CHAPTER 27NAVIGATIONREGULATIONSSHIP ROUTING2700.PurposeAndTypesOfRouting Systemsadjacent areas, or separates different classes ofships from one another.Navigation, once truly independent throughout theTraffic Lane: An area within which one-way traffic isworld, is an increasingly regulated activity.The conse-established.quencesof collision orgroundingfora large,modern shipcarrying tremendous quantities of high-value,perhaps dan-gerous cargo, are so severe that authorities have institutedRoundabout: A circular traffic lane used at junctionsmanytypesof regulations and control systemstominimizeofseveralroutes,withinwhichtrafficmovescoun-the chances of loss.Theserangefrom informal and volun-terclockwise around a separation point or zone.tary systems to closely controlled systems requiringInshoreTrafficZone:The areabetween atraffic sepcompliance with numerous regulations.The regulationsmayconcernnavigation,communications,equipment,proaration scheme and the adjacent coast, usuallycedures,personnel,and many other aspects of shipdesignated for coastal traffic.management.This chapter will be concerned primarilywithnavigation regulations and proceduresTwo-way Route:A two-way track for guidance ofThere are several specific types of regulation systemsships through hazardous areas.Forcommonlyusedopenoceanrouteswhereriskof colli-RecommendedRoute:Arouteestablishedforconve-sion is present, the use of recommended routes separatesships going in oppositedirections.In areas where ships con-nience of ship navigation, oftenmarked withverge at headlands, straits, and major harbors, trafficcenterline buoys.separation schemes (TSS)havebeen instituted to separateRecommended Track:A route,generallyfound tobevessels and control crossing and meeting situations.Envi-ronmentally sensitive areas may beprotected by areastofree of dangers, which ships are advised to followbe avoided which prevent vessels of a certain size or carry-toavoid possiblehazards nearby.ing certain cargoes from navigating within specifiedboundaries.In confinedwaterways such as canals,lock sys-Deep-Water Route:A route surveyed and chosen fothe passage of deep-draft vessels through shoaltems, and rivers leading tomajor ports,local navigationregulations control shipmovementareas.Precautionary Area: A defined area within which2701.Definitionsships must use particular caution and should fol-lowtherecommendeddirectionoftrafficflow.Thefollowing terms relateto ship's routingArea To Be Avoided: An area within which naviga-Routing System: Any system of routes or routingtion by certain classes of ships is preventedmeasures designed tominimizethe possibility ofbecauseof particularnavigational dangers or envi-collisions between ships, including TSS's, two-ronmentally sensitive natural features.way routes, recommended tracks, areas to beavoided, inshore traffic zones, precautionary ar-EstablishedDirection of TrafficFlow:The directioneas, anddeep-water routes.in which traffic within a lane must travel.Recommended Direction of Traffic Flow: The direc-Traffic Separation Scheme:Aroutingmeasurewhichseparatesopposingtrafficflowwithtrafficlanes.tion in which traffic is recommended to travel.Separation Zone or Line: A zone or line which sepa-There are various methods by which ships may be sep-rates opposing traffic,separates traffic fromarated using Traffic Separation Schemes. The simplest389
389 CHAPTER 27 NAVIGATION REGULATIONS SHIP ROUTING 2700. Purpose And Types Of Routing Systems Navigation, once truly independent throughout the world, is an increasingly regulated activity. The consequences of collision or grounding for a large, modern ship carrying tremendous quantities of high-value, perhaps dangerous cargo, are so severe that authorities have instituted many types of regulations and control systems to minimize the chances of loss. These range from informal and voluntary systems to closely controlled systems requiring compliance with numerous regulations. The regulations may concern navigation, communications, equipment, procedures, personnel, and many other aspects of ship management. This chapter will be concerned primarily with navigation regulations and procedures. There are several specific types of regulation systems. For commonly used open ocean routes where risk of collision is present, the use of recommended routes separates ships going in opposite directions. In areas where ships converge at headlands, straits, and major harbors, traffic separation schemes (TSS) have been instituted to separate vessels and control crossing and meeting situations. Environmentally sensitive areas may be protected by areas to be avoided which prevent vessels of a certain size or carrying certain cargoes from navigating within specified boundaries. In confined waterways such as canals, lock systems, and rivers leading to major ports, local navigation regulations control ship movement. 