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1. K al il Ny TIDAL INFORMATION Fig 5 8 Excerpt from NOS Chart No 12314 Delaware River Philadelphia PA to Trenton NJ Three ranges are shown on this inset The rear range marker for the Kinkora Range is an occulting white light with a 4 second period The front range marker for this same range is a quick flashing white The boundary between the Roebling Range and the Kinkora Range is close to the unlighted red nun 70 Green buoy 71 is a lighted quick flashing buoy The reason that the quick characteristic is used is that two course changes are necessary over a short distance Landmarks shown include tanks and a spire 0 34 NOAA Chart User s Manual distance off Maxim a single radiobeacon can be calculated from the length of the dog leg and the degrees of bearing change Radiobeacons are typically located at or near harbor entrances to maximize the utility of the homing or tracking capability of the system The LOP from a radiobeacon can be crossed with another LOP e g from a nearby radiobeacon or visual aid to determine a fix Mariners using radiobeacons for tracking or homing purposes are cautioned to keep track of the vessel s position so as to avoid running aground or into hazardous waters Historical examples see Maxim of homing without dis tance checks abound Additional material on radiobeacons can be found in the references listed at the end of this chapter e g Bowditc
2. NOAA Chart User s Manual tional light normally shows three adjoining sectors of red white and green with the cen ter white beam oriented to mark the channel Leading Light A leading light see Section P 20 of Chart No 1 for chart conventions is similar to a range light or marker see below except that it marks a channel with a single light with ray lines rather than with two separate lights It is usually a high intensity beam marking the safe channel which diminishes to much lower intensities around the remainder of the hori zon It differs from a directional light see above in that it shows only one color of light instead of the three color sectors of the direc tional light Aeronautical Lights Aeronautical lights see Section P 60 of Chart No 1 for chart conventions are white and green navigation lights associated with air ports and often found atop the control tower Because these are generally attended during their hours of operation the lights are highly dependable Moreover these are often the most conspicuous of the nonstrobe lights and their nominal range may be greater than those es tablished for marine navigation The aeronau tical light is charted by a standard light dot with magenta flare The light symbol is accom panied by its characteristics and the label AERO Articulated Lights An articulated light is a floating light also called a buoyant beacon It is basically a verti cal
3. U S Department of Transportation United States Coast Guard Aids to Navigation COMDTPUB P16502 8 Washington DC May 1988 U S Department of Transportation United States Coast Guard Light List Volume 1 Atlantic Coast St Croix River Maine to Toms River New Jersey COMDTPUB P16502 1 Washington DC 1991 U S Department of Transportation United States Coast Guard ZORAN C User Handbook COMDTPUB P16562 6 Wash ington DC 1992 Walsh G Chartroom Chatter Ocean Navigator Issue No 60 March April 1994 p 14 Wilford J N The Mapmakers The story of the great pioneers in cartography from an tiqguity to the space age Vintage Books New York NY 1982
4. An ae gt a PO napa Of oot PF Aaa a 28 28 oot S saa pas a6 oe ke 21 16 Obsin ren 1957 re BASCULE BRIDGE HOR CL 30 FT 7 cur P VERT CL 15 FT HARBOR S PIPE povio ieor ater ingk ie 9e WE A Lg 433 SN A3 Po 28 r a ef Or NOAA Chart User s Manual DEMARCATION LINE 80 50 1g see note A 4 Island 4 om S ULE Drive 28f vi wood P unger const Budge Q R igg Coble Area Ae BASCULE BRIDGE HOR CL 25 FT TEMPIE VERT CL 8 FT A that the buoys in Hereford Inlet are not charted Note also the daymark symbols marking the Great Flat Thoro Cupolas and a standpipe can be seen as landmarks Lights lighted and unlighted buoys are also shown green and red junction beacons with preferred channel to starboard designated with a GR yellow quarantine area practice area desig nated with a Y and white regulatory warn ing state boundary designated with a W Numbers and letters are charted as appro priate The abbreviation Bn is used to de pict daybeacons which do not have identify ing numbers or letters Daybeacons that have information written on the dayboards may have that information e g Rock charted as an optional part of the aid characteristic Private daybeacons are labeled Priv Aids to Navigation 5 31 Ranges M According to the Light List ranges are non lat
5. A buoy equipped with a marker radiobeacon is called a radiobeacon buoy A buoy with equipment for automatically transmit ting a radio signal when triggered by an underwater sound signal is called a sonobuoy A combination buoy has more than one means of conveying intelli gence it may be called a lighted sound buoy if it is a lighted buoy provided with a sound signal Buoys may be classified according to location as channel mid channel middle ground turning fair way bifurcation junction or sea buoy A bar buoy marks the location of a bar ing or spoilground buoy Buoys used for particular purposes may be classi fied according to their use as anchor anchorage quarantine mooring warp ing swinging marker station watch or position buoy A light weight buoy especially designed to withstand strong currents is called a river buoy An ice buoy is a sturdy one used to re place a more easily damaged buoy dur ing a period when heavy ice is antici pated The above definition also identifies some of the many navigational uses of buoys Per haps the most significant use of a buoy is to enable the mariner to stay in safe water and avoid unseen hazards to navigation As noted buoys are the most common ATON Approximately 25 500 federal buoys marked U S waters in 1993 Buoys may be lighted and or have fog signals see below but most 82 percent are unlighted can or nun buoys Physically buoys are floating ATONs
6. Charting Practices As with other ATONs buoys are charted with a symbol and one or more labels provid ing capsule information about the buoy As noted generally only buoys listed in the Light List are charted In most cases this presents no difficulty for the mariner However there are numerous buoys that are not charted In particular buoys marking channels along the Atlantic coast and gulf coast that shift fre quently are generally omitted Charting these would require excessively frequent revisions Where these buoys are not charted a note is added explaining that these buoys are omit ted In this case a standard note is added to the chart Entrance to Inlets The entrance channels at the inlets not protected by jetties are subject to fre quent changes The buoys are not charted because they are frequently shifted in position Buoys are removed if shoaling makes inlets unnavigable Entries for such buoys in the Light List do not contain latitude and longitude coordinates Note also that a given chart may omit buoys and other information which are shown on a larger scale chart of the area Symbols Q There are numerous charting symbols used to depict buoys of various types Figure 5 5 taken from Chart No 1 provides a sample for review Chart No 1 should be studied in some detail to ensure familiarity with the various buoy symbols Refer to table 5 2 for guidance on the significance of lateral aids Definiti
7. DO NOT USE BUOYS TO PLOT A FIX Emphasis in original SAn articulated light see main text is a buoyant structure tethered directly to the seabed in such a manner that it has no watch circle Although similar to a buoy in some respects it is regarded as a fixed ATON for charting purposes However these should be treated as floating aids in terms of position fixing Aids to Navigation 5 19 Buoys could be off station at any time but are more likely to be off station after storms and in icy conditions During the severe flood ing of the Midwest in the summer of 1993 for example it was estimated Professional Mari ner Issue No 3 that as many as 70 percent of the thousands of ATONs in the area needed to be replaced Severe ice and snow storms in the Northeast in the following year also re quired numerous buoys to be reset in the Dela ware Bay and New York harbor It is recognized that there are circum stances where fixed ATONs may not be avail able for position fixing yet numerous buoys might be present in the area Any position based solely on buoys should be regarded with a healthy skepticism and verified using fixed ATONs at the first opportunity Buoys can be damaged and moved off station by ice one ofthe reasons that position fixing with buoys is notrecommended Here crew from the USCG Red Oak work onan ice damaged buoy Official U S CoastGuard photograph 5 20 NOAA Chart User s Manual
8. Portland ME 1986 Dahl N The Yacht Navigator s Handbook Hearst Books New York NY 1983 National Imagery and Mapping Agency Ameri can Practical Navigator An Epitome of Navi gation Bowditch Publication No 9 NIMA Stock No NV PUB 9 V1 Bethesda MD 1984 National Imagery and Mapping Agency Radionavigation Aids RAPUB 117 Bethesda MD Annual de Gast R The Lighthouses of the Chesapeake The Johns Hopkins University Press Bal timore MD 1993 Dutton s Navigation and Piloting Fourteenth Edition Naval Institute Press Annapolis MD 1985 Eyges L The Practical Pilot Coastal Naviga tion by Eye Intuition and Common Sense International Marine Publishing Camden ME 1989 Hobbs R R Marine Navigation Piloting and Celestial and Electronic Navigation Third Edition Naval Institute Press Annapolis MD 1990 Holland F R Jr America s Lighthouses An Illustrated History Dover Publications New York NY 1981 Human Technology Inc Desk Reference Guide Specifications Unit Chart and Map Fea ture Buoy Report developed for National Ocean Service Charting and Geodetic Ser vices Marine Chart Branch Under Con tract OPM 85 77 McLean VA October 1985 Daybeacon Light Marker Obscured Sector Range Line Riprap Ihnat D J CDR U S Coast Guard Quarterly Report of Short Range Aids to Navigation Commandant G
9. detail Where possible the flare orientation is aligned with those of neighboring buoy sym bols see below Leading lights i e those ar ranged similar to range lights except that only a single light is used to indicate a path to be followed may be charted with the flare oriented seaward along the line Labels and Notes The label and note s provide information on the name of the light and the light s char acteristics including the light number if any This information is very useful for identifying the light and for determining whether it can be seen from the vessel s approximate posi tion i i TEE basn E i i 2e a f r ala FE F hb hp p Miah Maull shoal lightin Delaware Bay Official U S CoastGuard photograph If the name of the light appears in the Light List and space permits the name of the light is shown in black conventional vertical type above the light characteristics The name may be omitted if it is the same as the name of the geographic feature in the immediate vicinity and space is at a premium Thus for example if the geographic name Pt Judith were shown in the chart the name Pt Judith Lt would not be given The characteristics of the light include its flash characteristic color period height vis ibility nominal range and number Flash characteristics include the sequence and timing of the flashes and include fixed occulting single occulting group occult
