 0 50 V dc scale damage is extensive salvaged check the voltage from terminals Xl and relays may be difficult to attach X2 to the aircraft fuselage ground to bulkheads Figure 11 41 One of the two terminals should have 24 28 V dc on it when the power relay control circuit is energized No dc voltage indicates teno Al A2 Don diens 1 A2 1 2 a Wil TYPE A GND GND i TYPE B Figure 11 41 Block Diagram Power Relay Check and Test 11 41 TM 55 1520 228 BD ELECTRICAL AND AVIONICS SYSTEM LI MI TATIONS PERSONNEL TI ME Soldier 30 Minutes MATERIALS TOOLS REQUIRED Salvaged Power Relay None REQUI RED PROCEDURAL STEPS L Obtain salvaged power relay 2 Disconnect battery 3 Remove damaged power relay as follows NOTE Note the position of wires bus bar and what terminals they are con nected to a Remove attaching hardware wires and bus bar b Remove attachment bolt and lift relay free from compartment 4 Position salva
199. ldier 20 Minutes MATERI 15 TOOLS REQUIRED Salvaged Circuit Breaker Electrical Tape item 49 Appx PROCEDURAL STEPS l Gain access to area behind circuit breaker panel Figure 11 35 by turning duze fasteners counterclockwise 2 Remove screws holding plastic face plate on circuit breaker panel 3 Use pliers to remove nut and inside star lock washer from damaged circuit breaker 4 Use phillips screw driver to remove the two screws from the back of the circuit breaker 5 Replace bad circuit breaker with the salvaged circuit breaker TM 55 1520 228 BD ELECTRICAL AND AVIONICS SYSTEM 6 Connect back of circuit breaker to line and bus bar by reinstalling the two phillips screws Place inside star washer and nut on front of circuit breaker and tighten with pliers e on front Replace plastic face plat ith screws of circuit breaker panel w previously removed Clean and remove any debris from inside circuit breaker panel and close panel Secure by turning duze fasteners clockwise OPTION 2 Individual Strands of No 38 AWG as Circuit Breaker BDAR Repair LIMITATIONS Emergency repair PERSONNEL TIME REQUIRED 1 Soldier 20 Minutes MATERI ALS TOOLS REQUIRED 1 Foot of No 38 AWG Wire PROCEDURAL STEPS 1 Perform steps 1 thru 4 of option 1 2 Identify the wires hooked to each circult breaker Typical circuit breaker is shown in Figure 11 36 3 Determine amperage of damaged circuit
200. le 13 1 I NO REPAIR Flight DAMAGE WITHIN ACCEPTABLE IS REPAIR REPLACEMENT Control FEASIBLE YES REPAIR REPLACE TUBES FLIGHT CONTROL PER SEC II NCTIONAL CHECK FOR PRIOR OPERATION AND SAFETY System Assessment IMITS RENDER SYSTEM SAFE AND DETERMINE RESTRICTIONS RECOVER CANNIBALIZE DESTROY TM 55 1520 228 BD FLIGHT CONTROLS SYSTEM Procedures 55 1520 228 BD FLIGHT CONTROLS SYSTEM copilot s and pilot s cyclic collec tive and tail rotor controls to the a flight control TD See Figure iior a schematic a schematic of the system TE refer to Figures 13 2 thru 13 n complete detail on each individ system and Sie hate afr we Table 13 2 D 7 of tubes Ma di mensions repairs on all flight tubes using one of the two options provided in this section Insure that splice repairs option 1 do not cause any interference at bulkhead lighting holes or adjacent components OPTION 1 Tubes Control LIMITATIONS flight PERSONNEL TI ME e 1 Soldier e 2 Hours MATERI ALS TOOLS e Metal Sleeve e Angle Stock e 80115 PROCEDURAL STEPS L Put aircraft flight into neutral rig Splicing Flight Inspect after every REQUI RED REQUI RED control system 2 Disconnect control tube and remove damaged from aircraft 3 Trim damaged area 4 Using Table 13 2 and Figures 13 2 thru 13 5 select a metal spl
201. lectrically grounded when parked to dissipate static electricity Turn off all power switches before making electrical connections or disconnections HIGH PRESSURE Extremely high pressure can occur during and after operation of certain equipment If this pressure is not relieved before working on this equipment serious injury or death may occur Be sure to open all drains and vents before beginning disassembly HYDRAULIC FLUID Prolonged contact with liquid or mist can irritate eyes and skin Wear rubber gloves when handling liquid After contact with skin inmmediately wash contacted area with soap and water If liquid contacts eyes flush immediately with clear water If liquid is swallowed do not induce vomiting get immediate medical atten tion If prolonged exposure with mist is likely wear an appropriate respirator When fluid is decomposed by heating toxic gases are released TM 55 1520 228 BD LIFTING Lifting or moving heavy equipment incorrectly can cause serious injury Do not try to lift or move more than 50 pounds by yourself Bend legs while lifting Do not support heavy weight with your back Always use assistants during lifting opera tions Use guide ropes to move hanging assemblies Lack of attention or being in an improper position during lifting operations can result in serious injury close attention to movements of assemblies being lifted Do not stand under lifted assembly or in a position where you could be p
202. leted or 4 f any leakage is incurred due to the above procedure and cannot be corrected or if time constraints take precedent the system may be bypassed as a last resort refer to option 2 OPTION 2 Bypass Entire System LIMITATIONS Erratic flight control NOTE The pilot must be made aware that any fuel demand he places on the engine will be reacted upon i mme diately leading to quick engine response and erratic flight control 6 6 PERSONNEL TIME REQUIRED Soldier 15 Minutes MATERIALS TOOLS REQUIRED Flex Line Tubing 10 0 25 in Length 12 in rein No 4 Fittings l Refer tol Figure 630b to establish bypass configuration 2 Disconnect clamp from flexible hose and extend flexible hose to rigid hose 4 Use fitting from either hose and connect the two hoses 4 Insure both o rings are reusable and no leakage exists If either o ring is damaged scavenge from bypassed compo nents 6 7 011 TANK PUNCTURED GENERAL INFORMATI ON seize in a matter of minutes if run without 011 This procedure lists six methods to fix a leaking oil tank depending on the size of the leak and the materials available If fuel cel repair kit is avallable utilize its contents The engine wil LIMITATIONS None NOTE Some repairs may come loose due to heat and vibration OPTION 1 Wood Plug for Smooth Round Holes PERSONNEL TIME REQUIRED 1 Soldier 30 Mi nutes MATERI ALS TOOLS REQUIRED Plug Wo
203. lve Fuel Filter Heat er Combustion Blower Air Scoop Igniter Plug Duct Firewall Shut Off Control Temperature Control Pilot Seat Back Copilot Seat Back j 4 di 6 1 1 Figure 15 4 Combustion Heater TM 55 1520 228 BD ENVIRONMENTAL CONTROL SYSTEM L Blower Defogger Distribution Valves 2 Air Mixing Valve 1 Cockpit Distribution Valves 3 Firewall Shut Off Valve 8 Cabin Distribution Valves 4 Nr Mixing Valve Control 9 Fan Air Intake 5 Firewall Shut Off Valve 10 Cold Air Intake Control 11 Shroud Assembly 15 6 Figure 15 5 Shroud Heater System Schematic 55 1520 228 BD ENVIRONMENTAL CONTROL SYSTEM Table 15 1 Assessment Procedures ENVIRONMENTAL CONTROL SYSTEM SUSTAINS BATTLE DAMAGE VISUALLY INSPECT DAMAGE DEFERRABLE2 5 DEFERRABLE FUNCTIONAL CHECK FOR PROPER OPERATION IS DAMAGE NO REPAIRABLE AIRCRAFT MAY FLY WITH SYSTEM INOPERABLE RECORD ON 2408 13 YES REPAIR RIGID DUCT PER SEC II REPAIR FLEXIBLE DUCTS PER SEC II REPAIR AIR BLEED LINES PER SEC II TM 55 1520 228 BD ENVI RONMENTAL CONTROL SYSTEM PROCEDURAL STEPS 1 Locate damaged area and remove panels and or other items as necessary to gain access to the duct to be repaired Refer th Figures 15 2 and 15 3 for locations of rigid plastic ducts 2 Cut a patch out of sheet stock 4 Tape into place 4 Record BDAR action taken When mssion is complete as soon as p
204. m the tube end Flush with any available fluid or if end connections are inacces sible momentary activation of the system will suffice 9 7 ALUMINUM TUBING DAMAGE GENERAL INFORMATION Aluminum tubing is Subject to damage by projectiles and fragments Replacement with original replacement parts is desirable but not essential In BDAR tubing and hose and MS fittings and other similar com ponents can be substituted one for the other Available time tools skills and materials will determine which repair option to use Whenever an alu minum line has complex bends replace ment of the damaged section with hose option 3 is probably the quickest fix OPTION 1 In Line Repair LIMITATIONS None PERSONNEL TI ME 9 Soldier 30 Minutes REQUI RED MATERI ALS TOOLS e 2 MS Unions Splice Tube Tubing Cutter Knife or File 4 MS Fittings REQUI RED PROCEDURAL STEPS 1 Cut and remove damaged section of tubing Figure 9 7 Tube ends must be square 2 Clean ends of knife or file undamaged tubing with 3 Measure the distance between the two undamaged ends and prepare a tube splice replacement section of this size Clean ends of splice section as done in step 2 4 Install an MS fitting on each end of the splice tube Figure 9 8 5 Insert the splice tube and tighten all fittings Figure 9 9 6 Record BDAR action taken mission is complete as soon as practical repair the equipmen
205. mage Assessment Procedures Damage Limits Forward Fuselage Condition Damage Limits Aft Fuselage Condition Damage Limits Tail Boom and Landing Gear Damage Limits Forward Fuselage Condition Condition 11 Table No 55 1520 228 BD LIST OF TABLES Cont Title Damage Limits Aft Fuselage Condition 11 Damage Limits Tail Boom and Landing Gear Metal Substitution Chart Pea Assessment Procedure Logic Engine BDAR Assessment Logic Assessment Procedures m Drive Train System BDAR Assessment Procedures Assessment Logic Seals Reference and Temperature Guides Chart Electrical and Avionics Assessment Logic Function and Designation Letters Unshielded Crimp Splice ey Wire Repair Segments Shielded Cable Repair Terminal Lugs Fuse Link Strands Fuel System Assessment Procedures Condition 11 Flight Control System Assessment Procedures Nominal Tube Splice Sizes Bol t Dri Sizes for Cont rol Tube Repairs Assessment Procedures Essentia Spare Parts Spare and Repair Parts Weapons I Substitute Fuels for 4 Fuel Fuels for the 0H 58 Helicopter Substitute Commercial Fuels Alternate and Expedient Fuel Blends Wire Table Intercom System Wiring Table UHF AM Communication System Wiring Tabl e VHF AM Communication System Wiring Table VHF FM Communication System Wiring Table Gyromagnetic Compass Set Wiring Table ADF AN APN 89 Radio Rec