2701. Definitions The following terms relate to ship’s routing: Routing System: Any system of routes or routing measures designed to minimize the possibility of collisions between ships, including TSS’s, twoway routes, recommended tracks, areas to be avoided, inshore traffic zones, precautionary areas, and deep-water routes. Traffic Separation Scheme: A routing measure which separates opposing traffic flow with traffic lanes. Separation Zone or Line: A zone or line which separates opposing traffic, separates traffic from adjacent areas, or separates different classes of ships from one another. Traffic Lane: An area within which one-way traffic is established. Roundabout: A circular traffic lane used at junctions of several routes, within which traffic moves counterclockwise around a separation point or zone. Inshore Traffic Zone: The area between a traffic separation scheme and the adjacent coast, usually designated for coastal traffic. Two-way Route: A two-way track for guidance of ships through hazardous areas. Recommended Route: A route established for convenience of ship navigation, often marked with centerline buoys. Recommended Track: A route, generally found to be free of dangers, which ships are advised to follow to avoid possible hazards nearby. Deep-Water Route: A route surveyed and chosen for the passage of deep-draft vessels through shoal areas. Precautionary Area: A defined area within which ships must use particular caution and should follow the recommended direction of traffic flow. Area To Be Avoided: An area within which navigation by certain classes of ships is prevented because of particular navigational dangers or environmentally sensitive natural features. Established Direction of Traffic Flow: The direction in which traffic within a lane must travel. Recommended Direction of Traffic Flow: The direction in which traffic is recommended to travel. There are various methods by which ships may be separated using Traffic Separation Schemes. The simplest
390NAVIGATIONREGULATIONSscheme might consist of just one method;more complexone-wayortwo-way.Two-wayroutes showthebestwaterthrough confined areas such as inland routes among islandsschemeswilluseseveraldifferentmethodstogetherinaco-ordinated pattern torouteships to and from several areas atand reefs.Ships following these routes can expecttomeetonce.Schemes may be just a few miles in extent, or coverothervessels head-on and engage in normal passings.One-relatively large sea areas.wayroutes aregenerallyfound in areas wheremanyshipsare on similar or opposing courses.They and are intended2702.RecommendedRoutesAndTracksto separate opposing traffic so that most maneuvers areovertaking situations instead of the moredangerous meet-Recommended routes across the North Atlantic haveingsituation.beenfollowed since1898,whentheriskof collisionbe-2703.Charting Recommended Routestween increasing numbers of ships became too greatparticularly at junction points.The International Conven-tion for the Safety ofLife at Sea(SOLAS)codifies the useRecommendedroutes andrecommendedtracks areof certain routes.These routes vary with the seasons,withgenerally indicated on charts byblack lines,witharrow-winter and summer trackschosen so asto avoid iceberg-heads indicating the desired direction of traffic.Not allrecommended routes are charted.DMA charts generally de-proneareas.Theseroutes are often shown on charts,partic-ularly small scale ones,and aregenerally used to calculatepict recommended routes only on modified facsimiles madedistances between ports intables.directlyfromforeigncharts.Inall cases,recommendedRecommended routes consists of singletracks, eitherroutes arediscussed indetail in the Sailing DirectionsTRAFFICSEPARATIONSCHEMES2704.TrafficSeparation Schemes(TSS)Becauseofdifferences indatums,chartlets inthispubli-cation which depict the various schemes must not be usedIn 1961,representativesfrom England,France,andeitherfornavigationortocharttheschemes onnaviga-Germanymettodiscuss ways to separatetraffic inthecon-tional charts.The Notice to Mariners should be consultedfor charting details.gested Straits ofDoverand subsequently inother congestedareas.Their proposals were submitted to the International2705.MethodsOfTraffic SeparationMaritimeOrganization(IMO)andwereadoptedingeneralform.IMO expanded on theproposalsandhas sinceinsti-tuted a system of Traffic Separation Schemes (TSS)A number of different methods of separating trafficthroughoutthe worldhave been developed, using various zones, lines, and de-The IMO is the only international body responsibleforfined areas,One ormore methods may be employed inaestablishingandrecommendingmeasuresforship'sroutinggiventraffic schemeto direct and control converging orininternational waters.Itdoes notattempttoregulatetrafficpassing traffic.These arediscussedbelow.Refer to definiwithin the territorial waters of any nation.tions in section2701.In deciding whether or not to adopt a TSS, IMO con-Method 1.Separation ofopposing streams oftrafficbysiders the aids to navigation system in the area, the state ofhydrographic surveys in the area, the scheme's adherenceseparation zones or lines.Inthis method,typically a centralto accepted standards of routing,and theInternationalseparation zone is established within which ships are nottoRules of theRoad.The selection and development ofTSs'snavigate.The central zone isbordered by traffic lanes withare the responsibility of individual governments,who mayestablished directions oftraffic flow.The lanes