10. for red N for nun and the num ber of the buoy e g 6 in quotation marks If lighted this buoy would have a somewhat different physical appearance e g a larger buoy rather than the simple nun a red light atop the buoy and would be charted by add ing the magenta disc and the characteristics of the light would be noted as discussed above Unlighted green buoys have a cylindrical shape called a can and bear odd numbers in creasing from seaward These would be charted using the first of the symbols shown in Section Q 2 Q 21 of Chart No 1 and carry the label G for green C for can and the number of the buoy e g 7 in quotation marks If lighted this buoy would have a some what different physical appearance e g a larger buoy rather than the simple can a green light atop the buoy and would be charted by adding the magenta disc and the characteristics of the light would be noted as discussed above Incidentally mariners are sometimes con fused by the exact meaning of the phrase re turning from seaward in certain instances The nautical chart should always be consulted to verify the safe side for passing any buoy with lateral significance Additionally it is worth noting that no buoy should be passed very close aboard buoys can move throughout the watch circle endangering the vessel More over buoys may be located outside of the chan nel generally noted in the Light List in ca
11. removed For details see the U S Coast Guard Light List Lights According to official charting definitions in the Desk Reference Guide a light is a luminous signal emitted by a fixed structure to aid navigation that marks channels warns of dangers or obstruc tions to navigation and assists the mariner in determining his position Lights are identified by their charac teristics at night and by the shape and color of their daymarks Light charac teristics include flash sequence length of light and dark periods color and range of visibility Lights are catego rized by function e g junction light directional light range light leading light sector light passing light and aeronautical light Emphasis added There were approximately 12 200 federally maintained lights in U S waters in 1993 Most lighted ATONs including lights and lighted buoys are equipped with controls that automatically cause the light to operate dur ing darkness and to be extinguished during daylight These devices are not of equal sensi tivity and in consequence all lights do not come on or go off at the same time The light ing apparatus is serviced at periodic intervals but there is always the possibility that the light is extinguished or operating improperly Lights can be used for navigation during the hours of daylight or darkness During day light the fixed structures associated with these lights serve as andmarks
12. 1 following the flash characteristics of the light Generally white lights are not so labeled and if no color is shown on the chart white can be assumed except where a light exhibits more than one color in which case W is shown Amber lights are charted as yellow and abbreviated Y Although the color of a light is important to its identification mariners should be aware that the apparent color of the light may change with distance because the various colored lights may have different nominal ranges see below Additionally ice or snow may cover the panes of unattended lights greatly reducing the visibility of lights see below and may cause colored lights to ap pear white The period of a light is defined as the time in seconds required to exhibit a full pattern together with the interval between patterns Periods are shown on the nautical chart to the nearest tenth of a second expressed as a decimal after the flash characteristic Mari ners should time a light using a stopwatch To increase the precision of measurement for lights with short periods the aggregate time required to complete several cycles should be measured Thus for example if 60 seconds were required for 10 cycles the period would be 6 seconds Taken together the flash characteristic color and period provide key information nec essary to identify the light when it is in opera tion According to both the Admiralty Manual of Navigati
13. 16 NOAA Chart User s Manual Fourteen Foot Bank Light White tower and dwelling on black cylindri cal pile Miah Maull Shoal Light Red conical tower on gray conical pier red cylin drical watch room and black lantern Elbow of Cross Ledge Light Red skel eton tower with small white house on international orange cylindrical base Ship John Shoal Light Brown octago nal dwelling with pyramidal roof on cylindrical pier Light has red sector from 138 degrees to 321 5 degrees cov ers shoals on east channel High inten sity beam down Miah Maul Range Additionally the Light List provides spe cific information on ATONs which are sea sonal information not shown on the nautical chart For example this same volume of the Light List notes that the Deadman Shoal Lighted Buoy IDS which is normally equipped with a flashing green light with a 4 second period is replaced by an unlighted winter marker from December 15 to April 1 of each year The U S Coast Pilot The U S Coast Pilot also provides infor mation on lights and other ATONs The scope of the material provided in the U S Coast Pi lot is quite broad see other chapters of this manual and as a result coverage of ATONs is less complete than can be found in the Light List Nonetheless the U S Coast Pilot does contain useful information on selected ATONSs In particular the U S Coast Pilot often pro vides descriptions of lights that are useful
14. NSR 1 quarter ending 31 March 1993 Data updated to January 1994 with personal communication Lt Mike Peterson USCG Maloney E S Chapman Piloting 60th Edition Hearst Marine Books New York NY 1991 Maxim L D Advanced Coastal Navigation Second Edition United States Coast Guard Auxiliary Coast Guard Auxiliary National Board Inc Washington DC 1990 Mellor J Zhe Art of Pilotage Sheridan House Dobbs Ferry NY 1990 Milligan J E Zhe Amateur Pilot Cornell Mari time Press Centreville MD 1982 Ministry of Defence Directorate of Naval War fare BR 45 1 Admiralty Manual of Navi gation Vol 1 Her Majesty s Stationary Of fice London UK 1987 Moody A B Navigation Afloat Van Nostrand Reinhold New York NY 1980 Naish J Seamarks Their History and Devel opment Stanford Maritime London UK 1985 5 38 NOAA Chart User s Manual Schlereth H Commonsense Coastal Navi gation W W Norton Co New York NY 1982 U S Department of Commerce National Oceanic and Atmospheric Administra tion National Ocean Service and De partment of Defense National Imagery and Mapping Agency Chart No 1 United States of America Nautical Chart Sym bols Abbreviations and Terms Ninth Edi tion Washington DC January 1990 U S Department of Commerce Coast and Geodetic Survey Nautical Chart Manual Volume One Policies and Pro cedures Seventh Edition Washington DC 1992
15. an aural null in rotat ing the antenna to determine the bearing to the station Charting Practices All marine radiobeacons transmitting sig nals in areas where hydrography and other navigational information is provided are charted The useful range of the radiobeacon along with other pertinent information for radiobeacons in U S waters is provided in the Light List On charts of scale 1 500 000 and smaller radiobeacons are not shown if the chart does not permit navigation within their range Low power radiobeacons with a use ful range of 10 miles or less are normally omit ted from small scale charts where larger scale charts are available This section provides information on chart ing practices for radiobeacons and related in formation Charting conventions consist of a radiobeacon symbol and associated label s Symbol S 1 Most radiobeacons are collocated with an other visual aid to navigation If so the chart symbol will include that for the co located aid together with a radiobeacon symbol see Sec tion S 1 of Chart No 1 consisting of a 7 1 mm diameter magenta circle centered on the po sition of the aid For stand alone radiobeacons the black position accurate landmark sym bol see Chapter 6 is placed at the center of the magenta circle Labels In addition to providing information about the host aid e g buoy light etc if one ex ists the label provides information about the
16. caution to alert mariners to the existence of the range light structure when approaching the light from its dark side at night Not all ranges are equipped with passing lights how ever Because the passing light is of second ary importance to the range light its charac teristic is charted on a separate line below the range light label in the same order as shown in the Light List If the visibility of the pass ing light is included in the Light List it is also included in the chart label Symbol M 1 The range symbol is shown in Section M 1 of Chart No 1 The usable portion of ranges is shown by a solid line to the point where the vessel should leave the range Defining the limits of the range is obviously of key impor tance for curving channels From the point where the range should be left the range is continued with a short dashed line to the rear navigational aid In the event of extreme shoaling or shoal ing over a large area in an improved channel range lines may be dashed or even omitted through a shoaling area that is depicted by hy drography Figure 5 8 shows ranges used to mark a section of the upper Delaware River as shown on NOS Chart 12314 Delaware River Phila delphia PA to Trenton NJ Range Labels The range label shows the name of the range and the bearing of the range in degrees true along the range in the direction of the front marker if these are published in the Light List and cons
17. descriptions and photographs which are useful to the mariner Books on lighthouses e g Caldwell de Gast Holland in particular often contain photographs which facilitate daylight identification These books are not designed for navigational purposes however and the appearance of the light may have changed since the photograph was taken Aids to Navigation 5 17 A buoy marking a hazard to navigation may be classified according to the na ture of the hazard as obstruction wreck telegraph cable fish net dredg Buoys According to the somewhat lengthy of ficial definition in the Desk Reference Guide a buoy is a floating object other than a lightship moored or anchored to the bottom as an aid to navigation Buoys may be classified according to shape as spar cylindrical or can conical nun spherical barrel or pillar buoy They may also be classified according to the color scheme as a red green or check ered buoy A buoy fitted with a charac teristic shape at the top to aid in its identification is called a topmark buoy A sound buoy is one equipped with a characteristic sound signal and may be further classified according to the man ner in which the sound is produced as a bell gong horn trumpet or whistle buoy A lighted buoy is one with a light having definite characteristics for de tection and identification during dark ness If the light is produced by gas it may be called a gas buoy