206. mage recording for 1 Other damages to the same element 2 Other damaged elements in the same subassembly 3 Other damaged sub assemblies in the section of the airframe 4 Other damage sections of the airframe as required f After the damage inspection is completed file the damage report in the aircraft log book and make entries as required 2 Damage diagrams Show the location and extent of damage as shown in the diagrams in Figure 1 3 The damage can be drawn by hand Accurately locating damage on a diagram will greatly help the damage assessment procedure 4 5 55 1520 228 BD ATRFRAMI 4 6 EQUIPMENT INSPECTION MAINTENANCE WORKSHEET Por uae of thts term 18 730 the proponent egency is the Office of rhe Denury Chief of Staff tor Logistics NOMENCLATURE MOORL APPLICABLE AEPERENCE COLUMN a Enter TM item number COLUMN b Enter the applicable condition status symbol COLUMN c Enter deficiencies and shortcomings COLUMN d Show corrective setion for deficieney or shortcoming listed in Columa c OO kasi o fe nsn COLUMN s Individual ascertaining compieted corrective action initial this columa STATUS SYMBOLS X Indiestes a deficiency in the equipment that places DIAGONAL Indicates a materiel defect other in an inoperable status than deficleney which must be corrected to i
207. mal oil pressure temperature 10 discharge the high pressure air in readings or warning lights order to alleviate the stall condition The bleed valve is initially in the open b Abnormal noises or high frequency position and senses pressures between vibrations the fifth stage and the scroll Once the stall region 15 overcome usually c Sudden loss of power between 65 percent to 75 percent N1 and scroll pressure is reached the valve is closed Should the valve not close correctly excess air will be dumped at the compressor and the required burner pressure will not be obtained resulting in engine abort TM 55 1520 228 BD POWER PLANT Figure 6 1 T63 Series Engine POWER PLANT Table 6 1 Engine BDAR Assessment Logic JUMP START BATTERY NO USING 24 28 VDC EXTERNAL SOURCE TRUCK TANK A C ENGINE SUSTAINS DAMAGE HECK ALL FUEL LINES AND FILTERS FIX LINES PER CHPT 9 VISUALLY INSPECT DAMAGE REPLACE DEFECTIVE NO IGNITION EXITOR IS IGNITION AUDIBLE IS DAMAGE DEFERRABLE REFER TO STANDARD TROUBLESHOOTING PROCEDURES NO REPAIRS NECESSARY START ENGINE DAMAGE REPAIRABLE EVACUATE CANNIBALIZE DESTROY HECK AIRBLEED AND DRAIN VALVE PER IS TOT HIGH YES REFER TO STANDARD TROUBLESHOOTING PROCEDURES P ATD AND DOUBLE CHECK VALVE REPAIR LINES PER CHPT 9 AND VALVE PER SEC II PR INADEQUATE
208. metal for another riding consideration on the battlefield Alternate repair materials can be BDAR airframe repairs are usually per obtained from scrapped aircraft It is formed on the outside of the aircraft to also permissible to fabricate from save the time required to gain access to thinner gauge material and use multiple the interior lf however access to the thickness interior damaged structure is already ae inside BDAR repairs may be made 55 1520 228 BD AIRFRAME TM Substitution Chart Metal Table 4 8 uv Stainless Titanium Steel 4130 8630 D 7075 1025 2024 s ef of af sl oP ef A of 5 of ol 2 mt a kam Kami Gami Laal Lami kas Kas nm e 154b eae fafa mim cc ici lt lt lt 4 of of of of af of of uni Gani Kami mie Laa Lami Kami Laal taml ioc ef of of of of of of of of of of of of of of ol of of of of of r lasal Kasni kamal Kami Kami Lami lami Kami a a fed ala st yun Slope oye Sc ciciic cici cic ci c clcjc cidolala of of 45 15 of of of of of of of of of of of dem Lami Kani Cam Kena Kami am Kam Kanal Kami anl Kami a tt
209. n CIRCLED X indicates a deficiency however the equip ee et pale the iom completsiy ment may be operated under specific limitations directed by higher authority or as prescribed locally LAST NAME INITIAL IN BLACK BLUE BLACK INK until corrective action can be accomplished OR PENCIL Indicates that a completely aatisfactory HORIZONTAL DASH indicates that a required inspee condition exiata thon component replacement maintenance operstion check or test flight ia due but has not been accomplished or overdue MWO has not been accomplished ALL INSPECTIONS AND EQUIPMENT CONDITIONS RECORDED ON THIS FORM HAVE BEEN DETERMINED IN ACCORDANCE WITH DIAGNOSTIC PROCEDURES AND STANDARDS IN THE TM CITED HEREON Person iy performing inspection SIGNATUAE Maintenance Supervisor FOR AIRCRAFT Status aymbois will be recorded in red OMANHOUR AgGUIASO CORRECTIVE ACTION FORM Reo edition ef 1 Jan 84 ich wii be used DA 2404 Figure 4 2 DA Form 2404 55 1520 228 BD ATRFRAME 3 Marking damage Mark the CD is the depth of the damage into the damaged structure using grease pencil or flattened cross section The length of paint Use the labeling scheme shown in the remaining effective cross section Figure 1 3 is still capable of supporting a load All dimensions are in inches CAUTION CS atb
210. na lug Secure both ends of the insulation with tie wraps or string ties as shown 11 7 8 If a section of wire needs to be replaced a double repair can be made to bridge the ends of the original wire back together Figure 11 8 9 Record BDAR action taken mission is complete as soon as practical repair the equipment system using standard maintenance procedures When OPTION 7 Metal Clamp Method LI MI TATI ONS This is an emergency type repair PERSONNEL TI ME e 1 Soldier 10 Minutes REQUI RED MATERI 15 TOOLS REQUIRED e Screw Clamp Control Cable Clamp or Safety Wire item 26 Appx C e Insulating Sleeve or Electrical Tape item 49 C e Knife e Cable Ties item 10 Appx PROCEDURAL STEPS l Cut ties and work broken wire to the outside of the bundle 25 Pull sufficient slack from the wire run toward the break so that there wil be no strain on the splice 2 Wipe wire clean with a clean dry rag or a rag dampened with 1 1 1 tri chloroethane alcohol or equivalent 4 Trim broken ends of wire 5 Remove 2 inches of wire insulation from each end of the damaged wire 11 13 TM 55 1520 228 BD ELECTRICAL AND AVIONICS SYSTEM SCREW OR BOLT 3 4 6 Ramor push the two wi that the strand 1 Secure wit safety wire 0 8 Insulate wi 9 Record BD complete as 5 procedures 11 14 s interlink h screw cla other suita
211. nibalization or destruction 4 6 DETAIL ASSESSMENT a Access to Damaged Structure Locate all damage to airframe primary Structure Remove access panels covers and fairings in the damaged area Remove aircraft components as required to inspect the structure Use the location of entrance and exit wounds and the estimates of projectile paths to determine the areas where damage may be present and access to interior inspec tion will be needed If an area of structure suspected of being damaged cannot be reached by other means cut small inspection holes in the exterior Skin Then inspect internal members with an inspection light and mirror b Inspecting for Cracks 1 Inspect for cracks caused by impact or penetration in regions away from the site of primary damage 4 4 2 Inspect for small and large cracks caused by projectile damage Small cracks will enlarge under con tinued loading particularly when located at the edge of a hole 3 Locate cracks in primary structure using magnifying glass or dye penetrant Check for cracks around fasteners in areas showing signs of overstress 4 Inspect for cracks in all areas of an explosion caused by a high explosive incendiary HEI strike c Inspecting for Structural Changes 1 Inspect damaged area and urrounding undamaged area for evidence f buckling crippling and misalign ent Kinks wrinkles and sheared ulled through or missing fas
212. nitial circle amp 9 amp 9 TO INDICATE REPAIR INSTRUCTIONS For internal damage draw a dashed jo ON REPAIR circle around the repair instructions INSTRUCTIONS INSTRUCTIONS For external damage write repair REPAIR instructions but do NOT enclose INSTRUCTIONS PARTIAL with a circle Figure 1 3 Damage Assessment Markings Sheet 1 of 3 1 9 55 1520 228 BD GENERAL INFORMATION WRITTEN INSTRUCTIONS MEANING See me print name amp See assessor or whoever has signed written instructions rank Signature for additional information Names of parts to Where compound damage occurs the names or abbreviations be repaired item of specific items can be written adjacent to the damage Skin stringer to clarify repair instructions Full A full strength repair is required Partial Partial strength repair required in accordance with specific aircraft BDAR manual OK No repairs required damage is within acceptable limits for battle conditions Continual assessment or reinspection is required after each sortie Instruction markings for system are in two parts 1 Repair instruction markings and meanings are shown on this sheet and are used to indicate repair actions required 2 System Identification When known identify the system using markings shown on sheet 3 of this figure MARKINGS MEANING Fix Repair the damaged system in accordance with approved standard BDAR technique
213. nner lines 3 Abrade the inner lines or inner surface at least 1 2 inch beyond the enlarged hole preferably more if con ditions permit Abrade the outer sur face to a minimum of 4 inches from the enlarged area NOTE If the fraying fibers are too numerous trimthe fiber with scissors 4 Clean the abraded areas using towels soaked in solvent 5 Cut a fabric patch 4 inches in diameter or large enough to extend at least 1 inch beyond the damaged area and add a 1 2 inch hole in the center Soak the patch in solvent 6 the adhesive per option 2 instructions step 5 and extrude into a plastic cup NOTE Adhesive can be used between 20 through 120 but must be warmed to room temperature prior to mixing and be mixed at room temperature Pot life of adhesive is approximately 25 minutes at 70 F Apply adhesive to inner liner using finger to swab cement around the wound Apply adhesive to concave surface of the rubber plug this is the surface the cord is attached to Refer to Figure 112 4 for rubber plug assembly NOTE Use adhesive as required retain some for finishing the outside of the cell repair Fold the rubber plug and insert it through the hole in the cell NOTE Retain cord to prevent loss of plug in the cell enlarge the 9 Pull the plug into position and rotate it in position to smooth out the adhesive interface Center the plug on the wound 10 Apply a layer of adhesive 4
214. nsuming part of are added to the identification code electrical and avionics battle damage AL Alumel CR Chromel FE Iron assessment is wire identification CN Constantan and CU Copper Added and repaired wiring should be identified to aid in troubleshooting c Deferral Repair of systems and f time permits tape or sleeving at Subsystems which have adequate redun each end of added wiring of a material dancy or are not critical to mission Suitable for the ambient temperature accomplishment may be deferred if safety range may be used Typical wire and of flight is not significantly degraded circuit identification schemes are shown Requirements must be examined to deter in Figure 11 1 and mine if relaxed criteria for repair and Appendix F llists and depicts the major aircraft performance can be accepted components cable routes and wiring The commander may defer combat main terminations for the more compl tenance and battle damage repair even avionics systems if doing so places operational limita tions on the aircraft b Circuit Function The unit number and circuit designation letter identify the type of circuits The wire number consists of one or more digits 55 1520 228 80 ELECTRICAL AND AVIONICS SYSTEM Table 11 1 Electrical and Avionics Assessment Logic IDENTIFY DAMAGED SYSTEM ARE DAMAGED SYSTEM PRESENT i NO IS REPAIR REPLACEMENT FEASIBLE YES NO RECOVER CANNIBALIZE DESTROY