areboundedseekIMOadoption of theirplans, especially if the systemon the outside by limiting lines.extends into international waters.GovernmentsmaydevelopandimplementTss'snotMethod2.Separationofopposing streamsoftrafficbyadopted bythe IMO,but in general only IMO-adoptednaturalfeaturesordefinedobjects.Inthismethodislandsschemes are charted.Rule10 of the International Regula-rocks,or otherfeaturesmaybe usedto separate traffic.Thetions forPreventing Collisions at Sea (Rules of theRoad)featureitselfbecomesthe separationzoneaddresses the subject of TSS's.This rule specifies the actions to betaken by various classes of vessels in and nearMethod3.Theseparationofthroughtrafficfromlocaltrafficschemes.trafficbyprovisionof inshoretrafficzones.Outsideoftraf-TrafficseparationschemesadoptedbytheIMO arefic schemes, ships maygenerally navigate in anydirectionlisted in Ship's Routing, a publication of the IMO, 4 Al-Inshore traffic zones provide an area within which localbertEmbankment,London SE17SR,UnitedKingdom.trafficmaytravel at will without interferencewith through
390 NAVIGATION REGULATIONS scheme might consist of just one method; more complex schemes will use several different methods together in a coordinated pattern to route ships to and from several areas at once. Schemes may be just a few miles in extent, or cover relatively large sea areas. 2702. Recommended Routes And Tracks Recommended routes across the North Atlantic have been followed since 1898, when the risk of collision between increasing numbers of ships became too great, particularly at junction points. The International Convention for the Safety of Life at Sea (SOLAS) codifies the use of certain routes. These routes vary with the seasons, with winter and summer tracks chosen so as to avoid icebergprone areas. These routes are often shown on charts, particularly small scale ones, and are generally used to calculate distances between ports in tables. Recommended routes consists of single tracks, either one-way or two-way. Two-way routes show the best water through confined areas such as inland routes among islands and reefs. Ships following these routes can expect to meet other vessels head-on and engage in normal passings. Oneway routes are generally found in areas where many ships are on similar or opposing courses. They and are intended to separate opposing traffic so that most maneuvers are overtaking situations instead of the more dangerous meeting situation. 2703. Charting Recommended Routes Recommended routes and recommended tracks are generally indicated on charts by black lines, with arrowheads indicating the desired direction of traffic. Not all recommended routes are charted. DMA charts generally depict recommended routes only on modified facsimiles made directly from foreign charts. In all cases, recommended routes are discussed in detail in the Sailing Directions. TRAFFIC SEPARATION SCHEMES 2704. Traffic Separation Schemes (TSS) In 1961, representatives from England, France, and Germany met to discuss ways to separate traffic in the congested Straits of Dover and subsequently in other congested areas. Their proposals were submitted to the International Maritime Organization (IMO) and were adopted in general form. IMO expanded on the proposals and has since instituted a system of Traffic Separation Schemes (TSS) throughout the world. The IMO is the only international body responsible for establishing and recommending measures for ship’s routing in international waters. It does not attempt to regulate traffic within the territorial waters of any nation. In deciding whether or not to adopt a TSS, IMO considers the aids to navigation system in the area, the state of hydrographic surveys in the area, the scheme’s adherence to accepted standards of routing, and the International Rules of the Road. The selection and development of TSS’s are the responsibility of individual governments, who may seek IMO adoption of their plans, especially if the system extends into international waters. Governments may develop and implement TSS’s not adopted by the IMO, but in general only IMO-adopted schemes are charted. Rule 10 of the International Regulations for Preventing Collisions at Sea (Rules of the Road) addresses the subject of TSS’s. This rule specifies the actions to be taken by various classes of vessels in and near traffic schemes. Traffic separation schemes adopted by the IMO are listed in Ship’s Routing, a publication of the IMO, 4 Albert Embankment, London SE1 7SR, United Kingdom. Because of differences in datums, chartlets in this publication which depict the various schemes must not be used either for navigation or to chart the schemes on navigational charts. The Notice to Mariners should be consulted for charting details. 2705. Methods Of Traffic Separation A number of different methods of separating traffic have been developed, using various zones, lines, and defined areas. One or more methods may be employed in a given traffic scheme to direct and control converging or passing traffic. These are discussed below. Refer to definitions in section 2701. Method 1. Separation of opposing streams of traffic by separation zones or lines. In this method, typically a central separation zone is established within which ships are not to navigate. The central zone is bordered by traffic lanes with established directions of traffic flow. The lanes are bounded on the outside by limiting lines. Method 2. Separation of opposing streams of traffic by natural features or defined objects. In this method islands, rocks, or other features may be used to separate traffic. The feature itself becomes the separation zone. Method 3. The separation of through traffic from local traffic by provision of inshore traffic zones. Outside of traffic schemes, ships may generally navigate in any direction. Inshore traffic zones provide an area within which local traffic may travel at will without interference with through