18. gt Q Abbreviation Period shown International i E Oc 2 Gp Occ ATT Oc 2 3 Oc 2 3 con Example 10 3 Iso E Int isophase Flashing total duration of light shorter than total duration of darkness FI 3 10 4 FI 2 Gp FI Group flashing Example FI 2 1 FI 2 1 Composite group flashing Example Long flashing 10 5 LFI L FI flash 2s or longer Q Qk FI AWII DU Ny Continuous quick Q 3 10 6 EN Q 3 Group quick Example IQs Int Qk Fi e Source ChartNo 1 IQ Int Qk Fl Qk FI Interrupted quick wood w 4 Ny Fig 5 2 Illustative Hash Charactenstics Continued on next page NOAA Chart User s Manual Abbreviation International National Class of light it pe VQ V Qk FI Continuous very quick va 3 Group very quick Interrupted very quick je UQ Continuous ultra quick o IUQ interrupted ultra quick Mo A Morse Code F FI Fixed and flashing O weather meteorological visibility of 10 nauti cal miles without regard for the height of the light or the observer For those lights with two or more colors see below either both nomi nal ranges are shown e g 15 10M or the lesser of the two ranges will be given Calculation procedures for estimating the actual distance from which a light can be seen at night considering the height of the light and o
19. pipe structure that oscillates around a uni versal coupling connected to a sinker The light structure which is typically 10 feet to 15 feet above the water surface at high tide is kept upright by the buoyancy of a submerged floata tion chamber Unlike other buoys see below it has no scope of chain and the light is di rectly over the sinker i e this structure has no watch circle It is designed primarily to mark narrow channels with greater precision than conventional buoys in situations where the depth of water up to 60 feet is too great for a normal pile or dolphin light structure see Dutton When first introduced this type of ATON which is neither a true buoy nor exactly a fixed light required a new symbol for charting see Section P 5 of Chart No 1 This symbol is a black open circle 1 0 mm in diameter the ap proximate position symbol for a landmark ex plained in Chapter 6 centered on the pub lished position with a magenta flare The open circle is chosen in lieu of a dot used for other fixed lights because the structure may be dis placed more than 10 feet of its true position The articulated light is labeled Art in New ton Medium italic type Strobe Lights Many charted features are marked with very quick flashing high intensity lights called strobe lights The light is usually a xe non gas condenser discharge flash lamp or flash tube Strobe lights are used on certain
20. radiobeacon The label is given in black verti cal type if the antenna is attached to a fixed aid and italic type if the antenna is attached to a floating aid Aids to Navigation 5 35 Miscellaneous Related Information The label includes the abbreviation R Bn the frequency in kilohertz and the Morse code characteristics regardless of the chart scale Aeronautical Radiobeacons Aeronautical radiobeacons which operate on similar frequencies to marine radiobeacons and can be received by the same equipment are sometimes useful for marine navigation particularly if located in close proximity to the coastline or if there is no rough terrain be tween the beacons and the coastline that might distort signal propagation If charted the aeronautical radiobeacon is depicted with a black position accurate land mark symbol and a 7 1 mm diameter magenta circle centered on the landmark symbol A la bel in conventional black type is placed adja cent to the symbol and clear of the magenta circle The label includes the abbreviation AERO R Bn and the frequency and charac teristics of the radiobeacon 121 Beacons marking a clearing line 12a j MARKERS bearings MARKERS 123 124 Refuge beacon Cable landing beacon example Nautical charts also include information on courses recommended and alternate courses routing systems traffic schemes and areas and limits These are discussed
21. sound by com pressed air emitted through a circum ferential slot into a cylindrical bell chamber Bells produce a distinctive sound by the vibration of a hollow cup shaped metallic vessel which gives forth a ring ing sound when struck Gongs produce a sound by the vibra tion of a resonant disc There were approximately 1 620 fog sig nals on federally maintained ATONs in 1993 the majority 75 percent of which were in stalled on buoys These fog signals are used by the mariner in much the same manner as lights or buoys And indeed these signals are often collocated with fixed or floating aids to navigation Each Aids to Navigation fog signal has specific characteristics by which it can be distinguished The signal character istic is the phase relationship of the recurring sound emissions Here are a few pointers to keep in mind relative to fog signals and op eration in fog 5 27 Particular attention should be paid to positive identification of buoys in sequence When a buoy in sequence is missed consider running a search pattern to find the buoy Moreover use all available means Fog signals on fixed stations and large navigational buoys produce a specific number of blasts and silent periods each minute when operat ing to facilitate positive identifica tion Fog signals on buoys are generally activated by the motion of the sea therefore they do not emit regular signal characteristics an
22. that are moored to the seabed by concrete sink ers attached to the body of the buoy with chain or synthetic rope of various lengths Buoy moorings vary in length being suffi ciently long to accommodate the water depth where the buoy is located plus an allowance for variations in water depth The mooring lengths define a watch circle and buoys move within this circle depending upon wind current and tidal height The size of the watch circle is not reflected in the chart 7As an example of this point an attractively illustrated book see de Gast reprinted in 1993 contains a dramatic photograph of the Sharps Island Light referred to above This light correctly described in the USCG Light List is leaning as a result of ice damage in 1977 The photograph of this light unchanged since the original 1973 edition of this book does not reflect this damage No doubt the light looks better in its undamaged state and the author did not intend to write a navigation text 5 18 NOAA Chart User s Manual More than 80 percent of buoys in U S waters are unlighted Unlighted nun buoy Official U S Coast Guard photograph Buoys vary substantially in size and physi cal appearance The reader is directed to any of several references at the end of this chap ter for illustrations and photographs of vari ous types of buoys A Brief Digression Position Fixing with Buoys It is noted above that ATONs can be used for fix
23. Aids to Navigation 5 1 CHAPTER 5 An incorrectly identified mark is a hazard not an aid to navigation Alton B Moody Aids to Navigation Introduction and Overview According to accepted NOAA Nautical Chart Manua nomenclature an Aid to Navi gation ATON is a man made structure device exter nal to a craft designed to assist in de termining the craft s position or a safe course or to warn of dangers or obstruc tions When the information is transmit ted by light waves the device is a visual aid to navigation if by sound waves an audible aid to navigation if by radio waves a radio aid to navigation Any aid to navigation using electronic equip ment whether or not radio waves are involved may be considered an elec tronic aid to navigation The term aid to navigation should not be confused with the more general term naviga tional aid which covers any instrument device chart method etc intended to assist in the navigation of a craft A more complete list of ATONs and associated information normally found on nautical charts is provided later in this chapter Briefly how ever ATONs include such objects as buoys lights fog signals daybeacons range markers radiobeacons and LORAN C and Omega lat tices Although the GPS certainly satisfies the definition of an ATON this system is not dis cussed in this chapter because GPS informa tion is not provided on nautical ch
24. USCG maintained ATONs and on aeronauti cal hazards such as stacks towers and build ings ATONs published in the NM and Light List as well as landmarks with a strobe light include the label Strobe as well as other la bel elements see above The flash period of a strobe light is usually but not always omit ted because of its extremely short duration much less than 1 second The reason italics are used in lieu of the vertical lettering found on other lights is that articulated lights though classified as fixed structures are floating lights Buoys are also labeled in italic type Aids to Navigation 9 15 Riprap Riprap are mounds of broken rock cobbles boulders or fragments that are often placed around light structures as protection against ice damage and scouring by fast moving cur rents Desirable as the use of riprap may be from the point of view of protecting the struc ture and helping to ensure the reliability of the light triprap also presents a hazard to navigation for vessels that pass too close aboard Riprap is denoted on nautical charts by a special symbol see Section P a of Chart No 1 Supplemental Information Regarding Lights and Other ATONs In addition to the nautical chart the Light List the U S Coast Pilot and commercial cruising guides offer relevant information on ATONs Additional information provided in these sources is briefly discussed below The Light List The L
25. arboar lateralmarkasfollows Charactenstc Color Sha pe buoys Daymark Preferred Channel to Starboard Green with one broad red honzon talband Cylindncal can orpillar Green guare lowerhalfred Prefened Channel to Port Red with one broad green hornzontalband Conical nun orpillar Red tnangle lowerhalfgreen Color Green Rhythm Reflectorcolor Green Composte group flashing 2 1 Red Composte group flashing 2 1 Red CAUTION When proceeding toward sa itmay notalwaysbe possible to passon eitherside of preferred channelaidsto navigation The appropnate nauticalchartshould alwaysbe consulted in the Light List will also be found on the chart Additionally some ATONs are charted which are not in the Light List such as those estab lished by neighboring foreign countries aids having reliable maintenance authorities such as those established by the military and environmental buoys which are not included in the Light List As well radar reflectors lights and sound signals are charted for those features e g floats targets platforms dredg ing range markers and data collection buoys not specifically intended for use in navigation whether the feature is listed in the Light List or not This assumes that the chart has been corrected based upon data in the LNM 5 6 NOAA Chart User s Manual ATON information provided on nautical charts includes a symbol unique to each class