215. ny remaining cracks Figure 4 19 4 17 SKIN WEB DOUBLER DAMAGE 2 Cut and fit a patch plate one gauge thicker and of the same material GENERAL INFORMATION Much of the as the damaged structure The plate fuselage construction is relatively thickness should be based on the thick light built up structure Small est part of the damaged area The patch damage will likely exceed the plate should be large enough to allow allowable limits and will require installation of the required fasteners repair A patch plate can often be on all sides Cut and fit shims to fil used to repair the damage gaps LIMITATIONS None Condition 1 Inspect after every flight for damage growth TM 55 1520 228 BD RFRAME PATCH PLATE 4 14 1 4 1 r r Figure 4 19 6 FASTENERS MIN IN MAJOR CAPS EXTRUSIONS ETC 2D MIN EDGE DISTANCE 4D 6D SPACING 4 4 4 SECTION A A Typical Patch Plate Repair 3 Install a minimum of six rivets in each row on each damaged end of major structure such as caps extrusions etc Remove existing rivets and back dril holes in the patch plate if the area is accessible If back drilling is not practical it may be possible to interpitch new rivets between existing rivets Use same size rivets or Oversize rivets if necessary 4 Install two rows of ri
216. o TabTe IT 5 Figure 11 26 Coax Splice Preparation 11 29 55 1520 228 BD ELECTRICAL AND AVIONICS SYSTEM 2 Slide the shield sleeve and inner sleeve onto one of the coaxial cables in the order given 3 Splice the center conductor Use the red cavity of the crimp tool 4 Shrink the inner sleeve over the splice Figure 11 27 Use reflector temperature set at 900 F Keep the hot air away from shield sleeve 5 Center and shrink the shield sleeve over the splice area so that the solder melts and flows Shield Sleeve braid must overlap coax braid at both ends Use reflector temperature set at 900 F 6 Record BDAR action taken When mission is complete as soon as practical repair the equi pment system using standard maintenance procedures 11 16 RG 124 0 COAX SPLICE FOR RG 180B U RG 142B U RG 302 U 6 303 0 GENERAL INFORMATION There are various coax splices in the wiring repair kit that may be used for the different types and sizes of coaxial cable LIMITATIONS This is a temporary repair PERSONNEL TI ME e 1 Soldier e 15 Minutes REQUI RED MATERI ALS TOOLS REQUIRED e Crimp Tool AD 1377 item 10 Appx 8 Coax Splice item 10 Appx B Stripper or Knife Reflector item 10 Appx Heat Gun Heat Source item 10 Appx B PROCEDURAL STEPS 1 Prepare coax cable Figure 11 26 Refer to Table II 5 11 30 2 Slide shield sleeve inner sleeve and filler sleeve onto
217. oden Hose or Tubing TM 55 1520 228 BD POWER PLANT DOUBLE CHECK VALVE e 7 Grog 9 8 e e 9 FLEXIBLE HOSE E ACCUMULATOR ACCUMULATOR Vu FLEXIBLE HOSE a SYSTEM INTACT b BYPASS ENTIRE SYSTEM DOUBLE CHECK VALVE DOUBLE CHECK VALVE es e 9 Geo i 5 ee ACCUMULATOR HOSE FLEXIBLE HOSE ACCUMULATOR Pegs ay REMOVE ONE ACCUMULATOR d REMOVE ONE ACCUMULATOR ACCUMULATOR 5 9 ACCUMULATOR iy HOSE FLEXIBLE HOSE 67 ACCUMULATOR Bees e REMOVE DOUBLE CHECK VALVE f REMOVE DOUBLE CHECK VALVE Figure 6 3 Double Check Valve System Possible Alternatives 5 1 TM 55 1520 228 BD POWER PLANT PROCEDURAL STEPS L Obtain a small piece of hose or tubing and insert the piece into the hole on the oil atk Ue 6 2 Insert a tapered wooden plug inside the hose or tubing wooden plug should be checked periodically and retightened if necessary 3 Replenish oil supply 4 Record BDAR action taken When mission is complete as Soon as practical repair the equi pment system Using standard maintenance procedures OIL TANK WALL N RUBBER TUBING Figure 6 4 OPTION 2 PERSONNEL TI ME 1 Soldier 30 Mi nutes Wood Plug Duct Tape for thin cracks REQUI RED 6 8 MATERIALS TOOLS REQUIRED Tape Fiberglass or Duct item JG Solvent Naptha item 7 Appx C or Equivalent PROCEDURAL STEPS l Clean area aroun
218. of accidental firing Personnel shall remain clear of hazardous area CLEANING SOLVENTS Cleaning solvents may be flammable and toxic Use only in well ventilated areas Avoid inhalation of vapor and skin contact Do not use solvents near open flame or in areas where very high temperatures prevail Solvent flash point must not be less than 100 F COMPRESSED AIR Compressed air can blow dust into eyes Wear eye protection Do not exceed 30 psig air pressure ELECTROLYTE Battery Electrolyte Potassium Hydroxide is corrosive Wear rubber gloves apron and face shield when handling leaking batteries If potassium hydroxide is spilled on clothing or other material wash immediately with clean water If spilled on personnel immediately start flushing the affected area with clean water Continue washing until medical assistance arrives 355 1520 228 BD HIGH VOLTAGE is used in this equipment DEATH ON CONTACT may result if personnel fail to observe safety precautions Never work on electronic equipment unless there is another person nearby who is familiar with the operation and hazards of the equipment and who is competent in administering first aid When the technician is aided by operators he must warn them about dangerous areas Whenever the nature of the operation permits keep one hand away from the equi pment as to reduce the hazard of current flowing through vital organs of the body Do not be mislead by the term
219. of the fix any one of these metals could be used Likewise any one of the rivets items 98 thru 115 may be used to attach the patch plate depending on the application b One of the key points concerning successful BDAR repairs is flexibility The users of this manual should strive to use the items on hand provided a safe repair is made The stringent requirements of normal maintenance may be lifted ix x Blank 55 1520 228 BD CHAPTER 1 GENERAL INFORMATION BDAR FIXES SHALL BE USED ONLY IN COMBAT OR FOR TRAINING AT THE DISCRETION OF THE COMMANDER AUTHORIZED TRAINING FIXES ARE LISTED IN APPENDIX E IN EITHER CASE DAMAGES SHALL BE REPAIRED BY STANDARD PROCEDURES AS SOON AS PRACTICABLE Section I 1 1 PURPOSE The purpose of Battle Damage Assessment and Repair BDAR is to quickly return the disabled heli copter to the operational commander by expediently fixing bypassing or jury rigging components to restore the mini mum essential systems required for the support of the specific combat mission for self recovery These repairs will be temporary and may not restore full performance capability Standard repair will be completed as soon as practical 1 2 SCOPE a This technical manual des cribes BDAR procedures applicable to 58 helicopter series and these procedures are to be used by crew operators aviation unit maintenance AVUM teams and aviation intermediate maintenan
220. olts 1 Remove damaged control rod from de ice valve and control actuator If extremely PROCEDURAL STEPS cold weather secure de ice valve control lever in open position by tying the lever 1l Drill hole on end of control rod to an adjacent part of the engine nose Insure that original length of damaged area If hot weather secure valve in rod is known Cut substitute tube to closed position with safety wire proper length and drill hole on other end Install substitute tube and secure 2 Record BDAR action taken When with screw or bolts and nuts mission is complete as soon as practical repair the equi pment system using standard maintenance procedures 14 1 55 1520 228 BD UTILITY SYSTEMS DE ICE VALVE DE ICING CONTROL CONTROL ROD Figure 14 1 Engine De lce System 14 2 TM 55 1520 228 BD CHAPTER 15 ENVIRONMENTAL CONTROL SYSTEM BDAR FIXES SHALL BE USED ONLY IN COMBAT OR FOR TRAINING AT THE DISCRETION OF THE COMMANDER AUTHORIZED TRAINING FIXES ARE LISTED IN APPENDIX E IN EITHER CASE DAMAGES SHALL BE REPAIRED BY STANDARD PROCEDURES AS SOON AS PRACTICABLE Section 1 INTRODUCTION 15 1 SCOPE This chapter contains c The shroud heater system utilizes BDAR procedures for the heat and vent a carbon monoxide CO indicator located bleed air and defogging systems The at the instrument panel in full view of 0H 58A C has one of three types of heat the pilot systems bleed air Figures 15 1 15
221. on Terminal Lug Repair Ram Wire Repair TEE Heat Shrinkable Tape Insulation Repair with Sleeving Shielded Cable Repair Preparation Shielded Cable Splice Shielded Cable Spliced Shielded Cable Repair Pigtail Method Repair Substitute Shielded Braid Repair Shield Terminator Repair Preparation Shield Terminator Repair 62 8 de Nickel Plated Shield Terminator Preparation Nickel Plated Shield Terminator Repair Terminal Lug Repair ko Eh Self Clinching Cable Strap Self Clinching Cable Strap and Tool Tie Tape Repair Procedure Coax Splice Preparation Coax Splice Inner Sleeve Coax Splice Shield Sleeve Coax Splice with Tubing Sleeve Coax Splice with Cable Braid over Barrier Sleeves Coax Repair with Cable Braid over Barrier Sleeve Component Bypass Connector Pin and Socket Damaged Connector and Pigtail Circuit Breakers E Typical Circuit Breaker Connection Construction of Fuse Link Splicing Bus Bars Lengthening Bus Bars Battery Storage BB 476 A Cell Layout Block Diagram Power Relay Check and Test Location of Power Relays Block Diagram Typical Power Rel ays Jumper Wire Fabrication Frequency vs Wave length TM 55 1520 228 BD 55 1520 228 80 LIST OF ILLUSTRATIONS Cont Figure Title Preparation of Coax Installation of Field Expedient Antenna 0H 58 Fuel System n Emergency Mechanical Cl amp Repair M
222. on as TERMINAL WIRE practical repair the equipment system DETAIL A DETAIL B using standard maintenance procedures 11 13 TERMINAL LUGS GENERAL INFORMATION Terminal lugs are provided in the wiring kit Table 11 6 The general procedure for installing terminal lugs is as follows LIMITATIONS None PERSONNEL TIME REQUIRED 1 Soldier e 10 Minutes Per Wire DETAIL C Figure 11 22 Terminal Lug Repair 11 26 5 Locate terminal with locator detai B Terminal should locate with flange over the top of the locator 6 Insert wire to proper depth 7 Close handle of tool until dies are closed and ratchet releases The cri mp is now complete see detail C 8 Record BDAR action taken When mission is complete as soon as practical repair the equipment system using standard maintenance procedures 11 14 WIRE BUNDLE TIE WRAPS GENERAL INFORMATI ON repairs are made insure minimum essen tial cable clamps lugged bundle ties and unlugged wire bundle ties are replaced After wire damage TM 55 1520 228 BD ELECTRICAL AND AVIONICS SYSTEM OPTION 1 Self Clinching Cable Straps LIMITATIONS These straps are not to be used under the following conditions temperature environments which exceed 85 C 185 F On coaxial cables or bundles con taining coaxial cables which do not have hard dielectrics e n areas where excess material from Strap cuttings or failure of the mounted strap wo