391NAVIGATIONREGULATIONStraffic in the lanes.Inshore zones are separatedfrom trafficflow well-defined.lanes by separation zones or lines.2706.RepresentingTSS's OnChartsMethod4.Division oftraffic from several different di-See Figure 2706. Depiction of TSS's on charts uses ma-rection into sectors: This approach is used at points ofgenta (purple) as the primary color. Zones are shown byconvergencesuchaspilotstations andmajorentrancespurple tint, limits are shown by T-dashes such as are used inMethod 5.Routing traffic through junctions of two orother maritime limits, and lines are dashed. Arrows are open-moremajorshippingroutes.Theexactdesignoftheschemelined ordashed-lined depending on use.Special provisionsin this method varies with conditions.It may be a circularapplying toa schememaybementioned innotes on thechartDeep water routes will be marked with the designation“DWor rectangular precautionary area, a roundabout, or a junc-tionoftworouteswithcrossingroutesanddirectionsofin bold purple letters, and the least depth may be indicated.SymbolDescriptionApplicationsRoutingtermTraffic separationOutlined arrowEstablished1schemes and deep-direction ofwaterroutes (whentraffie flowpart ofa traffic lane)Precautionary areas,Recommended2Dashed outlinedtwo-way routes,direction ofarrowCVrecommended routestraffic flowand deep-waterroutes3Separation linesTint, 3mm wideTraffic separationschemes and betweentraffic separationschemes and inshoretrafficzoneTint, may be4 Separation zonesTraffic separationany shapeschemes and betweentraffic separationschemes and inshoretraffic zones5 Limits ofT-Shaped dashesAreas to be avoidedrestricted areasand defined ends of(charting term)inshore traffic zonesDashed line6 General maritimeTraffic separationeebeeelimits (chartingschemes,precautionaryterm)areas,two-way routesanddeep-waterroutes7ReeommendedGenerally reservedDashed linestracks:one-wayfor use by chartingwith arrowheadsa.*two-wayauthorities(colour black)8RecommendedDashed line andRecommended routesroutesdashed outlinedarrowsPrecautionaryPrecautionaryPrecautionary areasareassymbolFigure2706.Traffic separation scheme symbology.On charts the symbols are usually inmagenta
NAVIGATION REGULATIONS 391 traffic in the lanes. Inshore zones are separated from traffic lanes by separation zones or lines. Method 4. Division of traffic from several different direction into sectors. This approach is used at points of convergence such as pilot stations and major entrances. Method 5. Routing traffic through junctions of two or more major shipping routes. The exact design of the scheme in this method varies with conditions. It may be a circular or rectangular precautionary area, a roundabout, or a junction of two routes with crossing routes and directions of flow well-defined. 2706. Representing TSS’s On Charts See Figure 2706. Depiction of TSS’s on charts uses magenta (purple) as the primary color. Zones are shown by purple tint, limits are shown by T-dashes such as are used in other maritime limits, and lines are dashed. Arrows are openlined or dashed-lined depending on use. Special provisions applying to a scheme may be mentioned in notes on the chart. Deep water routes will be marked with the designation “DW” in bold purple letters, and the least depth may be indicated. Figure 2706. Traffic separation scheme symbology. On charts the symbols are usually in magenta
392NAVIGATIONREGULATIONS2707.Use OfTraffic Separation Schemesnal “YG"is provided in the International Code of Signals toindicate to another ship:“You appear notto be complyingA TSS is not officially approved for use until adopted bywiththetrafficseparationscheme.the IMO.Once adopted, it is implemented as ofa certain timeTSS's are discussed in detail in the Sailing Directionsand date,as announced intheNoticeto Marinersandperhapsfor the areas where they arefound.throughothermeans.TheNoticetoMarinerswillalsode-2708.Areas ToBe Avoidedscribe the scheme's general location and purpose and givespecificdirections inthechartcorrection sectiononplottingAreas to be avoided are adopted by the IMO and arethevariouszonesandlineswhichdefineit.Thesecorrectionsusually applyto several charts.Becausethecharts mayrangeusuallyestablishedtopreventpossiblegroundingoftankersin scalefrom quite small to verylarge,thecorrections forand other shipscarryinghazardouscargoin environmental-eachshouldbefollowedcloselyThepositionsforthevari-ly sensitive areas.Theymay also be established to