26. arning daybeacons There were approximately 11 900 federally maintained daybeacons in U S waters in 1993 less than one half the number of buoys Daybeacons are often used in shallow inland waters because these are less expensive to in stall and maintain than buoys Additionally these have the advantage of being fixed rather than floating structures Physically these con sist of one or more piles driven into the bot tom surmounted by signboards called daymarks Charting Practices This section provides information on chart ing practices for daybeacons and related in formation Charting conventions consist of a symbol and associated abels to describe the characteristics of the daybeacon Daybeacon Symbols The daybeacon symbols are shown in Sec tion Q 80 through 83 of Chart No 1 The cen ter of the daybeacon symbol is located at its geographic position Daybeacons along dredged channels are also charted in their true positions unless they are on opposite sides of a channel and plot less than 0 5 mm apart In this case to add clarity the aids may be separated to 0 5 mm However daybeacons are not moved off ranges see below nor natu ral objects There are two principal standard symbols used to depict daybeacons a triangle and a square Triangular daybeacons starboard hand red marks with even numbers in the IALA B system are typically represented by an equilateral triangle 2 0 mm on each side To avo
27. arts Omega is also not discussed in this manual even though Omega information is provided on cer tain nautical charts because small craft are not generally equipped with these receivers Fi nally charted LORAN C information is not in cluded in this manual because this is covered at length in the USCG LORAN C User Hand book to which the reader is referred ATONs may be fixed land based or fixed structures in the water or floating e g buoys Landmarks are the functional equiva lent of ATONs but because these have not been especially constructed for this purpose are not formally classified as ATONs Land marks are treated in a separate chapter Chapter 6 Landmarks of this manual This chapter provides information on the type and utility of ATONs and how these are depicted on nautical charts Because ATONs are so important to safe navigation and there fore charted in great detail this chapter is long and detailed The chapter also identifies the sources of additional information e g the Chart No 1 U S Coast Pilot and the Light List which supplement that provided on the nauti cal chart As appropriate practical comments are made throughout the chapter on the correct use of ATONs for marine navigation See also 5 2 NOAA Chart User s Manual Chapter 6 for additional perspectives applicable to ATONs as well as landmarks Numerous ref erences are given at the end of this chapter for those interested in ad
28. ating from about 1500 A D shows buoys as well as towers A seaman s manual of 1295 A D refers to buoys marking the river channels to Seville In England Trinity House was established in the early 1500s as a pilotage authority charged with among other things the responsibility of constructing and maintaining marks on the land By the 1700s ATONs had become relatively sophisticated and widespread The first re corded range marks in America were two light towers placed in line on Plumb Island to mark the channel to Newburyport MA on the Merrimack River Importance of ATONs in Coastal Navigation As with landmarks ATONs are charted ob jects used for determining ZOP e g with a hand bearing compass or radar or by direct plotting in the case of range markers and curves of position e g circles of position with an optical range finder for ATONs with charted height information such as certain lights or hy perbolas of position with LORAN C so as to determine a fix or estimated position for the vessel ATONs also mark hazards to navigation identify the limits to safe channels designate special use areas quarantine and anchorages and provide other relevant information Table 5 1 provides both general and specific illustra tions of how information derived from ATONs can be used for marine navigation ATONs can be used to fix the vessel s position to serve as homing or tracking aids to ensure that the ves sel remains
29. avigation Whenever observations are taken on any fixed ATON or landmark this information should be plotted on the nautical chart by the mariner Even a single LOP can be useful and fre quent fixes are typically necessary in coastal waters where ATONS are placed Differences between the vessel s dead reckoning position and the plotted fix enable currents to be estimated and or should alert the mariner to the possibility of other errors Finally all available means e g maintenance of a dead reckoning plot use of GPS LORAN C depth sounder or other means should be 5 3 5 4 NOAA Chart User s Manual used for navigation Reliance on only one method is unprofessional and unwise ATONs and Related Chart Information General This chapter includes the following ATONs lights buoys fog signals daybeacons ranges and radiobeacons These are discussed in order in the following sections Brief com ments on trial courses are also included in this chapter The symbols used in charting these aids are illustrated in Sections P Q R and S of Chart No 1 Nautical Chart Symbols Abbreviations and Terms Ninth Ed to which the reader is referred Pertinent excerpts from Chart No 1 are included in this chapter for ready reference ATONs are placed in appropriate locations in harbors and inland waterways to facilitate navigation The placement of these ATONs fol low a particular pattern or convention ter
30. bserver nominal range and prevailing visibility are detailed in the Light List and other references e g Bowditch Dutton Maxim Common practice for the navigator is to draw circles around these lights on the chart with radius equal to the distance at which the light is likely to be visible see Schlereth and to estimate the correspond ing time when these should first be seen lllustration Very quick repetition rate of 80 to 159 usually either 100 or 120 flashes per min Ultra quick repetition rate of 160 or more usually 240 to 300 flashes per min bdddiddidddddkkddddd dkiddik ddkidid d kiidddkdd ddd d dikididddddti k kit didididiiiiiiti dddddddiiddiiitakdikdiiidiiiii a Vaala Rn ml Source Chart No 1 Continued Fig 5 2 Illustrative Hash Charactenstics Period shown 1 VQ V Qk FI ying ny abdddddaddddiikitiddddddddkihi These calculations are only approximate Burch Nonetheless if lights are not sighted within a reasonable time after that predicted a dangerous situation may exist and the mari ner should be appropriately cautious Finally the assigned number or letter s of the light structure if any are shown fol lowing the visibility and enclosed in quota tion marks The number or letter can be ob served e g with binoculars during daylight hours On large scale charts the characteristics of lights are shown in the following order flas
31. cally these can be lighted with a white light blinking the Morse A or un lighted with either the characteristic shape of the lighted buoy or a spherical shape These are vertically striped red and white These are charted by the first of the symbols shown in Section Q 5 of Chart No 1 with or without the magenta disc depending upon whether the buoy is lighted or not The label would con tain the color code RW for red and white and the identifying letter on the buoy together with the light characteristic Mo A if appro priate Fog Signals R According to official charting definitions in the Nautical Chart Manual fog signals are audible aids used to warn of danger and to provide the mariner with a means of determining a craft s position when vis ibility is obscured by fog snow rain smoke or thick weather Among the de vices in common use as fog signals are the following Diaphones produce sound by means of a slotted reciprocating piston actuated by compressed air Two tone blasts consist of two tones of different pitch beginning with a high pitched blast and ending on a low pitch Diaphragm horns produce sound by means of a disc diaphragm vibrated by compressed air or electricity Duplex or triplex horn units of differing pitch produce a chime signal Sirens produce sound by means of ei ther a disk or a cup shaped rotor actu ated by compressed air or electricity Whistles produce
32. clear of dangerous waters e g by using danger bearings danger circles or pass ing on the safe side of buoys to identify turn points and for a variety of specialized purposes such as compass calibration or less frequently with ATONs to determine whether or not the vessel s anchor is dragging Importance of Positive Identification and Related Matters Before discussing the various types of ATONSs charting practices and related mat ters it is appropriate to emphasize several key points noted throughout this manual The mariner should be fully famil iar with the charting conventions employed to depict ATONs And im portant textual material e g Chart No 1 and the appropriate USCG Light List should be readily avail able for reference Any observed ATON or landmark should be positively identified by the mariner prior to its use for naviga tion Published texts e g Cahill Aids to Navigation Table 5 1 Utility of ATONs Shown on Nautical Chart GENERAL e Used fordetermining range orbeanng by visualmeans orradar incoastalwatersso asto determine a fixorestimated postion SPECIFIC ILLUSTRATIONS Used fordetemination of fix running fix estimated postion stand drift of curent Used forplotting dangerbeanngs dangercircles honzontaldangerangles Used in conjunction with dangerbeaning orcircle forevaluation of vessel spostion with resoectto unobservable hazardsto navigation Used to d
33. d when the sea is calm may emit no sound signals Fog signals can be activated by sev eral means including manually re motely or with a fog detector In cases where a fog detector is em ployed there may be a delay in the automatic activation of the signal Additionally fog detectors may not be capable of detecting patchy fog conditions The sound from a fog signal may not be sufficiently loud to be heard over the noise of an engine Therefore it may be useful to periodically re duce the engine to idle power or turn it off completely to listen for these signals Remember to sound the appropri ate signals when operating in fog If visibility is so impaired to neces sitate reliance on fog signals it is sufficiently poor to require appro priate sound signals from all ves sels Note also that speed should also be adjusted to the prevailing circumstances of navigation including electronic position finding aids radar and depth sounder information Finally as noted in the Light List mariners should not rely on sound signals to determine their position Distance cannot be accu rately determined by sound inten sity Occasionally sound signals may not be heard in areas close to their location Signals may not sound in cases where fog exists close to but not at the location of the sound signal These important caveats aside fog signals can be very useful aids to navigation in cir cumsta