223. on features and may be of the same size they are not necessarily interchangeable able 9 2 relationship and 528775 and gaskets in are as follows di mensi onal between AN6227 AN6230 series o ring packings the various sizes AN6227 B1 through B7 are equi valent to MS28775 006 through 012 186227 88 through B14 are equivalent to MS28775 110 through 116 9 AN6227 B15 through 827 are equivalent to MS28775 210 through 222 N6227 B28 through B52 are equi valent to MS28775 325 through 349 AN6227 B53 through B87 are equi valent to MS28775 426 through 460 9486227888 is equivalent to MS28775 425 AN6230 B1 through B25 are equivalent to MS28775 223 through 247 9 10 HYDRAULIC FLUID SUBSTITUTIONS a If the original specified fluid is lost and standard replacement is not available a substitute fluid must be used Check Appendix D for a compatible fluid If a compatible fluid is not available any available nonflammable lubricant can be used in a BDAR action as a last resort CAUTION O rings wipers plastic or rubber draulic system may and for that ability of gaskets or other parts of the hy swell or shrink reason continued oper the system cannot be guaranteed Following such a sub stitution instructions for bringing the system back to normal should include checking all moving parts of the hydraulic system and al hydraulic activated devices for proper operation
224. onal thin sheet metal structure composed of longerons and bulkhead frames as beam elements and decks and skins as shear panels Some of the fairing and decks are honeycomb panels d The tail boom is a circular sec tion with a horizontal stabilizer ver tical fin and anti torque rotor attached The tail boom is a full mono coque structure utilizing a tapered cir cular section of aluminum alloy skin Redistribution in the forward end which is required to transfer loads from the 4 16 monocoque structure to the four attach ment fittings on the fuselage 15 accomplished by the use of intercoastals and two aluminum redistribution bulkheads The horizontal stabilizer is a standard spar rib skin riveted construction The vertical fin is of standard sandwich construction using aluminum honeycomb core and thin aluminum skins The upper half of the upper fin is composed of fiberglass skins and honeycomb core e The damage assessment procedure described in paragraph 4 5 consists of damage measurement determination of the corresponding allowable damage limit and associated condition and formulating repair instructions This data is recorded on DA Form 2404 4 12 DAMAGE MEASUREMENT a Refer to Figures 4 8 thru 4 15 for location and identification of major fuselage and tail boom structural areas b Refer pu for each damaged element measure the depth CD and the length width CL or WL 0f each dama
225. one of the coaxial cables in the given order 3 Splice the center conductor Use the red cavity of the crimp tool 4 Shrink the filler sleeve over the splice Use reflector temperature set at 900 F Keep hot air away frominner and shield sleeves 5 Shrink the inner sleeve over the splice Figure 11 27 Use same reflector and temperature Keep hot air away from shield sleeve 6 Center and shrink the shield sleeve over the splice area so that the solder melts and flows Figure 11 28 Shield Sleeve braid must overlap coax braid at both ends Use same reflector and tem perature 1 Record BDAR action taken When mission is complete as soon as practical repair the equi pment system using standard maintenance procedures 11 17 RG 214 0 COAX SPLICE FOR RG 9B U RG 225 U RG 393 U GENERAL INFORMATION There are various coax splices in the wiring repair kit that may be used for the different types and sizes of coax cable LIMITATIONS This is a temporary repair PERSONNEL TI ME 1 Soldier 15 Minutes REQUI RED MATERI ALS TOOLS REQUIRED e Crimp Tool item 10 Appx Coax Splice item 10 Appx B Stripper or Knife Reflector item 10 Appx B Heat Gun Heat Source item 10 Appx B TM 55 1520 n 228 BD ELECTRICAL AND AVIONICS SYSTEM INNER SLEEVE CENTER OVER SPLICE Figure 11 27 SHIELD OVERLAP SHIELD SLEEVE Figure 11 28 PROCEDURAL STEPS 1 Prepare coax cable Re
226. oom Intercoastals D Nxc D NxW No Damage Allowed No Damage Allowed 182 40 BS164 10 Gearbox Mounting Skin At Any Circumference No Damage Allowed i Bulkheads 1 00 2 5 si Damage Allowed Driveshaft Support Spar 1150 3 00 5 kc Honeycomb Panels 5 pud EE 2 1 Fin to Antenna 1 No Damage Within 3 of Inserts Tail Skid Tube Fitting No Damage Restrictions Landing Gear Skid Tube E Fwd amp Cross qq qug ee 3mNvadaiv 9 8 0 0 91 99 WL TM 55 1520 228 BD Al RFRAME 5 There are large holes or cracks in an area of the door or hatch exposed to the windstream and peeling 07 tearing of the material in flight is probable 6 Fasteners holding major com ponents of the hatch door or door jamb together are sheared pulled through or missing at three or more adjoining locations 7 More than 20 percent of the total number of fasteners are similarly damaged k Evaluation of Damage to Fairings and Cowlings Classify a damaged fairing or cowling as failed if any of the following conditions exist 1 Damage to the fairing and cowling or its attaching structure pre vents it from being adequately secured to the airframe 2 The fairing and cowling shows signs of severe overstress such as crushing buckling or misalignment 3 Tracks rollers hinges or latches are damaged in danger of becom
227. r Equivalent Filler Compound 6 Patch Plates Cherry Rivets item 38 Appx C eRivet Gun Solvent item 47 Appx C PROCEDURAL STEPS 1 Remove damaged skin and core using a router to route all damage on outer and inner skins Enlarge the hole on the outer skin and honeycomb so that a 1 Inch rim surface of the inner skin is exposed as shown 4 26 2 Make two patch plates One patch plate is for inner skin the other for the outer skin Figure 4 27 3 Apply sealant to exposed surface of inner skin Assemble patch plate to the inner skin with cherry rivets 4 Completely fill void with metal set fill compound Add slight excess to allow for shrinkage 5 Let harden Sand smooth Apply sealant to the area between the outer patch and skin Assemble patch to outer skin with 1 8 cherry rivets 6 Record BDAR action taken mission is complete as Soon as practical repair the equi pment system Using standard maintenance procedures When OPTION 4 Damage Over 8 Inches to Both Skins and Core LIMITATIONS None PERSONNEL TIME REQUIRED el Soldier e2 Hours 55 1520 228 BD AI RFRAME MATERIALS TOOLS REQUIRED Patch Plates eCherry Rivets PROCEDURAL STEPS 1 Remove damaged skin and core Figure 4 28 Clean top and bottom skins 6 inches around holes with cleaner The maximum damaged area that may be cut out is 12 inches 2 two patch 0 04 inch or thick
228. r longeron to extend at least six faste ners on all rows fore and aft of damaged section Sometimes a single substitute cap or longeron can be extended to pro vide support for several damages This is better than individual repairs as it will stiffen the airframe 4 In the areas where the substitute cap or longeron will overlap on the damaged cap or longeron sections remove rivets which attach the damaged cap or longeron to skin Back drill rivet holes on the substitute cap or longeron to match existing holes on the damage cap or longeron 5 Rivet the substitute cap or longeron in place using the same size or larger rivets as those removed in step 4 Rivet patch plate over hole using blind rivets Use same size rivets as existing rivets NOTE Stiffener can be placed on out Side however this configuration is nonpreferred Record BDAR action taken When mission is complete as soon as practical repair the equi pment system Using standard maintenance procedures TM 55 1520 228 BD AI RFRAME OVERLAP DAMAGED LONGERON WITH SUBSTITUTE LONGERON BY 1 1 2 2 FT i EENE 1 1 2 MIN 272722724 4442427 ADD SECOND ANGLE IF BOTH WERE DAMAGED SECTION A A Figure 4 20 Expedient Cap Longeron Repair TM 55 1520 228 BD Al RFRAME 4 19 FRAME BULKHEAD SKIN AND the repair strap will overlap on the damaged STRINGER DAMAGE bulkhead flange and s
229. r with Shield terminator of wire repair kit with temperature set at 900 F 4 Terminate the ground lead as directed in aircraft wiring manual 5 Record BDAR action taken When mission is complete as soon as practical repair the equipment system using standard maintenance procedures TM 55 1520 228 80 ELECTRICAL AND AVIONICS SYSTEM 2 Position ground lead and shield ter mi nator as shown in Figure 11 21 3 Heat shield terminator until solder ring melts then continue heating for an additional 15 seconds or until sleeve starts to turn brown Use reflector with temperature set at 900 F 4 Terminate the ground lead as directed in the aircraft wiring manual 5 Record BDAR action taken When mission is complete as soon as practical repair the equipment system using standard maintenance procedures END STRIP BRAID FOLDED BACK pears 30 25 30 Figure 11 19 Shield Terminator Repair I r ES 11 11 TERMINATORS FOR NI CKEL PLATED SHIELDS INCLUDING VERMILLION WINDOW STRIP END STRIP GENERAL INFORMATION The kit contains shield terminators for nickel plated Shields including vermillion LI TATIONS This is a permanent repair Figure 11 20 Nickel Plated Shield Terminator Preparation PERSONNEL REQUIRED Soldier e 15 Minutes GROUND LEAD MATERI ALS TOOLS REQUIRED CABLE e Shield Terminator item 10 Appx Reflector item 10 Appx B Heat Gun Heat Source St
230. ractical repair the equi pment system Using standard maintenance procedures ON 2 Plastic Hole or Crack in Duct Rigid LI MI TATIONS PERSONNEL TIME REQUIRED e 1 Soldier e Hour MATERIALS TOOLS REQUIRED e 0 016 inch Sheet Metal Mini mum e Sealant item 4 Appx 400 Grit Sand Paper item 45 Appx C e Cleaner Naptha or Equivalent item 1 Q e Glass Tape or Aluminum Tape item 60 Appx C PROCEDURAL STEPS 1 Locate damaged area and remove panels and or other items as necessary to gain access to the duct to be repaired Refer tp Figures 15 2 and 15 3 for locations of rigid plastic ducts 2 Cut a patch out of sheet stock Patch should extend 1 1 2 inches from the edge of the hole at all points Inspect after every flight 3 Stop drill any cracks which might be extending from hole 4 Sand both the bottom surface of the patch and the surface area around the hole to be covered by the patch 5 Clean surface with solvent 6 Apply sealant to patch and on the surface area that will be covered by the patch Press patch in place and wrap glass tape around patch and duct to hold the repair in position 8 Record BDAR action taken When mssion is complete as soon as practical repair the equi pment system using standard maintenance procedures 15 6 FLEXIBLE DUCT DAMAGE GENERAL INFORMATION The flexible ducts are composed of special wire covered fabric with impr
