Raymarine AIS 350 - AIS Overview and Classes

2.5AISoverview
YourAISdeviceusesdigitalradiosignalstoexchange'real-time'
informationbetweenvessels,shorebasedstations,oraidsto
navigation(AT oNs)ondedicatedVHFfrequencies.Thisinformation
isusedtoidentifyandtrackvesselsinthesurroundingareaandto
providefast,automaticandaccuratecollisionavoidancedata.
AlthoughAISaugmentsyourradarapplicationbyoperatinginradar
blindspotsanddetectingsmallerAIS-ttedvessels,itdoesnot
replaceradar,asitreliesonreceivingtransmittedAISinformation
andthereforecannotdetectobjectssuchaslandmassesand
navigationalbeacons.
NEVERassumethatAISisdisplayinginformationfromallvessels
inthearea,because:
•NotallvesselsarettedwithAIS
•Althoughitismandatoryforlargercommercialvesselstocarry
AIS,itisnotmandatorytouseit.
AISshouldbeusedonlytoaugmentradarinformation,notsubstitute
it.
Warning:AISlimitation
NeverassumethatyourAISisdetectingallvessels
inthearea.Alwaysexercisedueprudenceanddo
notuseAISasasubstituteforsoundnavigational
judgement.
2.6ClassesofAIS
TheAIS350isareceiverthatreceivesmessagesfromvessels,
landbasestations,oraidstonavigation(AT oNs)carryingClassA
orClassBtransceivers.
TheAIS650isaClassBtransceiverthatreceivesmessagesfrom
andtransmitsmessagestovessels,landbasestations,oraidsto
navigation(AT oNs)carryingClassAorClassBtransceivers.
ClassAtransceivers
ClassAAIStransceiverstransmitandreceiveAISsignals.AIS
transceiversarecurrentlymandatoryonallcommercialvessels
exceeding300tonsthattravelinternationally(SOLASvessels).
ThefollowinginformationcanbetransmittedbyaClassAAIS
system:
•Staticdata.Includesinformationsuchasvesselname,vessel
type,MMSInumber,callsign,IMOnumber,length,beamand
GPSantennalocation.
•Voyagerelateddata.Includesinformationsuchasdraft,cargo,
destination,ETAandotherrelevantinformation.
•Dynamicdata.Includesinformationsuchastime(UTC),ship’s
position,COG,SOG,heading,rateofturnandnavigationalstatus.
•Dynamicreports.Ship’sspeedandstatus.
•Messages.Alarmsandsafetymessages.
Rememberthatnotallvesselswilltransmitalloftheinformation.
ClassBtransceivers
ClassBAIStransceiverstransmitandreceiveAISsignals,butuse
areducedsetofdatacomparedtoClassA(seeDataSummary).A
ClassBAIStransceivercanbettedonanyvesselnotttedwitha
ClassAtransceiver,butisnotmandatoryaboardanyvessel.
16AIS350/AIS650