34. ditional detail Names enclosed in parentheses e g Bowditch denote particularly pertinent references The Glossary in appendix A provides definitions of key terms related to ATONs Brief Historical Asides As might be expected what are now called ATONs have a long history see e g Bowditch Naish As the later history of ATONs may be familiar to readers of this manual it is interesting to provide some brief asides on the early periods Towers used originally as landmarks and later as light houses were reportedly constructed to aid passage along the Mediterranean coast as early as 660 B C Between 283 and 277 B C Sostratus of Cnidus built a large 500 ft struc ture on the island of Pharos which marked the harbor of Alexandria from the north The Romans established a network of fire towers along the Mediterranean By medieval times beacons and range mark ers were in use to facilitate entrance to the ports of Genoa and Pisa In the so called Dark Ages in Europe hermits and monks located on remote islands and promontories displayed light signals in chapels and participated in salvage operations for wrecked vessels Today this might be viewed as a conflict of interest The organization of the Hanseatic League not only provided for economic cooperation but also advanced the use of ATONs and mechanisms for collecting what would now be termed user fees for navigation A surviving chart of the ap proaches to Bruge d
35. e complete familiarity with this important topic Unlike many of the other objects or features depicted on the chart ATONs are deliberately placed so as to optimize information provided to the mariner Because the cost of establish ment and periodic maintenance are sufficiently high ATONs are not casually placed So it is certain that if an ATON has been put in a given place it is because this location has real sig nificance to the mariner Therefore it is par ticularly important that the mariner be famil iar with the uses significance and chart con ventions employed to depict this aid The consequences of poor cartography could be dire During the Napoleonic Wars British losses by shipwreck caused by bad charts as well as bad weather were eight times as great as those inflicted by the enemy Wilford Aids to Navigation 5 37 References Anon Charthouse Chatter Professional Mariner Issue No 3 October November 1993 p 7 Anon Charthouse Chatter Professional Mariner Issue No 4 December Jarnuary 1994 pp 6 7 Brogden W Inside Ranges A Look at What Makes These NAVAIDS so Useful Ocean Navigator Issue No 60 March April 1994 pp 74 et seg Burch D Emergency Navigation Interna tional Marine Publishing Company Camden ME 1986 Cahill R A Strandings and Their Causes Fairplay Publications London UK 1985 Caldwell B Lighthouses of Maine Gannett Books
36. e and the accompanying remarks The description of the structure is particularly useful for identifying lights during daylight conditions For example the route from sea ward up the Delaware Bay is marked by sev eral lighthouses including the Brandywine Shoal Light see figure 5 4 Fourteen Foot Bank Light Miah Maull Shoal Light Elbow of Cross Ledge Light and Ship John Shoal Light Photographs in this chapter show two of these lights Mariners with local knowledge can readily identify these lights by their distinc tive physical appearance However those without local knowledge would certainly ben efit from the following descriptions taken from the Light List Volume II Atlantic Coast Toms River New Jersey to Little River South Caro lina 1993 Brandywine Shoal Light Cylindrical concrete structure adjacent to old screwpile with red sector from 151 de grees to 338 degrees covering shoal area southwest of Cape May As with several other lights in the area this light is equipped with an emergency light of lower intensity with same char acteristic as main light when main light is extinguished In SAR cases on the Delaware Bay in which the distressed mariner reports a position near one of these lights rescue authorities often ask the mariner to describe the light This procedure can save fruitless search hours in cases where the distressed vessel does not have an accurate position fix and misidentifies the light 5
37. eing emitted by the shore station relative to the ves sel The basic value of the radiobeacon sys tem lies in its simplicity of operation and its relatively low user costs even though the results obtained may be somewhat limited The general problems and prac tices of navigation when using Aids to Navigation 9 33 greater than 50 miles a correction is usually applied to the bearing before plotting on a Mercator chart These cor rections as well as information on ac curacy of bearings plotting and other matters are contained in Radio Navi gation Aids jor the U S Coast Pilot radiobeacons are very similar to those encountered when using visual bearings of lighthouses or other charted objects A radiobeacon is basically a short range navigational aid with ranges from 10 to 175 nautical miles Although bearings can be obtained at greater ranges they will be of doubtful accu racy and should be used with caution When the distance to a radiobeacon is An individual radiobeacon can be used to determine a single LOP and for tracking or homing purposes If the vessel makes a 90 dog leg of known length the approximate WARNING The prudent mariner will not rely solely on any single aid to navigation particularly on floating aids See U S Coast Guard Light List and U S Coast Pilot for details Pennsbury M State Par ge Oc ee 35tt q Dey wil Y M W SS croft M
38. eral aids to navigation sys tems employing dual beacons which when the structures appear to be in line assist the mariner in maintaining a safe course The appropriate nauti cal chart must be consulted when us ing ranges to determine whether the range marks the centerline of the navi gation channel and also what section of the range may be safely traversed Ranges display rectangular dayboards of various colors and are generally but not always lighted When lighted ranges may display lights of any color As constructed a range consists of two beacons one is called the front range marker and is lower in height than the other called the rear range marker The rear marker is usually located some distance from the front marker Often the front range marker is on a fixed structure in the water and the rear range marker is on land When these two markers appear directly in line one behind the other but both visible because the rear marker is higher they are said to be in range or in transit in British usage The line defined by the range is called a range line or leading line Daybeacons and other charted objects forming a range are often called leading marks Likewise range lights are sometimes termed leading lights Approaching the front range marker if the two marks are exactly in range the vessel s position is exactly along the range line If the lower marker is to the left righ
39. etemine a safe course which avoidsunobservable hazardsto navigation Used forestablishing vesseltuming beanngs Used forhoming ortrac king pupos Used forcompasscalibration and Lessfrequently Used fordetermining whetherornotan anchorisdragging Milligan Maxim and USCG acci dent files are replete with examples of mishaps or accidents which re sulted from the incorrect identifica tion of an ATON Bowditch see ref erences lists failure to identify aids to navigation as the second of 16 common errors in navigation The mere observation of an ATON or landmark at approximately the right position and at approximately the right time although relevant is not sufficient proof that the aid ob served is the same as that shown on the chart ATONs are equipped with numerous characteristics e g the flash characteristics and color of a light the Morse code identifier of a radiobeacon the number and color of an unlighted buoy or daybeacon to facilitate positive identification Closely related to the above point it is important that charts and such publications as the Light List and U S Coast Pilot be amended as de scribed in the atest published cor rections ATONs are moved renum bered removed and or characteris tics changed periodically This can have significant consequences see Cahill for the uninformed mariner Bowditch also lists failure to cor rect charts among the common er rors in n
40. f the obscured sec tor Additionally a dashed arc in the sector centered on the light indicates the obscured sector Directional arrows are used to mark the points where the dashed arc intersects the dashed ray line A label LT OBSC or DARK SECTOR is added for clarity See figure 5 3 for an illustration of a light with an observed sector taken from NOS Chart No 13218 In other cases sectors are deliberately cre ated by placing colored glass in the lanterns of lights to provide additional information to the mariner Sector lights see Sections P 40 and 42 of Chart No 1 for symbology are used primarily to warn mariners of dangerous shoals or other hazards to surface navigation The danger sectors are usually red and are charted in degrees true from the perspective of the mariner looking toward the light Mari ners are cautioned not to alter course based solely on the observed sectors but rather to note the correct compass bearing This is be cause it is difficult to determine the sector boundaries with accuracy because the edges of a colored sector cannot be sharply demar cated Figure 5 4 presents an excerpt from NOS Chart No 12304 which shows a red sector on the Brandywine Shoals Light warning of shoals in this area Directional Lights Several types of directional lights are in use see Section P 30 of Chart No 1 for chart con ventions These lights have a very narrow sec tor designed to mark a directi
41. for identifying the light structure during daylight hours For example here are a few descrip tions of lights taken from the U S Coast Pilot Volume 3 1993 Atlantic Coast Sandy Hook to Cape Henry The entrance to South River is be tween Saunders Point and Thomas Point 1 8 miles northeastward Thomas Point Shoal Light 38 53 9 N 76 26 2 W 43 feet above the water is shown from a white hex agonal tower on piles in depths of 5 feet near the outer end of the shoal 1 2 miles east southeastward of the point a fog signal is at the light The light is 1 5 miles due west of a point on the bay ship channel 124 2 miles above the Capes p 176 Solomons Lump Light 38 02 9 N 76 00 9 W 47 feet above the wa ter is shown from a white octago nal dwelling with a square tower on a brown cylindrical base in depths of 7 feet on the Smith Island side of Kedges Straits p 190 Sharps Island Light 38 38 3 N 76 22 5 W 54 feet above the wa ter is shown from a leaning brown tower on a cylindrical pier in 10 feet at the north end of a shoal that bares at the east end p 194 This description is particularly valuable to those without local knowledge The structure actually leans a great deal and it is difficult to believe that this is an ATON when approaching from certain angles in daylight Published Guides and Other Books Published cruising guides and other books often have