231. rd Structures Repair Kit 0 4920 01 266 7536 Test Equipment Repair Kit Electrical 78286 Test Equipment 10700 20638 041 10 5935 01 254 1688 Wire Repair Kit Special Tools Used 06090 MK 0015 1 for Electrical Wiring Repair Including Repair Parts TM 55 1520 228 BD APPENDIX EXPENDABLE DURABLE SUPPLIES AND MATERIALS LIST BDAR FIXES SHALL BE USED ONLY COMBAT OR FOR TRAINING AT THE DISCRETION OF THE COMMANDER AUTHORIZED TRAINING FIXES ARE LISTED IN APPENDIX E IN EITHER CASE DAMAGES SHALL BE REPAIRED BY STANDARD PROCEDURES AS SOON AS PRACTICABLE Section INTRODUCTION C 1 SCOPE This appendix lists expen b National Stock Number This is dable supplies and materials needed to the National stock number assigned to make BDAR fixes on the OH 58 helicopter the item use it to request or Items are listed alphabetically by the requisition the item 1 shown in the description column I These items are authorized to you by Description Indicates the CTA 50 970 Expendable Items Except Federal item name and if required a Medical Class V Repair Parts and description to identify the item The Heraldic Items or CTA 8 100 last line for each item indicates the Commercial and Government Entity Code C 2 EXPLANATION OF COLUMNS CAGEC in parentheses followed by the part number ltem Number This number is assigned to the entry in the listing and d Unit of Issue 15 the abbre is referenced in the narra
232. receding the hard copy 2028 For the World Wide Web use https amcom2028 redstone army mil Distribution Statement Approved for public release distribution is unlimited TABLE OF CONTENTS HOW TO USE THIS MANUAL CHAPTER GENERAL INFORMATION Section I Introduction Standards and Practices Tasks and Responsibilities Section II Section III CHAPTER 2 ASSESSING BATTLEFIELD DAMAGE Section I Section II Introduction General Fault Assessment Table CHAPTER 3 GENERAL REPAIRS CHAPTER 4 AIRFRAME Section I Section II Introduction ee Expedient Structural Repairs CHAPTER 5 ALIGHTING GEAR Section I Section II Section III Introduction Skid Tube Skid Damage CHAPTER 6 POWER PLANT INSTALLATION Introduction Section I Component Expedient Fixes Section II Page vill I el N Coll A O ps 9 o1 A OY I Change 1 i 55 1520 228 BD TABLE CONTENTS Cont ROTORS Section I Introduction Section Repairs CHAPTER 8 DRIVE TRAIN SYSTEM Section Introduction Section Repair CHAPTER 9 HYDRAULIC Section I Introduction Section Lines and Hoses tue s Section III Seals Packings and Gaskets CHAPTER 10 INSTRUMENTS Section I Section I Introduction
233. removed or bypassed any input will result in erratic engine response At all times the integrity of all fuel control lines must be maintained No lines may be deleted or plugged NOTE Should any of the three components sustain damage or otherwise be rendered inoperable the remaining functional items should be recon nected In emergency situations when time is of the essence the complete system may be bypassed option 2 in the most This option results unstable condition for the pilot and is therefore least desirable OPTION 1 Remove Defective Component LI MI TATIONS PERSONNEL ME Sol di er 30 Mi nutes Erratic engine response REQUI RED 6 3 TM 55 1520 228 BD POWER PLANT MATERI 15 70015 REQUIRED Flex Line Tubing ID 0 25 in Length 12 in min No 4 Fittings PROCEDURAL STEPS 1 All connections and fittings throughout the system incorporate the Same thread pattern and therefore a variety of configurations may be achieved Should the system be inoper able remove only the defective compo nent s and reconstruct the system Refer to Figure 6 3 to determine possible alternatives 2 Reuse existing o rings when possible If o rings are severely damaged scavenge off removed component CAUTI ON lines must be No lines may be plugged 3 Insure the lines between the fuel control and the governor are intact and not leaking All fuel control maintained de
234. ripper or Knife Insulating Sleeve item 10 Appx B SHIELD TERMINATOR PROCEDURAL STEPS 1 Prepare cable for repair Refer to Figure 11 21 Nickel Plated Shield Termi nator Repair 11 25 TM 55 1520 228 BD ELECTRICAL AND AVIONICS SYSTEM 11 12 TERMINAL BOARDS MATERI ALS TOOLS REQUIRED e Strippers or Knife GENERAL INFORMATION The terminal Replacement Terminal Lug TabTe boards provided are all 5 inches in length They are located in the wiring e Crimp Tool item 10 Appx kit They can be cut to shorter lengths using a hacksaw The general PROCEDURAL STEPS procedure is as follows 1 Select a terminal to fit both the LIMITATIONS Permanent repair wire and the terminal stud Table 11 6 PERSONNEL REQUIRED 2 Strip the wire to the length 1 Soldier specified in Table 11 6 e Time will depend on the number of Wires on the terminal board in 3 Open the dies of the crimp tool question Refer 11 22 MATERI 15 TOOLS REQUIRED 4 Place terminal in proper cavity of e Replacement Terminal Board crimp tool dies see Detail A of Figure item 10 Appx B 11 27 Sizes are stamped below each cavity on side of die PROCEDURAL STEPS TERMINAL 1 Tag and disconnect wires one at a ti me 2 Remove terminal board 3i Install replacement terminal board 4 Connect wires to duplicate the original installation 5 Record BDAR action taken When mission is complete as so
235. rmation on DA Form 2404 and clearly mark the member f Detecting Structural Damage in Adjoining Areas 1 Secondary damage can be the result of severe overstress explosive blast or maneuvering loads imposed on damaged structures Inspect the airframe near the projectile damage for vidence of secondary damage 2 Inspect the skin for creases wrinkles and dents Inspect fasteners for chipped or flaked paint looseness and serviceability If these conditions are evident remove access panels and doors to inspect members for cracks and structural changes Inspecting for broken and missing fasteners Inspect fasteners for security shear pull through tear out and elongated fastener holes Where possible sides inspect fasteners from both h Inspecting for Delaminations Inspect honeycomb structures for voids and delamination using the coin tapping method TM 55 1520 228 BD AIRFRAME 1 Marking and Recording Damage 1 Record all detected damage Refer to Table 4 for repair referral of repair on structural member a Record name of aircraft section containing the damaged element b Record the name of the damage element such as frame stringer or skin panel c Describe the location of the damaged element such as station waterline butt line or panel location d Describe the damage to the element using terms such as hole crack or buckle e Continue da
236. rque Support 179 92 58 27 0 88R Support amp Fittings pup 18162 73 37 No Damage Allowed Engine Pan 130 00 14 12L Horizontal Stiffeners 130 00 14 12L Web amp Drain 130 00 14 12L Spot Weld Damage 130 00 14 12L Doublers Splices Canted Web 130 00 51 67 25 00 Stiffeners 130 00 51 67 25 00 Web 5 40 5 192 84 59 98 7 00L amp R AINVYAYIV 9 8 0 0 91 99 WL 9 Table 4 6 Damage Limits Fuselage Condition II Cont DAMAGE LIMITS COMPONENT PERTON ELEMENT FLANGE SKIN WEB NOTES MEMBER CAUTIONS FS w BL Shear Web 192 84 7 00 Stiffeners pre N x CL 206 35 4 00L amp R EOS 40 0 0 5 192 84 60 00 7 00 Webs 206 35 4 00L amp R Electrical 130 00 29 47 Inserts Compartment 167 00 34 46 Damage Su to T Inserts to Each Floor roup of Four 130 00 29 47 Honeycomb Damage 167 00 34 46 Within 2 of Effective Inserts Bulkheads 142 154 Frame Section 167 179 1 10 192 142 154 Stiffeners Clips 167 179 Doublers 0 70 192 142 154 Splices 167 179 No Damage Allowed 192 Bulkhead 2684 o fs P men as Gps hul s Engine Mount 8 465L amp R Back Structure 130 00 7 3 50L amp R No Damage Allowed 142 33 72 00 12 96L amp R No Damage Allowed 9 8 2 0291 99 NL Lv v Table 4 7 Damage Limits Tail Boom and Landing Gear Condition Il DAMAGE LIMITS ELEMENT Tail B
237. rs DIRECTIONAL GYRO 6615 00 167 9757 COMPASS TRANSMITTER 6605 00 531 299 AN ARC 114 821 00 935 50 RADIO SET AN 115 821 00 935 5072 INVERTER 841 01 140 0941 ELECTRICAL INDICATOR 6620 01 065 3740 HOT AIR MIXING VALVE 1810 01 089 4105 INDICATOR GAS PRODUCER 6620 01 032 3937 INDICATOR TURN amp BANK 0 MAGNETIC BRAKE 1680 00 909 8098 PRESSURE ALTIMETER 6610 00 935 4 ATTITUDE INDICATOR 6610 01 029 670 ICS 5895 00 995 4175 0 4 TM 55 1520 228 BD APPENDIX D Table 0 2 Spare and Repair Parts Cont A TA TU H TU TU TU TU U TU TU H 1 T L 7 AN ARC 114 A B 5821 00 165 2970 ees 5985 00 892 0895 X Was 6140 01 068 8572 X X BATTERY 6140 00 228 8447 IGNITER EXCITER 2935 00 064 9435 X X ar NOUN NSN NOUN NSN MACHINE GUN 7 62MM 1005 00 903 0751 AMMO CHUTE FLEX 7 62 1005 00 027 4217 DRIVE MOTOR 1005 00 832 4549 FEEDER DELINKING 1005 00 921 6241 NOTE 1 Components marked X are 100 interchangeable and have the same NSN i the major components may be removed and substituted however the level of es diss wth the field tools and skill levels available 0 5 TM 55 1520 228 BD APPENDIX D Section 11 B 3 SCOPE This section explains the use of substitute fuels to be used on the 0H 58 helicopter able D 4 lists some possible U S fuels in proper priorit
238. s for type of system item high pressure low pressure etc Cap Terminate or block the system to prevent leakage Repl Replace damaged part repairs not acceptable OK No repairs required Tag Repair instructions are written on tags tied to indivi dual damaged lines components Figure 1 3 Damage Assessment Markings Sheet 2 of 3 55 1520 228 BD GENERAL INFORMATION System identification markings are primarily abbreviations of the system MARKINGS SYSTEM MEANING Sys Damage to unknown system Fuel Fuel Hyd Hydraulic HP High Pressure LP Low Pressure Elect Electrical AV Avionics Flt Cont Flight Control Main Rotor Main Rotor Group Tail Rotor Tail Rotor Group Air Pneumatic Air Cond Air Conditioning BL Air Bleed Air System LC Boundary Layer Control N Nitrogen 0 Eng Contr Engine Control Pow Tr Power Train EJ Ejection NOTE More than one identification marking may be used to describe the system e g HP Hyd Figure 1 3 Damage Assessment Markings Sheet 3 of 3 1 11 1 12 Blank 55 1520 228 BD CHAPTER 2 ASSESSING BATTLEFIELD DAMAGE BDAR FIXES SHALL BE USED ONLY IN COMBAT OR FOR TRAINING AT THE DISCRETION OF THE COMMANDER AUTHORIZED TRAINING FIXES ARE LISTED IN APPENDIX E IN EITHER CASE DAMAGES SHALL BE REPAIRED BY STANDARD PROCEDURES AS SOON AS PRACTICABLE Section I 2 1 SCOPE a This chapter provides guidelines to use in assessing battl
239. self Jumping or bypassing of a part or component Circular indentations on bearing surfaces The primary vertical structural element Often called frames or walls Wrinkle or crease damage to sheet metal structural elements Loss of metal resulting from overheating The smoothing of a metal surface by mechanical action without loss of material Generally found on plain bearing surfaces Surface discoloration is sometimes present around outer edges of a burnished area A rough edge or sharp projection The removal of needed parts or assemblies from other aircraft equipment or from non essential systems on the helicopter undergoing repair A continuous structural element angle tee or channel shape fastened to the top and bottom of a beam or web A sudden and disastrous event caused by equipment failure which endangers human life Functional wear A rubbing action between two parts having relative motion An examination for verifying Breaking away of small metallic particles An imaginary line running perpendicular to the leading or trailing edge of a rotor blade CLOCKW SE COATING PROTECTIVE COMBAT CAPABLE COMBAT EMERGENCY CAPABLE COMPONENT CONSUMABLE ITEMS CORE CORROSI ON COUNTER CLOCKW SE CRACK CRI PPLE CRITERIA DATA DECONTAMI NATI ON DENT DI SASSEMBLY 55 1520 228 BD GLOSSARY GLOSSARY Cont A circular motion in the direction the hands of a clock rotate when viewed from