keepousfeaturesmaybeslightlydifferentfromcharttochartdueparticular classes of ships away from areas where naviga-todifferences inrounding off positions orchartdatum.tionisparticularlyhazardousATSS may be amended for periods of time rangingThey are depicted on charts by dashed lines or T-dashedfrom afewhours to several years.Underwater constructionlines,eitherpoint to point straight lines oras a circle cen-works, surveying, dredging, and other transitory activitiestered on a feature in question such as a rock or island. Thewill benoted by radiobroadcast,Local NoticeToMariners.smallestmay coverless thanamile inextent,thelargestmayor other means.Longer duration activities such as place-coverhundreds of squaremiles of coral reefs ordangerousmentofoildrillingrigs,platforms,orpipelinesmayrequireshoals.Notes on the appropriate charts and in Sailing Direc-a charted changeto the scheme,which may become aper-tionstell which classes of ships are excluded from the areamanentfeature.ThesewillbeNoticetoMarinersitems2709.Special RulesUseofTSS'sbyall ships isrecommended.Theyare in-tended for use in all weather,day and night.Adequate aidsto navigation are a part of all TSs's. There is no specialCertain special rules adopted by IMO apply in constrict-rightofoneshipoveranotherinTSS'sbecausetheRulesofed areas such as the Straits of Malacca and Singapore, thethe Road apply in all cases. Deep-water routes should beEnglishChannel andDover Strait,and intheGulf of Suezavoidedby ships whichdonotneed themtokeepthemclearTheseregulations are summarized intheappropriate Sailingfor deep-draft vessels. Ships need not keep strictly to theDirections (PlanningGuides).Fora complete summary ofcourses indicatedbythearrows,but arefreetonavigate asworldwide ships'routing measures, the IMO publicationnecessary within their lanes to avoid other traffic.The sig-Ship'sRouting shouldbe obtained.See paragraph2704VESSELTRAFFICSERVICES(VTS)2710.DevelopmentAndPurposeimproveall-weatheroperatingcapabilityAVHF-FMcommunicationsnetworkformsthebasisThepurposeofVessel TrafficServices(VTS)istopro-ofmostmajorservices.Transitingvesselsmakeposition re-vide active monitoringand navigational advice for vessels inports to anoperations centerbyradiotelephoneand are inparticularly confined and busy waterways.There aretwoturn providedwith accurate,complete,and timelynaviga-main types of VTS, surveilled and non-surveilled. Sur-tional safetyinformation.The additionof anetwork ofveilled systems consist ofone ormore land-based radar sitesradarsforsurveillanceandcomputer-assistedtrackingandwhich output their signals to a central location where opera-tagging,similarto that used in airtrafficcontrol,allows thetors monitor and to a certain extent control trafficflows.VTs to play a more significant role in marine traffic man-Non-surveilled svstems consistof one or more calling-inagement,thereby decreasing vessel congestion, criticalpoints at which ships are required to report their identity,encounter situations, and the probability of a marine casu-alty resulting in environmental damage.Surveilled VTS'scourse,speed,and other datatothemonitoringauthority.VesselTrafficServicesintheU.S.areimplementedarefoundinmanylargeportsandharborswherecongestionunder the authority of thePorts and Waterways Safety Actis a safety and operational hazard.Less sophisticated ser-of1972(PublicLaw92-340asamended)and the St.viceshave been established in other areas in responsetohazardous navigational conditions according to the needsLawrenceSeawayAct(PublicLaw358).They encompassa wide range of techniques and capabilities aimed at pre-and resources of the authorities.venting vessel collisions,rammings,and groundings in the2711.Brief HistoryOfVTSharbor/harborapproachandinlandwaterwayphaseofnav-igation.Theyare also designed toexpedite shipSince the early 1960's the U.S.Coast Guard has beenmovements,increasetransportationsystemcapacity,and
392 NAVIGATION REGULATIONS 2707. Use Of Traffic Separation Schemes A TSS is not officially approved for use until adopted by the IMO. Once adopted, it is implemented as of a certain time and date, as announced in the Notice to Mariners and perhaps through other means. The Notice to Mariners will also describe the scheme’s general location and purpose and give specific directions in the chart correction section on plotting the various zones and lines which define it. These corrections usually apply to several charts. Because the charts may range in scale from quite small to very large, the corrections for each should be followed closely. The positions for the various features may be slightly different from chart to chart due to differences in rounding off positions or chart datum. A TSS may be amended for periods of time ranging from a few hours to several years. Underwater construction works, surveying, dredging, and other transitory activities will be noted by radio broadcast, Local Notice To Mariners, or other means. Longer duration activities such as placement of oil drilling rigs, platforms, or pipelines may require a charted change to the scheme, which may become a permanent feature. These will be Notice to Mariners items. Use of TSS’s by all ships is recommended. They are intended for use in all weather, day and night. Adequate aids to navigation are a part of all TSS’s. There is no special right of one ship over another in TSS’s because the Rules of the Road apply in all cases. Deep-water routes should be avoided by ships which do not need them to keep them clear for deep-draft vessels. Ships need not keep strictly to the courses indicated by the arrows, but are free to navigate as necessary within their lanes to avoid other traffic. The signal “YG” is provided in the International Code of Signals to indicate to another ship: “You appear not to be complying with the traffic separation scheme.” TSS’s are discussed in detail in the Sailing Directions for the areas where they are found. 