42. for bearing or range determination During daylight hours the identification of the light is based upon the position of the light and its physical appearance The physical appearance of a Lighted buoys are classified by NOAA as buoys rather than lights and are discussed later in the main text Aids to Navigation 5 7 light structure is not found on the chart how ever as noted below At night the light is used in much the same manner except that the identification of the light is based primarily upon the characteristics of the light such as the color flash sequence and position Charting Practices This section provides information on chart ing practices for lights and related informa tion Charting conventions consist of a light symbol associated abels and notes and for sectored lights or where lights have obscured sectors information on the sector s Symbol P Major lights minor lights and lighthouses are charted as shown in Section P of Chart No l In particular the position of the light is shown by a black 0 75 mm dot or open black circle 1 0 mm in diameter in the case of an ar ticulated light with a magenta flare 3 4 mm in length with a rounded end of 0 6 mm ra dius drawn about 1 mm from the light dot This light symbo has the visual appearance of an exclamation mark in print The flare is generally oriented toward the label and is drawn to avoid obscuring other relevant chart
43. h Dutton Hobbs For many years this system also called ra dio direction finder RDF had the largest num ber of users of any radionavigation system In recent years LORAN C and GPS have become systems of choice for marine navigation How ever many radiobeacons are being modified to broadcast differential GPS corrections so radiobeacons will continue in service for some time to come Marine radiobeacons operate in the 200 to 400 kilohertz region just beneath the AM broadcast band These radiobeacons transmit a Morse code identifier for 50 seconds fol lowed by a 10 second continuous tone at the end of each operating minute The function of the Morse code se quence is to provide positive iden tification of the radiobeacon Posi tive identification of radiobeacons is as important as positive identifi cation of any ATON Morse code identifiers are often but not al ways an abbreviation of the facil ity name Thus for example the two letter Morse code identifier for Cape May is CM and that for Barnegat Inlet is BI However there are exceptions Cape Henry for example carries the identifier CB so it is necessary to consult the Light List for authoritative in formation The Light List provides the Morse symbols e g Cape May is so it is not necessary to know Morse code to use the system The function of the continuous tone is to provide the best signal for de termining
44. h characteristic color period height vis ibility and number For example an 85 foot red light number 2 of nominal range 10 miles which exhibits a group of three flashes within a period of 10 seconds would include Aids to Navigation 5 11 the light symbol light name if appropriate and the label Fl 3 R 10s 85ft 10M 2 Small scale charts show complete informa tion regarding characteristics for major sea coast lights expected to be used for coastal navigation but may omit certain information in cases where congestion is a problem In this event characteristics are omitted in the fol lowing order height period number of flashes in groups the number or letter on the struc ture and the nominal visibility Sectors and Related Matters In some cases terrain masking e g a mountain or island may limit the area over which a light may be seen Knowledge of these blind areas is obviously useful to mariners There is after all no point in looking for something that cannot be seen Moreover a prudent mariner might well alter the in tended track so as to avoid an obscured sector of a major light An obscured sector some times termed dark sector is a portion of the light sector of a navigational light in which the light is not visible Where a LNM reports its establishment the obscured sector see Sec tion P 43 of Chart No 1 is charted with dashed rays marking the limits o
45. he IALA System gt Q 130 IALA System buoy topmarks beacon topmarks shown upright Beacon with topmark color radar reflector and iqnati o No 2 designation i i R Buoy with topmark color radar reflector and designation i No3 Note Radar reflectors on floating marks are usually not charted Fig 5 5 An Excerpt From Chart No 1 Buoys Continued on next page 5 22 NOAA Chart User s Manual Buoys Features Common to Buoys and Beacons gt Q1 11 Shapes of Buoys eo z A Conical buoy nun buoy M a gt O 7 Can or cylindrical buoy MO N nN ao v a sp A Spherical buoy Pillar buoy M D No P e w Spar buoy spindle buoy Super buoy Light Floats 30 a Light float as part of IALA System Ls o f Light float unmanned light vessel not part of IALA System ro Fi 10s12m26M it Mooring Buoys Oil or Gas Installation Buoy gt L Small Craft Mooring gt U D am gt Mooring buoys A A A he Lighted mooring buoy Example Trot mooring buoys with ground tackle and berth numbers Mooring buoy with telegraphic or telephonic communication See Supplementary national symbols S t Numerous moorings example Small Craft Moorings Continued Fig 5 5 An Excerpt Rom Chart No 1 Buoys Aids to Navigation a _ ri 4 e LANBY silhouetted against rising
46. id chart clutter in congested areas a 1 5 mm triangle may be substituted Red tri angular daybeacons are shown with a magenta fill those with other colors e g preferred channel daybeacons are unfilled and the col ors and identifying numbers or letters are in cluded in the label Square daybeacons port hand marks with odd numbers in the IALA B system are typi cally represented by a square 1 65 mm on each side or a smaller 1 3 mm square The square symbol is also used to represent rectangular round octagonal or diamond shaped daybeacons Green daybeacons are shown with a green fill those with other colors e g preferred channel safe water or special pur pose daybeacons are left unfilled and the col ors and identifying numbers or letters are in cluded in the label Figure 5 7 shows daybeacons in the vicin ity of Hereford Inlet New Jersey Daybeacon Labels Labels include the color s of the daybeacon and the identifying numbers and letter s charted in black vertical type Color choices include red starboard hand markers desig nated with an R red and green junction bea cons with preferred channel to port desig nated with an RG red and white fairway beacons designated with an RW green port hand markers designated with a G Note that these are depicted in upright letters rather than italics because these are fixed structures 5 30 rf Q 34 7 Lena
47. idered useful to the mariner Dredging Ranges The USACE has established ranges in some areas to control channel maintenance dredg ing These ranges often unlighted are not in tended for navigation and are charted only as a DREDGING RANGE Structures compris ing this range are charted as landmarks see Chapter 6 If the dredging structure is listed in the Light List the structure label provides light and fog signal information Natural Ranges Spires cupolas towers tanks and other artificial or natural features may form natu ral ranges which chart users sometimes rec ommend for charting These natural ranges are not charted unless recommended by the USCG and published in the LNM Radiobeacons and Related Aids S A brief introduction to radiobeacons pro vided in the Light List states As the first electronic navigation sys tem of navigation radiobeacons pro vided offshore coverage and also be came the first all weather electronic aid to navigation The Coast Guard op erates about 200 radiobeacons located on the Atlantic Gulf and Pacific coasts and on the Great Lakes These radiobeacons are located at light houses on large buoys and along the coasts All positions are charted In order to use this system the mari ner needs a radio direction finder which is a specifically designed radio receiver with a directional antenna This antenna is used to determine the direction of the signal b
48. ifically sis added designated for navigation placed on shore or on marine sites They are es tablished and maintained by the U S Key words in the above definition are bea Coast Guard They are identified by con and fixed Contrary to the popular sense their color and the shape of the of the word beacon daybeacons are un daymark Reflective borders are placed lighted aids Moreover these are fixed struc on certain daybeacons to assist the tures and therefore admonitions against According to Naish see references the word beacon comes from the German word bake The meaning of this word in Frisia and North Germany is a signal pole or construction placed in or near the water The plural form baken is the source of the English word beacon Aids to Navigation 5 29 using floating structures noted in the above section on buoys for position fixing do not apply Daybeacons are used by mariners in the same manner as lights and landmarks e g to identify channels and to fix the vessel s po sition The lack of lighting limits the utility of these aids for night navigation but despite this limitation daybeacons appear surprisingly bright in the reflected glare of the vessel s searchlight Daybeacons include lateral daybeacons in red or green preferred chan nel daybeacons safe water daybeacons in red and white and special purpose daybeacons yellow quarantine area daybeacons regula tory w
49. ight List is the authoritative source of information on ATONs It is published an nually by the USCG in several volumes cov ering various geographic areas The Light List is a valuable complement to the nautical chart and provides specific information on ATONSs Contrary to the implication of its title the Light List offers information on unlighted as well as lighted ATONs In addition to general information regarding ATONs the Light List includes specific information on each ATON such as its LLNR the name and location of the ATON the geographic coordinates latitude and longitude characteristics height nomi nal range for a wider variety of ATONs than found on the nautical chart an identification of the structure and pertinent remarks The organization of the Light List is actu ally quite logical but requires some study to be used effectively When all else fails the index at the back of each volume is helpful Much of the information on ATONs shown in the Light List is identical to that provided on nautical charts However the Light List does contain information not found on charts and additionally is revised more frequently than most nautical charts and therefore is more likely to contain up to date information However a properly corrected chart is also up to date Perhaps the most useful information con tained in the Light List that does not appear in the nautical chart is a brief description of the structur
50. in Chapter 7 Trial courses however are included in this chapter Measured Course Q 122 A trial course is a course at sea the ends of which are marked by ranges ashore and the length of which has been accurately measured Trial courses are used by vessels to calibrate logs and other instruments that measure speed as well as to prepare graphs or tables of engine revolutions per minute RPM ver sus speed through the water See Maxim or other references for details A standard symbol see the excerpt noted in Section Q 122 from Chart No 1 and repro duced here in figure 5 9 is used to mark the range or measured course ashore The course and length of the trial course are indicated by a label Beacons marking measured distance with quoted f 7 Measured Distance 1852 m 090 270 I Ret la Fig 5 9 Thal course symbols shown on Chart No 1 5 36 NOAA Chart User s Manual a mn COAST GUARD iU gt p U S Coast Guard Buoy Tender passing by green lighted radar reflective buoy Angle of buoy suggests cunent is moving from night to left in this photograph Approximately 4 600 lighted buoys mark U S waters Official U S CoastGuard photograph Concluding Remarks As noted this chapter is long and quite de tailed Nonetheless the information pre sented is very important and bears reading preferably with a nautical chart and Chart No 1 readily at hand and rereading to ensur