240. standard maintenance procedures 3 ROWS RIVETS MIN 1 TOP AND BOTTOM 3 BOTH ENDS Boom Skin Damage 55 1520 228 BD CHAPTER 5 ALIGHTI NG GEAR BDAR FIXES SHALL BE USED ONLY IN COMBAT OR FOR TRAINING AT THE DISCRETION OF THE COMMANDER AUTHORIZED TRAINING FIXES ARE LISTED IN APPENDIX E IN EITHER CASE DAMAGES SHALL BE REPAIRED BY STANDARD PROCEDURES AS SOON AS PRACTICABLE Section 5 1 SCOPE This chapter contains information for deferring repair and expedient field fixes of battle damaged alighting gear assembly The repairs or field fixes can only be applied to the skid tubes 5 2 DESCRIPTION alighting gear assembly Figure 2 1 consists of two tubes 1 and two arched crosstubes 2 and 3 fastened together with skid saddles 4 and attaching hardware The assembly is attached to the lower structure with support assemblies 5 and 6 at four points Section ll 5 5 GENERAL INFORMATION a In battle conditions part of the skid tube may sustain various amounts of damage which may be deferred NOTE The conditions in this paragraph apply only to damage to the skid tube 1 Figure 5 1 b Deferrable skid tube damage Damage to Sections A and E rare may include up to complete rupture 2 Damage to the junction of the crosstubes and skid tube Sections B and D Figure 5 2 may include up to one half of the cross section of the skid tube as long as alighting
241. t I am tired of sleazy CD ROM sellers who take publicly available information slap watermarks and other junk on it and sell it Those masters of search engine manipulation make sure that their sites that sell free information come up first in search engines They did not create it They did not even scan it Why should they get your money Why are not letting you give those free manuals to your friends I am setting this document FREE This document was made by the US Government and is NOT protected by Copyright Feel free to share republish sell and so on I am not asking you for donations fees or handouts If you can please provide a link to liberatedmanuals com so that free manuals come up first in search engines lt A HREF http www liberatedmanuals com gt Free Military and Government Manuals lt A gt Sincerely Igor Chudov http igor chudov com
242. t 5 of 5 TM 55 1520 22 80 RFRAME FS130 00 FS98 80 FS123 62 FS82 86 UPPER SHELL FS117 71 WL51 57 FS73 00 FS36 00 STA 130 00 WL25 25 LOWER SHELL WL20 00 Figure 4 12 Upper and Lower Shell Structure TM 55 1520 228 BD RERAME FS167 00 BL10 18 FS130 00 p BL10 18 FS142 33 7 BL14 12 BL12 96 BL3 50 BL8 46 BL14 12 FS205 74 FS192 00 FS179 00 FS165 00 FS154 00 FS143 00 SHEAR WEB CANTED WEB z ELECTRICAL HONEYCOMB FAIRING FLOOR PANELS Figure 4 13 Aft Fuselage Structure 55 1520 22 80 Al RFRAME 27 FIN BS149 35 5126 05 5102 76 9 BS84 57 CA LA BS78 94 S lt ZA 1227 p d 2 STABILIZER 5182 40 5174 10 598 98 8579 80 8542 59 8531 87 WL67 73 Figure 4 14 Tail Boom 55 1520 228 BD Al RFRAME TRANSMISSION amp ENGINE COWLING FIREWALLS Cowling and Firewalls Figure 4 15 4 28 d Determine the priority of the various required repairs based on repair time difficulty of repair resources available tactical situation and need for the aircraft etc The longest repair time normally is given the highest priority and is most critical 4 13 ALLOWABLE DAMAGE LIMITS Damage limts are calculated on the basis of the OH 58 structural analysis and tend to be conservative Assessors using damage limits to prepare dama
243. t Repair Tube Cutting 5 2 Tubes Flight Control Typical Avionics Configuration NDEX 4 Paragraph TM 55 1520 228 BD NDEX I NDEX Cont Subj ect Paragraph V W Waiver 1 1 Window Shield Window 0 0 2 2 2 4 21 Wire 11 14 Wire Repair Segments Unshielded Wires o acm uox ue RR r r 11 6 XYZ NDEX 5 1NDEX 6 Blank TM 55 1520 228 BD GLOSSARY NOTE eThe terms and acronyms listed herein are defined in relation to BDAR and accordingly may not be used in the same manner in other manuals eAdditional definitions of terms markings and acronyms used during BDAR assessment procedures will be found under paragraph 1 10 Tagging and Identifying BDAR Repairs ABRASI ON ALLOWANCE AP ASSEMBLY ASSEMBLY CLEARANCE ASSESSMENT ASSOCIATED PARTS AXI AL BATTLEFIELD DAMAGE BEAM BEND BORE Roughened surface varying from light to severe A prescribed difference between the maximum condition of mating parts The minimum clearance or maxi mum inter ference between such parts Armor piercing incendary armament round A group of two or more physically connected and related parts capable of disassembly and when combined with other assemblies and parts creates a component The actual fit between two or more mating parts with respect to the amount of clearance or interference betwe
244. t system using standard maintenance procedures When TM 55 1520 228 BD HYDRAULIC 22 Figure 9 6 Properly Burred Tubing SY DAMAGED SECTION Figure 9 7 Damaged Tube Section 9 7 TM 55 1520 228 BD HYDRAULIC Figure 9 8 Splice Repair Assembly Figure 9 9 Repair Fitting and Tube Installation OPTION 2 Substitute with High Pressure Hose damage to section of tubing with bends PERSONNEL TIME REQUIRED e 1 Soldier e 30 Minutes MATERIALS TOOLS REQUIRED 9 Hydraulic Hose Assembly Complete with End Fittings 2 MS Unions 2 MS Fittings Tube Cutter Knife or File PROCEDURAL STEPS 1 Cut and remove damaged section of tubing Figure 9 10 Tube ends must be square 2 Clean ends of undamaged tubing with knife or file 2 Install MS fittings as shown in Figure 9 0 4 Connect MS unions to both MS fittings and complete the repair by connecting a hydraulic hose assembl y from one union to the other 9 11 If the damaged length of tubing is long and more than one hose assembly is required hose assemblies may be spliced together with unions No harm will be done if the replacement hose is too long 5 Clamp at convenient intervals not exceeding 2 feet to rigid supports to secure the line 6 Record BDAR action taken When mission is complete as soon as practical repair the equi pment system using standard maintenance procedures TM 55 1520 228 BD HYDRAULIC 9 8
245. teners on kin panels are indications of struc ural changes by an HEI hit 2 Inspect structural changes in the form of buckling crippling and misalignment caused by overpressure These structural changes are noticeable in areas where one structural member may have to support the load of another broken member Check damaged area to see if there is interference with mechanical moving components 3 Use a straight edge to examine the component for twisting or bowing d Inspecting for Embedded Projectiles and Fragments 1 Inspect for embedded projec tiles which can create the same affect as a hole or crack on a tension member 2 Inspect for embedded projec tiles and fragments in areas which have suffered HEI damage The inspection will reveal that a solid projectile is embedded or has broken apart striking internal components 3 Inspect all structures using bright light and magnifying glass Determine the path entry of the projec tile to aid in finding structures that may have embedded fragments Mark embedded objects and record them on DA Form 2404 e Inspecting for Fire Damage Inspect for fire damage by checking for discoloration of the structure Any discoloration will indicate that the member has been exposed to high tem perature Conduct a hardness test to determine if the temperature of the material has changed If test indicates heat damage record the info
246. the mission is complete as soon as wire braid cover and the inner rubber practical repair the equipment system hose Force onto hose until the edge of using standard maintenance procedures the sleeve is even with the end of the rubber hose OPTION 2 Replace Hose Section with MS Fittings no BDAR hose assemblies 5 Reem inside end of Teflon hose with available For Teflon and rubber hose a square tool or a wooden plug so that edge is smooth and flared to facilitate LIMITATIONS None insertion of the nipple of the MS female fitting PERSONNEL TIME REQUIRED 1 Soldier 6 Slide the MS socket over end of hose e 30 Minutes as far as it will go and hold in vise Insert nipple of MS female fitting into MATERI 15 TOOLS REQUIRED rubber inner tube Figure 9 13 Force Replacement Section of Hose 07 Tube all the way until threads in socket and if needed female fitting together and tighten e Masking Tape item 52 Appx CJ until the gap between the edge of the e Fine Toothed Hacksaw socket and the base of the female MS Fittings socket sleeve and fitting is approximately 0 1 32 inch for female fitting 4 ea rubber and 0 025 to 0 045 inch for e MS Union 2 ea Teflon PROCEDURAL STEPS 7 Prepare the other damaged end of the hose in the same manner 1 Cut out damaged hose section Wrap masking tape or other available tape 8 If no replacement section is around hose over the areas where cuts necessary connect the MS fittings on are to
247. the front An external surface treatment such as paint anodizing electroplating or chemical film used to delay the effects of corrosive or atmospheric elements upon metals The ability of the helicopter to perform the MINIMUM combat mission assignments The ability of the helicopter to perform LIMITED specific tactical mission assignments A group of physically connected assemblies or parts Parts or materials which are consumed by usage or which have a one time usage in depot maintenance activity The inner layer of material used to construct honeycomb structural panels Surface chemical action which results in surface discoloration a layer of oxide rust or removal of surface metal The direction opposite to the direction the hands of a Clock rotate when viewed from the front A break in some type of material Damage to a load carrying structural member which would cause degradation of the helicopters ful mission capability Standards or rules used to judge A group of facts To make an item safe for unprotected personnel by removing neutralizing or destroying any harmful substance A function of Nuclear Biological and Chemical NBC Warfare Indentation in metal surface produced by an object striking with force The operations necessary to reduce an assembly to its separate components and parts 6L05 3 TM 55 1520 228 BD GLOSSARY DI STORTI ON EROSION EVACUATI ON EXPEDI ENT FAILURE MODE