2708. Areas To Be Avoided Areas to be avoided are adopted by the IMO and are usually established to prevent possible grounding of tankers and other ships carrying hazardous cargo in environmentally sensitive areas. They may also be established to keep particular classes of ships away from areas where navigation is particularly hazardous. They are depicted on charts by dashed lines or T-dashed lines, either point to point straight lines or as a circle centered on a feature in question such as a rock or island. The smallest may cover less than a mile in extent; the largest may cover hundreds of square miles of coral reefs or dangerous shoals. Notes on the appropriate charts and in Sailing Directions tell which classes of ships are excluded from the area. 2709. Special Rules Certain special rules adopted by IMO apply in constricted areas such as the Straits of Malacca and Singapore, the English Channel and Dover Strait, and in the Gulf of Suez. These regulations are summarized in the appropriate Sailing Directions (Planning Guides). For a complete summary of worldwide ships’ routing measures, the IMO publication Ship’s Routing should be obtained. See paragraph 2704. VESSEL TRAFFIC SERVICES (VTS) 2710. Development And Purpose The purpose of Vessel Traffic Services (VTS) is to provide active monitoring and navigational advice for vessels in particularly confined and busy waterways. There are two main types of VTS, surveilled and non-surveilled. Surveilled systems consist of one or more land-based radar sites which output their signals to a central location where operators monitor and to a certain extent control traffic flows. Non-surveilled systems consist of one or more calling-in points at which ships are required to report their identity, course, speed, and other data to the monitoring authority. Vessel Traffic Services in the U.S. are implemented under the authority of the Ports and Waterways Safety Act of 1972 (Public Law 92-340 as amended) and the St. Lawrence Seaway Act (Public Law 358). They encompass a wide range of techniques and capabilities aimed at preventing vessel collisions, rammings, and groundings in the harbor/harbor approach and inland waterway phase of navigation. They are also designed to expedite ship movements, increase transportation system capacity, and improve all-weather operating capability. A VHF-FM communications network forms the basis of most major services. Transiting vessels make position reports to an operations center by radiotelephone and are in turn provided with accurate, complete, and timely navigational safety information. The addition of a network of radars for surveillance and computer-assisted tracking and tagging, similar to that used in air traffic control, allows the VTS to play a more significant role in marine traffic management, thereby decreasing vessel congestion, critical encounter situations, and the probability of a marine casualty resulting in environmental damage. Surveilled VTS’s are found in many large ports and harbors where congestion is a safety and operational hazard. Less sophisticated services have been established in other areas in response to hazardous navigational conditions according to the needs and resources of the authorities. 2711. Brief History Of VTS Since the early 1960’s the U.S. Coast Guard has been
393NAVIGATIONREGULATIONSinvestigating various concepts by which navigational safetyoptimumparametersforfutureprocurements.can be improved intheharborandharbor approachareas.Afteraperiodofextensiveengineering evaluation,theEquipment installations in various portsforthis investiga-radar system was accepted in May 1973 as an operationaltion have included shore-based radar, low light level,replacementfortheequipment installedearlierattheHARclosed-circuit television (LLL-CCTV); VHF-FM commu-In 1980 an analysis indicated that a modified version ofnications, broadcast television, and computer driventhe Coast Guard standard shipboard radar would meet allelectronic situation displays.the VTS standard operating requirements. Additionally, itIn1962an experimental installationcalledRatan (Rawas more cost effective to procure and maintain than thespecially designed, non-standard radar. After a period ofdarand Television AidtoNavigation)was completed inevaluation at VTS SanFrancisco and with certaintechnicalNewYork Harbor.In this systema radarat SandyHookNewJersey,scanned theapproachestotheharbor.Thera-modifications,thestandard radar was acceptedfor VTSuse.The