51. ine Range lights are often visible at distances consider ably greater than the actual usable range to ensure that they can be seen in adverse weather conditions After extensive research and testing the USCG is preparing to install light pipes on many channel ranges around the country Professional Mariner 1994 These light pipes are fiberglass tubes approximately 15 feet long and 6 inches in diameter with a special film on the inside and a light source at one end The light pipe is placed directly in front of the boards of the range markers The light pipes are highly conspicuous at ranges up to several miles and compared to conventional lights it is much easier to detect the alignment or misalignment of two vertical lines of light Light pipes will be supplied with various colors and charac teristics in the same manner as conventional range lights 5 32 NOAA Chart User s Manual Charting Practices Only ranges published in the Light List are charted As with other ATONs charting con ventions consist of a symbol and associated labels Range lights are separately charted as noted above in the section on lights If the scale is too small to chart a pair of range lights in dividually these are shown with one light dot and labeled for example 2F A passing light if installed is generally placed on the front light of a range structure located in the wa ter The passing light serves as an extra pre
52. ing and composite group occulting isophase gt These are shown in conventional rather than italic type because italic type refers among other things to floating structures See also Chapter 4 5 8 NOAA Chart User s Manual flashing including single flashing group flashing composite group flashing quick very quick and ultra quick Morse code e g Morse A fixed and flashing and alternat ing Illustrative flash characteristics and as sociated chart labels are shown in Section P 10 1 to 10 11 of Chart No 1 which is repro duced in figure 5 2 Although not particularly complex this diagram requires some study Study of this illustration should be supple mented with on the water practice in identi fying the characteristics of lights Mariners are also cautioned that if a vessel has consid erable vertical motion due to pitching in heavy seas a light sighted on or near the ho rizon may alternately appear and disappear with the possible result that its true charac teristic will not be apparent In consequence the light could be misidentified Under these conditions the true characteristic may not be apparent until the vessel is closer to the light The watch stander should be placed at the highest convenient station for such observa tion The color of lights is shown using stan dard abbreviation e g R for red G for green W for white etc as shown in Sections P 11 2 through 11 8 of Chart No
53. ing the vessel s position Although it may be common practice to use both fixed and float ing ATONs for this purpose the prudent mari ner should try to avoid fixing the vessel s posi tion using floating aids As noted in the intro ductory material published in each Light List Buoy positions represented on nautical charts are approximate positions only due to the practical limitations of posi tioning and maintaining buoys and their sinkers in precise geographical locations Buoy positions are normally verified during periodic maintenance visits Be tween visits atmospheric and sea condi tions seabed slope and composition and collisions or other accidents may cause buoys to shift from their charted loca tions or cause buoys to be sunk or cap sized Prudent mariners will use bearings or angles trom fixed aids to navi gation and shore objects soundings and various methods of electronic navigation to positively fix their position Empha sis added Guidance on the use of buoys for position fix ing offered in COMDTPUB P16502 8 U S Coast Guard Aids to Navigation p 39 is even more explicit In order for mariners to derive maxi mum use from aids to navigation the different aids to navigation are shown on nautical charts Thus mariners are aware of the aids to navigation which they may expect to pass and may plot any bearings which they take for the purpose of determining their position
54. med the lateral system in which the colors shapes and numbering of lights buoys and daybeacons are determined by their position in relation to safe water In virtually all U S waters the nternational Association of Light house Authorities L ALA System B is followed Therefore the I ALA B system is discussed in this manual These designations are applied to navigable channels proceeding from sea ward toward the head limit of navigation The colors and numbers of buoys and lights along the coasts and along traffic routes not leading distinctly from seaward or toward headwaters follow the same system but applied so that even numbered aids mark the starboard side when proceeding in southerly direction along the Atlantic coast in a northerly and westerly direction along the gulf coast and in a north erly direction along the Pacific coast Table 5 2 provides a capsule summary of the charac teristics of lateral aid in most U S waters Ad ditional information on buoyage systems can be found in the Light List and other references e g Coast Guard Aids to Navigation Chapman Most ATONs used by mariners on a day to day basis for navigation purposes are main tained by the USCG In 1993 there were ap proximately 50 500 federal ATONs in U S wa ters Ihnat These aids include lights buoys lighted and unlighted daybeacons and ap proximately 200 marine radiobeacons As shown in figure 5 1 the majority 51 perce
55. nces of restricted visibility Charting Practices Fog signals are depicted by a symbol and appropriate abels and notes In most cases fog signals are located on fixed or floating aids to navigation Therefore the fog signal is charted using the appropriate symbol for the light or buoy Information on the fog signal is included in the labels associated with the ATON In some cases fog signals are included on structures not normally used for naviga tion In this case the andmark symbol see Chapter 6 is used and the appropriate label appended Labels and Notes Fog signals are labeled as DIAPHONE HORN SIREN WHISTLE BELL or GONG The appropriate designation see Section R of Chart No 1 is used as part of the characteristic of the aid Refer to the Light List for a detailed presentation of the sound se quence and period 5 28 NOAA Chart User s Manual p m FE mi i 7 i aS i E i a i me Ti i 3 PEN a el en J f U S Coast Guard ATON personnel servicing daymark and light Miami Honda Official U S Coast Guard Photograph Daybeacons Q navigator using a searchlight to more According to official charting definitions in readily locate them at night The color the Desk Reference Guide a daybeacon of the reflectors has the same signifi cance as the color of the aid Empha is an unlighted fixed aid spec
56. nt of these ATONs are buoys lights 25 percent and daybeacons 24 percent account for about equal portions of the remainder Fog signals are not included in this tabulation as these are typically collocated with a buoy or light In addition to federally maintained ATONSs there are approximately the same number of privately maintained ATONs Some privately maintained aids are useful for navigation and are tabulated in the Light List and shown on nautical charts Charting federal aids let alone some fraction of the private aids and keeping charts up to date is obviously a large under taking An ATON is charted if it is in the Light List or is assigned a Light List number when published in the LNM Thus any ATON found _ LIGHTS _ LIGHTED BUOYS UNUGHTED BUOYS DAYBEACONS SOURCE USCG Fig 5 1 Distibution of the more than 50 500 Federal ATONSs in U S waters in 1993 buoys are most numerous Aids to Navigation 9 5 Table 5 2 Characteristic Color Sha pe buoys Daymark Light color when fitted Reflectorcolor Numbers ifnumbered Port Hand Marks Green Cylindncal can orpillar Green square Green Green Odd Charactenstcs of IALA B Lateral System Starboard Hand Marks Red Conical nun orpillar Red triangle Red Red Even Ata pointwhere a channeldivides when proceeding inthe conventionaldirection of buoyage a preferred channelin Region Bmay be indicated bya modified portorst
57. of aid and a set of characteristics such as num ber height color and nominal range These characteristics are provided in abe s Symbols and characteristics are placed so as to be readily identified by the chart user not ob scured by less important information and to avoid overlap with any charted channels These standard symbols are reserved for ATONs which appear in the Light List Charted lights and beacons not intended as guides for normal surface navigation are shown with a andmark symbol see Nautical Chart Manual Chapter 6 Landmarks and identifying label Any identifying navigational light or beacon that is not established by the USCG or equivalent authority is identified on the charts either by the label Priv for pri vately maintained aids or by naming the agency that is responsible for its maintenance Temporary aids are seldom charted unless given a Light List number ATONs established and or aid characteristics that are changed for the winter navigation season are consid ered temporary aids and these changes are not charted However specific details for im portant aids such as seasonal fog signals at major aids are charted in all areas A seasonal aid note is found on all Great Lakes charts and on east coast charts from Cape Henry VA northward This note reads as follows SEASONAL AIDS During some winter months or when endangered by ice certain aids to navi gation are replaced by other types or
58. on and Bowditch the characteris tics of a light must always be checked on sight ing As noted by Moody An incorrectly iden tified mark is a hazard not an aid to naviga tion The eight of the light is the vertical dis tance between the light source not the top of the light and the shoreline reference datum Height is shown in feet using the abbreviation ft except on metric charts where height is shown in meters using the abbreviation m Height information is important for distance off calculations see Bowditch in daytime or for estimating the distance at which a light can be seen at night see below Normally the mariner should search for the highest lights first when approaching a coast as these are likely to be seen most easily However the mariner should bear in mind that lights placed at high elevations are more frequently obscured by clouds mist or fog than those lights located at or near sea level The visibility of the light is expressed as the nominal range and is charted except in the case of range lights or privately main tained lights t The nominal range is the maxi mum distance in nautical miles on most charts in statute miles on most Great Lakes charts a light may be seen at night in clear The nominal range is not given in the USCG Light List either because these are very short range ATONSsS Aids to Navigation Light Characters Light Characters on Light Buoys