248. tions b Condition 2 Self recovery capable Self recovery may be required to move a damaged aircraft to a repair site or from one site to another when towing is not feasible Self recovery is preferable to disassembly and boxing an aircraft for transportation As time permits proceed as follows 1 Mark all visible cracks and the extent of other structural damage with chalk grease pencil paint tape or other available means so that any growth in the damage can be quickly recognized 2 Perform any feasible on site BDAR fixes as required for self recovery 3 Unload all stores and ammuni ti on Weapons unnecessary equipment 4 The following restrictions are imposed on a recovery flight a Maximum airspeed 50 kts b Maximum engine torque 80 at 0 kts 64 at 16 kts 53 at 32 kts 50 at 50 kts c Maximum flight time 2 hours gradi and smooth to minimize loads on d Use gradual pedal movements aircraft e Land at level soft touchdown from hover attitude c Condition 3 Structural damage exceeding condition 2 limits generally does not allow self recovery The damage may or may not be repairable by BDAR techniques The airframe may be so extensively damaged that no useful or needed functions can be restored within available time and resources These aircraft will be 1 Recovered or evacuated to a facility with the resources to repair the airframe 2 Used as a source o
249. tive instruc viation of the types of units under which tions to identify the material e g material is issued Use cleaning compound item 5 Appendi x C 1 TM 55 1520 228 60 APPENDIX C C 2 ITEM NUMBER l 2 9150 9150 9150 9150 Section Il NSN 00 192 5051 00 932 1945 00 944 7292 00 723 4599 00 057 2354 00 908 3193 00 944 8953 00 985 7246 00 506 8497 00 237 2388 APPENDIX EXPENDABLE SUPPLIES AND MATERIALS LIST DESCRI PTI ON Abrasive Cloth Grit 180 P C 451 Adhesive ENA934 NA B A Type 11 Class 3 81348 Adhesive Epoxy Metal Set 4 33564 9340 Adhesive EX1675 B2 Pro Seal 5890 82 Adhesive General Purpose 81348 EC1300121 Adhesive Silicone Rubber 80244 MIL A 46106 Aliphatic Naphtha 81348 TTN95 Brush Stiff Fiber Bristle 80244 H B 643 Cap Electrical Crimp 9 MS25274 2 C hemical Conversion Coating Alodine 80244 MIL C 81706 Clamp Hose 3 8 to 1 in 10403 MIL C 11569 Clamp Hose 1 1 16 to 2 in 01944 MS35842 12 Corrosion Preventive Compound 80244 MIL C 16173 Cotter Pin Assortment 81348 Ferrul Electrical 22 14 Wire Gage size 10 ea 59730 Fiberglass Cloth 81349 MI L C 9084 Fiberglass Resin 81349 MI L C 9084 Foil Aluminum QQ A 1876 Gasket Cork 1 32 Gasket Material 1 32 in 81348 HH P 96 Grease Aircraft MIL G 81322 54527 Grease Aircraft Aero Shell Grease 54527 Greas
250. tly in a battlefield environment Standard maintenance procedures will provide the most effective means of returning damaged equipment to ready status provided that adequate time replacement parts necessary tools and trained qualified repair persons are available BDAR procedures are only authorized for use in an emergency situation in a battlefield environment and only at the direction of the com mander They are not to be continued after the equipment is out of the battle environment 1 1 55 1520 228 BD GENERAL INFORMATION b BDAR techniques are not limited to simple restoration of minimum functional combat capability full functional capability can be restored expediently with a limited expenditure of time and assets it will be accomplished C Some of the special techniques in this manual if applied may result in shortened life or in further damage to major components of the helicopter Th 6 Fabrication of parts from kits or readily available materials 7 Jury rigging 8 Use of substitute materials c Damage Assessment procedure to rapidly determine what is damaged whether it is repairable what assets commander must decide whether the risk of having one less helicopter available for combat outweighs the risk of applying the potentially destructive expedient repair technique Each tech nique gives appropriate warnings cautions and lists systems limitations
251. top drill a hole at the end of each crack Figure 4 29 If tolerable cut out a hole to include the ends of all cracks This will restrict vision further Smooth ragged edges Drill small holes 1 2 to 3 4 inch spacing 3 8 inch edge distance along both sides of any crack and along the sides of the hole 3 Lace safety wire with needle nose pliers through holes and across cracks and over hole forming a web with 1 2 to 3 4 inch between wires Pul wires tight 4 Brush epoxy sealant over safety wire and crack to make a water tight seal NOTE Holes too large to be closed with safety wire and epoxy may be sealed temporarily with Army green tape 5 Record BDAR action taken When mission is complete as soon as practical repair the equi pment system Using standard maintenance procedures 4 22 TAIL BOOM SKIN DAMAGE GENERAL INFORMATION The tail boom is a basic monocoque structure with no longi tudinal skin stiffeners or longerons The tail boom is unserviceable if damage is extensive enough to cause misalign ment Damage which does not exceed 10 percent of tail boom circumference in height and 30 percent of tail boom cir cumference in length may be repaired by patching Circumference to measured at aft end of damage A maximum of TWO damaged areas per stress section of the tail boom is permitted Example a line drawn around the circumference of the tail boom must not touch more than TWO damaged areas Damaged
252. tringer remove rivets and back drill if the area is accessible If back drilling GENERAL INFORMATION A damaged flange is not feasible interpitch new rivets between on a bulkhead or frame could be repaired from existing rivets the outside in the same way as i5 a Cap or longeron However it is not desirable to have a 4 Rivet the repair strap to the bulkhead or Section on the outside of the aircraft sticking out frame the same size or normal to the airstream Frame flanges are larger rivets Rivet the strap to the skin using two therefore repaired by applying a strap over the rows of rivets around t 2 using the damage If the damage to a highly loaded Same size rivets as in adjacent skin flange bulkhead 15 severe then treat it like a cap and let structure the section stick out in the airstream 5 Record BDAR action taken When mission is OPTION 1 Patch Plate Repair for Smal complete as soon as practical repair the Damage equipment system using standard maintenance procedures LIMITATIONS None Condition 1 Inspect after every flight OPTION 2 Combination Repair for Major Frame or Bulkhead Damage PERSONNEL TI ME REQUI RED e 2 Soldiers LIMITATIONS None Condition 1 e 2 Hours Inspect after every flight MATERI 15 TOOLS REQUIRED PERSONNEL TIME REQUIRED Repair Strap e 2 Soldiers Cherry Rivets item 41 Appx C e 3 Hours Tape or Skin Patch MATERI ALS TOOLS REQUIRED PROCEDURAL STEPS
253. ts Forward Fuselage Condition II Cont DAMAGE LIMITS COMPONENT LOCATION SKIN WEB NOTES MEMBER CAUTIONS FS 3NVvadaiv 9 8 2 0291 99 NL gt gt z O m wma 51 72 72 00 B r N Bulkhead FS130 D N x WL Upper Inboard Outboard Frames Webs 51 72 Frame Webs 130 72 00 51 72 Clips Splices 130 72 00 Supports Flanges Bulkhead FS130 29 70 Honeycomb Panel Lower 130 51 52 ME I 2 1 20 130 1 20 20 00 Honeycomb Panel 29 70 Aft Cabin 120 00 50 04 Inner Skin and Enclosure 130 00 69 00 20 55L amp R Doublers 117 71 50 04 Outer Skin 130 00 67 20 25 251 117 71 50 04 Outer Skin and Door 130 00 67 20 25 25R Panel 117 71 50 00 Intercoastals 130 00 72 00 Between Inner amp 25 25L amp R Outer Skin 117 71 50 04 Angles Support 130 00 72 00 25 25L amp R Flanges Stiffeners i N J z Aft Cabin 120 00 63 71 Gun Mount Channel 1 50 3 Enclosure 130 00 20 00L i 5 Pylon Support 98 80 73 93 7 52L amp R Forward Support No Damage Allowed 119862 7192 625L8R Support No Damage Allowed Cabin Roof Beam 80 46 67 92 Beam Left and Right 101 67 67 92 Bulkheads Between Table 4 5 Damage Limits Forward Fuselage Condition Cont DAMAGE LIMITS COMPONENT LOCATION MEMBER Cabin Roof Beam 67 92 3 00L Bulkhead Skin and 71 9
254. uges indicate a stall sent do not overreact A quick shutdown of engine will decrease NI RPMs reducing pressure at the inlet causing the fire to come forward through the engine is pre hold the f Nl does not pickup d If gauges indicate stall throttle firmly RPM slowly decrease throttle fuel demand WARNING If stall condition is overcome engine must now be run in ful power operation If engine start is achieved N1 must be maintained above 80 percent Reduc tion to part speed operation could in troduce possible stall implications resulting in engine flameout without auto relight capability 7 Record BDAR action taken mission is complete as soon as practical repair the equi pment system using standard maintenance procedures When AIR BLEED VALVE 2 NI BLOCKING PLATE TM 55 1520 228 BD POWER PLANT MOUNTING BOLTS 3 Figure 6 2 Blocking Plate Installation 6 6 DOUBLE CHECK VALVE INOPERATI VE GENERAL INFORMATION The double check valve along with both accumulators is Situated in line between the power tur bine governor and the fuel control and acts as a dampener for surge control This system feeds into the fuel control to insure a steady stream of secondary fuel should the compressor flow become inconsistent It also decelerates a quick reaction from pilot input With these factors in mind the pilot must be made aware that if any component of the system is
255. ui ker 8 32 TERMINAL LUG damaged circuit breaker 9 Secure fuse link to other wiring with tape to avoid pinching wire when circuit breaker panel is closed 10 Clean up damaged area behind circuit breaker panel to remove debris Figure 11 36 Typical Circuit and use tape to insulate any damaged Breaker Connection parts that might cause electrica shorts Table 11 7 Fuse Link Strands 11 Carefully close circuit breaker panel and secure by turning duze fasteners clockwise CIRCUIT AWG BREAKER SIZE NO OF AMPERAGE WIRE STRANDS 12 Record BDAR action taken When mission is complete as soon as practical repair the equipment system using standard maintenance procedures ORIGINAL LINE TERMINAL LUG NEW TERMINAL LUG 1 IN lt N ja TAPE NOTE Try to use inner strands of wire that are not cut or nicked by knife used to remove insulation t INSULATION FUSE LINK Remove line side Figure 11 37 by unscrewing 8 32 screw Repeat for LINE SIDE supply side NEW TERMINAL LUG Twist the No 38 AWG strands of wire from step 5 together and insert the end of line side of terminal lug wrap and twist as shown in Figure 11 37 Slip 1 inch piece of insulation over Figure 11 37 Construction of Fuse Link 11 37 TM 55 1520 228 BD ELECTRICAL AND AVIONICS SYSTEM 11 22 BUS BARS GENERAL INFORMATION Rigid bus bars are used in the