radar includes a tracking system which enhancesdarvideo,formattedbya scanconversion storagetube,wasbroadcast by a television band UHF transmitterThis en-the radar capability by allowing theVTS totrack upto20targets automatically.ThePPI can operate in an environ-abledmarinerstoobserveoncommercial televisionsetsthement that is half as bright asa normal roomwith an optionpresentationontheradarscopeatSandyHook.Themarinerfor a TVtype display that can operate under any lightingcould identify his vessel on the television screen by execut-conditions.Thesenewradars are also required to provideing a turn and by observing the motions ofthe targets.Thedata to a computer system,have 60 navigational line capa-highpersistencycreated bythe scan converterprovided tar-bility,and display ranges in yards or nautical miles.get"tails"whichaidedinobservingtargetmovement.ThisRatanexperimentwas discontinuedprimarilybecauseofThe newradarwas installed inVTS Prince Williamallocation ofthecommercial televisionfrequency spectrumSound in August 1984.VTS Houston-Galveston's radarwasreplaced in January1985.VTS SanFranciscoradarsforotherpurposes.werereplaced inMay1985.VTSNewYorkreopened inIn January1970theCoast Guard established a harborlate1990 and will continue to add coverage areas until theradarfacilityin SanFranciscotogatherdataonvesseltrafficproject is completed in 1995.patterns.The informationwasused todetermineparametersfor new equipment procurements.The initial installation2712.OperationalSystemsconsistedof standardmarineX-band(3-centimeter)searchradars located onPoint Bonita and Yerba Buena Island inVTSNew York became operational inDecemberSanFranciscoBay.Radar video wasrelayed fromthesetwo1990. It had been open previously but was closed in 1988radar sites toa manned center colocated with the SanFran-cisco Marine Exchange.When the parameter definitiondueto a change infundingpriorities.workwascompleted,VHF-FMcommunicationsequipmentThis VTS has the responsibility of coordinating vesselwasaddedtoenablecommunications throughouttheharbortrafficmovements inthebusyports of NewYorkand Newarea. This experimental system, previously called HarborJersey.The VTS New York area includes the entrance toAdvisoryRadar(HAR)was designated inAugust1972asthe harbor via Ambroseand Sandy Hook Channels,throughanoperationalVessel TrafficSystem(VTS);acontinuoustheVerrazano Narrows Bridgeto theBrooklyn Bridge inradarwatchwithadvisoryradiobroadcaststotrafficinthethe East River,to the Holland Tunnel in the Hudson River,harbor wasprovided.This change fromHAR to VTS coin-and the Kill Van Kull including Newark Bay. Future planscided with the effective date of the Ports and Waterwayscall for the VTS area to be expanded to include the EastSafetyAct of 1972,authorizing the U.S.Coast Guard to in-River to Throgs Neck, all of Arthur Kill, and Raritan Bay.stall and operate such systems in United States waters toVTS New York is presently undergoing an upgradeincreasevessel safetyandtherebyprotecttheenvironment.which includes the installation of state-of-the-art equip-ment in a newoperations center.The current operation usesIn late 1972 improved developmental radar systemssurveillancedataprovidedby4radarsitesand3closedcirwere installed side by side with the operational system, oper-cuitTVsites.VTScommunications areonVHF/FMatedbvanewresearch evaluationcenterat YerbaBuenachannels 12 and 14.Island.Redundantoperator-switchabletransceiversprovided50kWpeakpowerand incorporated receivers with largedy-VTS SanFrancisco was commissioned in August ofnamic ranges of automatic gain control giving considerable1972.When theoriginal radar systembecameoperationalprotection against receiver saturation by interfering signalsinMay1973,thecontrolcenterforVTSSanFranciscowasand interferencebyrainand seaclutter.Parabolicantennasshiftedto the Yerba Buena Island.This center was designat-withaperturesof27feet(8.2meters)and beamwidthsof0.3edaVesselTrafficCenter (VTC).degrees improvedtheradarsystem accuracy.Variablepulselengths(50and200nanoseconds),threepulserepetitionAs ofearly1985,themajor componentsofthe systemrates(1000,2500,and4000pps),tworeceiverbandwidthsinclude a Vessel Traffic Center at Yerba Buena Island, two(22MHz and 2MHz),and threeantennapolarizations (hori-high resolution radars,a VHF-FM communicationsnet-zontal,vertical, and circular)were provided to evaluate thework,atraffic separation scheme,andavesselmovement
NAVIGATION REGULATIONS 393 investigating various concepts by which navigational safety can be improved in the harbor and harbor approach areas. Equipment installations in various ports for this investigation have included shore-based radar; low light level, closed-circuit television (LLL-CCTV); VHF-FM communications; broadcast television; and computer driven electronic situation displays. In 1962 an experimental installation called Ratan (Radar and Television Aid to Navigation) was completed in New York Harbor. In this system a radar at Sandy Hook, New Jersey, scanned the approaches to the harbor. The radar video, formatted by a scan conversion storage tube, was broadcast by a television band UHF transmitter. This enabled mariners to observe on commercial television sets the