59. on to be fol lowed The narrow sector may be flanked by an obscured or intensified light or by lights of a different color or characteristic A direc Fourteen Ft Bank Lightin Delaware Bay Note differencesin appearance with Miah Maull shown earlier Official U S Coast Guard Photograph 5 12 NOAA Chart User s Manual ee amp i S 54 j Big y Menemsha Bight Net g NOMANS LANDI k Age Dea 17 4 PA ge it eb ap Re ARE X 1 ace i ae x i Tanga ola ae waite i 9 l j 61 oer cy oBscuREP l 66 wo d e2 66 at prowelTe AREA X rf 1 ww 4 s te A Southwest Shoal oa D7 Fig 5 3 Excerptfrom NOS Chart No 13218 Martha s Vineyard to Block Island Note the obsc ured sectorofthe Gay Head Light south of Nomans Land The lightatGay Head isan altemating red and white with a period of 15 seconds and a nominal range of 20 nautical miles The height of this light is 170 ft Aids to Navigation 5 13 Fig 5 4 Excerpt from NOS Chart No 12304 Delaware Bay Note the red sector of the Brandywine Shoal Light The 60 ft light has a nominal range of 13 nautical miles Reference to the Light List indicates that this Is the lesser of the 17 mile range of the white light and the 13 mile range of the red sector The hom according to the Light List emits a 2 second blastevery 15 seconds The lightisa group occulting witha 12 second penod Note also the riprap symbol at the base of the light 5 14
60. ons of various types of buoys can be found in the Glossary in appendix A of this manual and the Light List Additionally the Light List pro vides an explanation of the significance of each buoy to the mariner The position of a buoy is shown with a small circle the approximate position sym bol see Chapter 6 because of the practical limitations in positioning and maintaining buoys and their sinkers in accurate geo graphic locations Buoys are charted insofar as possible in their published position on large scale charts In cases where a buoy po sition coincides with the symbol for another critical feature such as a rock awash the buoy may be charted slightly off position for clarity but always on the same azimuth as the feature that it marks If buoys are on op posite sides of a dredged channel and plot less than 0 5 mm apart the aids may be sepa rated to 0 5 mm Channel buoy symbols e g the diamond shape are generally shown at a 65 angle from the channel lines with the symbol pointing to ward the top of the chart Buoy symbols mark ing the limits of fish trap areas are oriented so as to fall inside the area For other buoys the orientation of the buoy symbols is approxi mately 25 from the vertical with the symbol inclined toward the label Lighted buoys except superbuoys are charted with a magenta disk 2 5 mm in diam eter centered on the circle located at the base of the buoy symbol The few buoys eq
61. ses where the channel is deep A vessel that ven tures too close to the buoy may no longer be in the channel Tii m_a 2 E nir A Standard Lighted Radar Reflective Buoy no sound Official U S Coast Guard Photograph 5 26 NOAA Chart User s Manual Junction Buoys Junction buoys typically mark a junction of two channels and can be passed safely on either side As with other buoys these can be lighted or unlighted If unlighted the buoy would re semble a green can if the preferred channel were to the right when ap proaching from seaward or a red nun if the preferred channel were to the left when approaching from seaward The nun would have hori zontal red and green bands with the topmost band red It would be charted by the symbol shown in Sec tion Q 4 of Chart No 1 The diamond shape would have two fills red and green topmost red and the let ters RG along with the letter s on the buoy shown in quotation marks If lighted these would be larger buoys but retain the same physical color and lettering scheme The color of the light matches the color of the topmost band These would be charted using the same symbols as given above except that the ma genta disc would be added along with the light characteristics as noted above Midchannel Buoys Midchannel buoys also called fairway buoys mark safe water at or near the center of the channel and can be passed on either side Physi
62. sun Official U S CoastGuard photograph As a point of interest the present LANBYs built originally to replace lightships are now nearing the end of their service life and are being replaced by smaller solar powered exposed location buoys ELBs The newer ELBs are cheaper to buy and main tain than the older diesel powered LNBs Walsh Charted Characteristics The characteristics of buoys include color and shape and if so equipped the color and period of their light Character istics are abbreviated as shown in Chart No 1 Sections Q 2 through Q 71 and a through U and the Light List These char acteristics are important to the mariner for identification purposes Indeed as with lights all mariners are cautioned to estab lish positive identification of each buoy in the vicinity of the vessel s track Notice ably absent from this list of characteris tics are the height of the buoy and the nominal range if lighted Nominal ranges for selected buoys can be found in the Light List and typically varies from about 4 to 6 nautical miles for most lighted buoys 0 24 NOAA Chart User s Manual Fig 5 6 Excerptfrom NOS ChartNo 12214 Cape May to Fenwick Island Note the LANBY in this illustration This buoy has a RACON with the identifier as well asa lightand a hom Buoy characteristics are shown in italic type These labels are placed so as not to overlap with wreck symbols shoals leas
63. t the vessel must alter course to the left right to rejoin the range Because of geometric consider ations the horizontal angle between the range markers seen by a vessel a fixed distance away from the channel centerline increases with decreasing distance Brogden Thus the sen sitivity of the angle to side to side excursions increases as the vessel draws closer to the markers The range markers provide an accu rate and easily obtained line of position Arti ficial ranges lighted or unlighted have been installed in line with channels in many ports In cases such as the Delaware River where the river has many bends separate ranges mark each of the straight sections and navi gation amounts to following a sequence of ranges throughout the voyage Most ranges are aligned with the center of the channel but in some areas more than one range is used to define the inbound and outbound ranges of the channel Range lights may be of any standard light color or period the principal requirement be ing that these stand out from their surround ings Thus for example green rather than red or white lights might be used to mark a range that would be aligned with the setting sun Most range lights show a high intensity beam within only a very narrow arc of visibility marking the channel centerline and are ob scured around the remainder of the horizon These lights appear to lose brilliance rapidly as the vessel strays from the range l
64. t depths and other critical features Buoys are identified on charts by their shape can nun spherical buoy spar buoy or pillar buoy and by any audible signal they emit bell whistle gong Buoys with the exception of mooring buoys are labeled as to their color using speci fied abbreviations given in Chart No 1 For example red buoys are shown with magenta fill labeled R and green buoys with green fill and labeled G The identifying number or letter s painted on the buoy not the LLNR is shown in quotation marks e g 22 Light characteristics and period are also presented in the label in much the same man ner as noted above for lights Private buoys listed in the Light List are identified with the label Priv in italic print The service name is charted on military ATONSs e g Navy Privately maintained buoys not listed in the Light List are not gen J erally charted A radar enhancing structure or reflective material has been installed on nearly all ma jor buoys and many minor buoys Therefore reference to this feature is not charted as part of the buoy s characteristics Instead the fol lowing note is included on the chart Radar reflectors have been placed on many floating aids to navigation Indi vidual radar reflector identification on these aids has been omitted from this chart On large scale charts the characteristics of buoys are shown in
65. the following standard ized order color omit if black shape if un lighted number or letter s flash character if lighted light color if lighted light period if lighted and fog signal if so equipped For example the complete legend would be charted as follows This is consistent with the convention that floating objects are shown in italics Black buoys are not discussed in this manual as these are being phased out Aids to Navigation 5 25 Lighted Buoy Unlighted Buoy R 22 R FI R 4s BELL N 22 In congested areas and on smaller scale charts some of these characteristics are some times omitted Characteristics of lighted buoys are omitted in the following order period color number light color and flash charac teristics For unlighted buoys the correspond ing order is color then number Space constraints do not permit an exhaus tive discussion of the many types of buoys found in U S waters However three of the most common types of buoys are briefly re viewed Channel Buoys These buoys mark the edges of navigable channels In the IALA B system red buoys mark the starboard side of the channel and green the port side of the channel when pro ceeding from seaward Unlighted red buoys have a conical shape called a nun and bear even numbers increasing from seaward These would be charted using the first symbol shown in Section Q 3 Q 20 of Chart No 1 and carry the label R
66. uipped with a RACON are charted with a 7 1 mm di ameter magenta circle centered on the circle located at the base of the buoy Superbuoys including single point moor ing buoys oceanographic data acquisition sys tems buoys ODAS and arge automated navi gation buoys LNB or LANBY share a unique symbol Sections P 8 and Q 26 of Chart No 1 See figure 5 6 for an illustration The word RACON is derived from RAdar beaCON A RACON produces a coded response Morse when triggered by a radar signal Aids to Navigation 5 21 Buoys and Beacons IALA Maritime Buoyage System which includes Beacons gt Q 130 1 Position of buoy gt Colors of Buoys and Beacon Topmarks Abbreviations for Colors gt P Green and black Single colors other than green and black Multiple colors in horizontal bands the color sequence is from top to bottom Multiple colors in vertical or diagonal stripes the darker color is given first Retroreflecting material Note Retroreflecting material may be fitted to some unlit marks Charts do not usually show it Under IALA Recommendations black bands will appear blue under a spotlight Lighted Marks Marks with Fog Signals R 7 Q A Lighted marks on standard charts Fr d Lighted marks on multicolored charts Topmarks and Radar Reflectors Topmarks on Special Purpose Buoys and Beacons gt Q For Application of Topmarks within t

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