256. uld allow plastic to fall into moving mechanical parts On the outside of cables or bundles that will be dragged through tight or unreachable spaces during final aircraft installation e Where failure of the strap would per mit movement of the wiring against parts which could damage the insulation or allow wiring to foul mechanical linkages high vibration areas n areas of severe wind or moisture problems When use of these straps is prevented by these restrictions use tie tape for secondary ties between clamps PERSONNEL ME REQUIRED 1 Soldier e 1 Minute MATERI ALS TOOLS REQUIRED e Self Clinching Cable Strap item 10 Appx B Cable Strap Tool item 10 Appx PROCEDURAL STEPS the bundle the large end 1 Position the strap around with the flat side of against the bundle 11 27 55 1520 228 BD ELECTRICAL AND AVIONICS SYSTEM 2 Thread tip through eye then hand pull strap tight against the bundle Refer 11 23 3 Adjust the tool 4 Pass the free end of the cable tie through the slot in the end of the tool then push tool snugly against the strap Figure 11 24 5 While holding strap firmly against side of tool and tool faces squarely against large end of strap pump handle several times without fully activating the tool s cutting knife Once the strap has been stretched to its maximum Squeeze handle slowly and firmly unti strap is cut WARNI N
257. un Mount Channel D N x CL DENxWL 55 ono Jao o Pylon Support 98 80 73 93 7 52L amp R Forward Support No Damage Allowed 123 62 7192 625L amp R Aft Support No Damage Allowed No Damage Within 3 Radius of Inserts Cabin Roof Beam 80 46 67 92 Beam Left and Right 101 67 amp 67 92 Bulkheads Between 67 92 3 00L Bulkhead Skin and 200 5 120 90 71 96 3 00R Doubler i 80 46 3 00L Bottom Skin and 5 130 00 67 92 3 00R Access Cover Lower Cabin Shell 73 18 20 00 18 40 Radius and Edge of 5 113 00 25 25 Outboard Honeycomb Panel 18 40L Honeycomb Panel i 18 40R 113 00 20 00 Honeycomb Panel No Damage 130 00 54 65 Within 3 Radius of Inserts 5644 2000 Splice 075 150 36 00 20 00 Frames Angles Upper Cabin Roof 54 48 Top Skin Shell 82 86 82 86 Honeycomb Panels 125 00 14 12L amp R Honeycomb Panels Outboard 14 12L Titanium Panel 14 12R 3Nvaadaiv 9 8 2 0291 99 NL S r Table 4 2 Damage Limits Forward Fuselage Condition I Cont LOCATION DAMAGE LIMITS MEMBER ELEMENT CAP FLANGE SKIN WEB NOTES MEMBER CAUTIONS cL N Upper Cabin Roof 54 48 B Flanges Formers DUN x CD 130 00 L Stiffeners Supports Landing Gear 73 00 amp 18 30 amp 13 30L amp R Support Fitting 130 00 20 75 amp Flanges Damage Allowed on One Flange 10 25L amp R 130 00 20 75 10 25L amp R Cross Tube A
258. ure 11 32 LIMITATIONS Will be dependent on the type of splice used Typically tem porary repair PERSONNEL TIME REQUIRED e Will be dependent on the type of splice used Typically 1 soldier 15 30 minutes per splice MATERI 5 TOOLS REQUIRED Will be dependent on the type splice used PROCEDURAL STEPS l Identify wires to be bridged together 2 Splice wires and jumper wires together using one of the splicing techniques of this chapter 3 Secure jumper wires after repair is made 4 Record BDAR action taken When mission is complete as soon as practical repair the equi pment system using standard maintenance procedures JUNCTION BOX BULKHEAD OR DISTRIBUTION EXTERNAL LINK IN LINE REPAIR Figure 11 32 Component Bypass 11 20 CONNECTOR REPAIR GENERAL INFORMATION Deformed crushed missing or otherwise damaged connectors can be replaced or repaired If a replacement connector is not available to replace a crushed connector clean up fragments of the connector and use jumper wires to bridge wire ends together If only part of the connector has been damaged and there are unused pins sockets on the connector which are undamaged wires on both sides of the connectors can be moved to the unused good pins sockets Also any available undamaged pigtails on the connector may be used OPTION 1 Damaged Pins or Sockets No Damage to Connector LIMITATIONS None PERSONNEL TIME REQUIRED
259. ve normal tem perature Several repairs can be applied depending on accessibility and 2 can result in less than the the nature and extent of damage incurred Various repairs are shown at Figure 8 3 8 1 8 2 TM 55 1520 228 BD DRIVE TRAIN SYSTEM Mast 10 Disc Assy Transmission Assy 11 Bearing Hangar and Support Main Driveshaft Bracket Freewheeling Assy 12 Hangar Blower Assy Forward Short Tail Rotor 13 Oil Cooler Driveshaft 14 Coupling Main Driveshaft 011 Cooling Blower and 15 Splined Adapter Shaft Assy 16 Oil Filter Assy Aft Short Tail Rotor Driveshaft 17 Tail Rotor Driveshaft Long Tail Rotor Driveshaft Segment Tail Rotor Gearbox Assy V p 4 KA 11 i 11 11 11 10 212 SEE DETAIL A PRIOR TO COMPLIANCE WITH MWO 55 1520 228 50 25 Figure 8 1 Drive Train System Sheet 1 of 4 8 3 Figure 8 1 Drive DETAIL A Train System TAILBOOM TYP REF BEFORE MWO 55 1520 228 50 25 Sheet 2 of 4 TM 55 1520 228 BD DRIVE TRAIN SYSTEM 7 Tg adnb y f 30 19946 waysks antag 123 4 TUTET AFTER COMPLIANCE WITH MWO 55 1520 228 50 25 11 10 EN 1 P c W31S5A4S JAIXO 09 622 0291 96 Wl TM 55 1520 228 BD DRIVE TRAIN SYSTEM ears HANGER SUPPORT BRACKET ON TAILBOOM TYP REF 11
260. vets around patch plate in webs and skins using same size as adjacent rivets in webs and skin 5 Record BDAR action taken mission is complete as soon as practical repair the equi pment system Using standard maintenance procedures 4 18 CAP OR LONGERON DAMAGE GENERAL INFORMATION Nondeferrable cap or longeron damage may be substantial combined with skin damage It will generally be necessary to repair the cap or longeron first and then the skin It may not be necessary to repair the skin for structural reasons but generally skin repair is recommended to make a watertight repair LIMITATIONS None Condition 1 Inspect after every flight for damage growth PERSONNEL TIME REQUIRED 2 Soldiers e 2 Hours MATERIALS TOOLS REQUIRED Longeron or Cap Sections used in outside repairs should be angular or channel shaped The strength of the new cap or longeron should at least that of the damaged cap or longeron Refer 4 8 for substitute materials to use on repair if a longeron or cap section is not 1 e Skin e Blind item 41 Appx C When 55 1520 228 80 RFRAME PROCEDURAL STEPS 1 Remove sections of the aircraft skin containing the damage Do not cut cap or longeron but cut off ragged ends Figure 4 20 2 Make a patch plate Plate should be as strong or stronger than original skin Overlap the hole for at least 2 rows of rivets 4 Cut a piece of substitute cap o
261. vis bolt would normally fit mash the tube only enough to fit over the bearing assembly with some clearance Round off the end of the tube Figure 13 11 55 1520 228 BD FLIGHT CONTROLS SYSTEM Figure 13 2 Collective Flight Control FLIGHT CONTROLS SYSTEM TM 55 1520 228 BD LATERAL Figure 13 3 Cyclic Flight Control 13 6 55 1520 228 BD FLIGHT CONTROLS SYSTEM Figure 13 4 Flight Control Actuators 13 7 55 1520 228 BD FLIGHT CONTROLS SYSTEM NOTE THIS IS A CONFIGURATION OF THE OH 58A SERIES HELICOPTER Figure 13 5 Anti Torque Controls Sheet 1 of 2 55 1520 228 BD FLIGHT CONTROLS SYSTEM NOTE THIS IS A CONFIGURATION OF THE OH 58C SERIES HELICOPTER Figure 13 5 Anti Torque Controls Sheet 2 of 2 13 9 TM 55 1520 228 BD FLIGHT CONTROLS SYSTEM Refer to Figures 13 2 thru 13 5 Figure 13 6 Control Tube Dimensions SLEEVE OVER ROD OR TUBE INSERT ROD OR TUBE STRUCTURAL ANGLES SPLINT fs ARS AM 5 Figure 13 7 Suggested Repair for Control Rods or Tubes 13 10 55 1520 228 BD FLIGHT CONTROLS SYSTEM Table 13 2 Nominal Tube Splice Sizes 1680 00 125 8871 206 001 174 3 3040 01 010 6779 206 001 096 7 3040 00 179 6880 206 001 306 11 3040 01 012 5969 206 001 096 1 3040 01 017 7587 206 001 194 5 3040 01 007 5514 206 001 194 1 3040 01 018 9710 206 001 099 1 206 001 189 5 3040 00 483 8616 206 001
262. y that may be used Table 0 5 lists primary or standard fuel sources and alternate fuel sources for various countries Table D46 lists some commer cial fuel sources that may be substi FUELS When using substitute fuels it is preferable to premix the fuels in a container for better blending before pouring into tank This method o mixing the primary fuel with a substi tute fuel insures that the fuels mix completely The best expedient fueling method is to add both fuels at the same time from two separate fuel lines n tuted for the primary or standard 4 Table D 7 1515 alternate and expedient fuel and also some alternate fuel sour uel blends P 8 ces which are similar to JP 5 and JP 8 4 GENERAL When fuel is pumped into a combustion chamber with the correct air mixture it can be ignited and wil burn in a controlled manner The spe cial additives the fuel contains pre vents carbon deposits and corrosion build up which in turn helps engine performance 8 5 MANNER OF BLENDING FUELS a The fuel to be used on an OH 59 helicopter has to meet certain charac teristics so that starting and perfor mance will be satisfactory These criteria are viscosity pour point and cloud point b Some substitute fuels which alone cannot be used on the OH 58 helicopter can be blended with a primary fuel and can then be utilized for engine operation 0 6 d There is no special limitation on the use
263. ype Kerosene Type 748 748 BELGI UM PF PF al AF n AF BA PF 7 AF CANADA 6P GP DENMARK 7 5571 D Eng RD 2453 Eng RD Grade P 4 155 3Amd 2 AF FRANCE ATR AF ATR 3405 C n a AF FEDERAL REPUBLTC 9130 006 T TL 9130 007 155 4 Ss OF GERMANY n a AF n AF GREECE MI L T 5624 Grade P 4 ITALY M C 0 M C M C n al AF n AF Amd 1 AF LUXEMBOURG Eng RD Eng RD Grade P 4 a AF 155 6Amd 2 n AF ss jAmd 2 a AF Grade P 4 AF Grade P 4 AF AIR 3405 C AF Grade P 4 a AF UNITED KINGDOM Eng RD Eng RD Eng RD 1ss 3Amd 2 n a AF 1ss 6Amd 2 n a AF 155 2 a AF Grade P 4 n alAF Grade P 5 n AF 8 USSR GOST 10227 62 1 1 15 1 GOST 9145 59 D TM 55 1520 228 BD APPENDIX D Table D 6 Substitute Commercial Fuels SOURCE ALTERNATE FUELS U S MILITARY FUEL J P 5 MIL T 2624 J P 8 MI L T 83133 NATO CODE NO F 40 F 44 34 COMMERCIAL FUEL ASTM D 1655 ET B JET A ET A 1 American Oil Co American P 4 American Type A Atlantic Richfield Arcojet 1 Richfield Div Richtield A Richfield A 1 B P Trading BP Caltex Petroleum D s Corp Caltex Jet B Caltex Jet A 1 City Service Co amo A Continental Oil Co et 50 Conoco Jet 60 Exxon Co U S A Exxon A Exxon 1 Gulf Oil Gulf Jet B Gulf Jet A Gulf Jet A 1 Mobil Oil wobil et A Mobil Jet A 1
264. ystem and Equivalents Linear Measure 1 centimeter 10 millimeters 39 inch 1 decimeter 10 centimeter 3 94 inches 1 meter 10 decimeters 39 37 inches 1 dekameter 10 meters 32 8 feet 1 hectometer 10 dekameters 328 08 feet 1 kilometer 10 hectometers 3 280 8 feet Weights 1 centigram 10 milligrams 15 grain 1 decigram 10 centigrams 1 54 grains 1 gram 10 decigram 035 ounce 1 dekagram 10 grams 35 ounce 1 hectogram 10 dekagrams 3 52 ounces 1 kilogram 10 hectograms 2 2 pounds 1 quintal 100 kilograms 220 46 pounds 1 metric ton 10 quintals 1 1 short tons ce de de he eee 5 eee sq sq sq sq sq sq Liquid Measure ntiliter 10 milliters 34 fl ounce ciliter 10 centiliters 3 38 fl ounces liter 10 deciliters 33 81 fl ounces kaliter 10 liters 2 64 gallons ctoliter 10 dekaliters 26 42 gallons kiloliter 10 hectolitas 264 18 gallons Square Measure centimeter 100 sq millimeters 155 sq inch decimeter 100 sq centimeters 15 5 sq inches meter centare 100 sq decimeters 10 76 sq feet dekameter are 100 sq meters 1 076 4 sq feet hectometer hectare 100 sq dekameters 2 47 acres kilometer 100 sq hectometers 386 sq mile Cubic Measure centimeter 1000 cu millimeters 06 cu inch decimeter 1000 cu centimeters 61 02 cu inches meter 1000 cu decimeters 35 31

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