presentation on the radarscope at Sandy Hook. The mariner could identify his vessel on the television screen by executing a turn and by observing the motions of the targets. The high persistency created by the scan converter provided target “tails” which aided in observing target movement. This Ratan experiment was discontinued primarily because of allocation of the commercial television frequency spectrum for other purposes. In January 1970 the Coast Guard established a harbor radar facility in San Francisco to gather data on vessel traffic patterns. The information was used to determine parameters for new equipment procurements. The initial installation consisted of standard marine X-band (3-centimeter) search radars located on Point Bonita and Yerba Buena Island in San Francisco Bay. Radar video was relayed from these two radar sites to a manned center colocated with the San Francisco Marine Exchange. When the parameter definition work was completed, VHF-FM communications equipment was added to enable communications throughout the harbor area. This experimental system, previously called Harbor Advisory Radar (HAR) was designated in August 1972 as an operational Vessel Traffic System (VTS); a continuous radar watch with advisory radio broadcasts to traffic in the harbor was provided. This change from HAR to VTS coincided with the effective date of the Ports and Waterways Safety Act of 1972, authorizing the U.S. Coast Guard to install and operate such systems in United States waters to increase vessel safety and there by protect the environment. In late 1972 improved developmental radar systems were installed side by side with the operational system, operated by a new research evaluation center at Yerba Buena Island. Redundant operator-switchable transceivers provided 50 kW peak power and incorporated receivers with large dynamic ranges of automatic gain control giving considerable protection against receiver saturation by interfering signals and interference by rain and sea clutter. Parabolic antennas with apertures of 27 feet (8.2 meters) and beam widths of 0.3 degrees improved the radar system accuracy. Variable pulse lengths (50 and 200 nanoseconds), three pulse repetition rates (1000, 2500, and 4000 pps), two receiver bandwidths (22 MHz and 2 MHz), and three antenna polarizations (horizontal, vertical, and circular) were provided to evaluate the optimum parameters for future procurements. After a period of extensive engineering evaluation, the radar system was accepted in May 1973 as an operational replacement for the equipment installed earlier at the HAR. In 1980 an analysis indicated that a modified version of the Coast Guard standard shipboard radar would meet all the VTS standard operating requirements. Additionally, it was more cost effective to procure and maintain than the specially designed, non-standard radar. After a period of evaluation at VTS San Francisco and with certain technical modifications, the standard radar was accepted for VTS use. The radar includes a tracking system which enhances the radar capability by allowing the VTS to track up to 20 targets automatically. The PPI can operate in an environment that is half as bright as a normal room with an option for a TV type display that can operate under any lighting conditions. These new radars are also required to provide data to a computer system, have 60 navigational line capability, and display ranges in yards or nautical miles. The new radar was installed in VTS Prince William Sound in August 1984. VTS Houston-Galveston’s radar was replaced in January 1985. VTS San Francisco radars were replaced in May 1985. VTS New York reopened in late 1990 and will continue to add coverage areas until the project is completed in 1995. 2712. Operational Systems VTS New York became operational in December 1990. It had been open previously but was closed in 1988 due to a change in funding priorities. This VTS has the responsibility of coordinating vessel traffic movements in the busy ports of New York and New Jersey. The VTS New York area includes the entrance to the harbor via Ambrose and Sandy Hook Channels, through the Verrazano Narrows Bridge to the Brooklyn Bridge in the East River, to the Holland Tunnel in the Hudson River, and the Kill Van Kull including Newark Bay. Future plans call for the VTS area to be expanded to include the East River to Throgs Neck, all of Arthur Kill, and Raritan Bay. VTS New York is presently undergoing an upgrade which includes the installation of state-of-the-art equipment in a new operations center. The current operation uses surveillance data provided by 4 radar sites and 3 closed circuit TV sites. VTS communications are on VHF/FM channels 12 and 14. VTS San Francisco was commissioned in August of 1972. When the original radar system became operational in May 1973, the control center for VTS San Francisco was shifted to the Yerba Buena Island. This center was designated a Vessel Traffic Center (VTC). As of early 1985, the major components of the system include a Vessel Traffic Center at Yerba Buena Island, two high resolution radars, a VHF-FM communications network, a traffic separation scheme, and a vessel movement