Raymarine c97 - Page 178

Thereareconditionswhereacquiringatargetmaybecome
difcult.Thesesameconditionsmaybeafactorinsuccessfully
trackingatarget.Someoftheconditionsare:
•Thetargetechoisweak.Thetargetisveryclosetoland,
buoysorotherlargetargets.
•Thetargetoryourownvesselismakingrapidmanoeuvres.
•Choppyseastateconditionsexistandthetargetisburiedin
excessiveseaclutterorindeepswells.
•Choppyseastateconditionsexistyieldingpoorstability;own
vessel’sheadingdataisveryunstable.
•Inadequateheadingdata.
Symptomsofsuchconditionsinclude:
•targetacquisitionisdifcultandtheMARPAvectorsare
unstable;
•thesymbolwandersawayfromthetarget,locks-ontoanother
target,orchangestoalostsymboltarget.
Inthesecircumstances,targetacquisitionandtrackingmay
needtobere-initiatedandinsomecasesmightbeimpossible
tomaintain.Betterqualityheadingdatamightimprove
performanceinthesecircumstances.
HowaMARPAriskisassessed
Eachtargetismonitoredtoascertainwhetheritwillbewithina
certaindistancefromyourvesselwithinacertaintime.Ifso,the
targetisdesignatedasdangerous,andanaudiblewarningis
soundedandawarningdisplayed.Thetargetsymbolchanges
tothedangeroustargetsymbolandashestoindicatethatitis
adangeroustarget.Acknowledgingthealarmwillremovethe
warning.
Ifatargetislost,eitherbecausetheMARPAsoftwarehas
lostcontactwithit,orbecauseithasmovedoutofrange,an
audiblealarmissoundedandanon-screenwarningappears.
Theon-screensymbolwillchangetothetargetlostsymbol.
Acknowledgingthewarningwillsilencethealarmandremove
theon-screenwarningandthetargetlostsymbol.
EffectiverangeforMARPAtargets
MARPAtargetacquisitionisonlyavailableatradarrangescales
ofupto12nm,althoughtrackingcontinuesatallranges.
Ifyouchangetoasmallerrangescale,targetsmaybebeyond
therangeofyourradarscannerandwillbelost.Insuchcases,
anon-screenwarningindicatesthatthetargetisoff-screen.
MARPAcontextmenu
TheMARPAfunctionincludesacontextmenuwhichprovides
positionaldataandmenuitems.
Thecontextmenuprovidesthefollowingtargetinformation:
•CPA
•TCPA
•COG
•SOG
Thecontextmenualsoprovidethefollowingmenuitems:
•Canceltarget
•CPAGraphic
•MARPAData
•Slewthermalcamera(Onlyavailablewhenthermalcamera
isconnectedandoperating.)
Accessingthecontextmenu
Youcanaccessthecontextmenubyfollowingthestepsbelow.
1.NeweSeriesorNewcSeries:
i.Selectingalocation,objectortargeton-screenand
pressingtheOkbutton.
2.T ouchscreenmultifunctiondisplays:
i.Selectinganobjectortargeton-screen.
ii.Selectingandholdingonalocationon-screen.
ConguringMARPAoptions
Fromtheradarapplication:
1.SelectMenu.
2.SelectTrackTargets.
3.SelectMARPAOptions.
Note:IfAISdataisavailablethemenuwillbeMARPA&AIS
Options.
4.SelectVectorLength.
5.Selectanappropriatetimeperiod.
Thedistancethatyourvesseltravelsinthetimeperiodyou
specifyheredeterminesthelengthofthevectorlines.
6.SelectMARPATargetHistory.
7.Selectanappropriatetimeperiod.
Thetarget'spreviouspositionwillbeplottedontheradar
displayasatargeticonwithlightershadingthantheactual
target.
Note:MARPAandAISfunctionsshareSafeZoneand
VectorLengthsettings.
ConguringsafezonesetupforMARPA
FromtheRadarapplication:
1.SelectMenu.
2.SelectTrackTargets.
3.SelectSafeZoneSet-up.
4.SelectSafeZoneRadius.
i.SelectadistancefortheSafeZone.
Thisisthedistancefromyourvesselthatthesafezone
willbesetup.
5.SelectTimetoSafeZone.
i.Selectatimeperiod.
Atargetisconsidereddangerousifitwillenteryoursafe
zonewithinthistimeperiod.
6.SelectSafeZoneRing.
Selectingsafezoneringwillswitchbetweenshowingand
hidingthesafezoneringintheradarapplication.
UsingMARPA
AcquiringaMARPAtargettotrack
Fromtheradarapplication:
1.Selectthetargettobeacquired.
TheMARPAcontextmenuisdisplayed.
2.SelectAcquireTarget.
The“targetbeingacquired”symbolisdisplayed.Ifthetargetis
presentforseveralscans,theradarlocks-ontothetarget,and
thesymbolchangesto“safetarget”status.
CancellingaMARPAtargetusingtheMARPAcontextmenu
Fromtheradarapplication:
1.Selecttherelevanttarget.
TheMARPAcontextmenuisdisplayed.
2.SelectCancelTargetorCancelAllTargets.
CancellingaMARPAtargetusingthemenu
1.SelectMenu.
2.SelectTrackTargets.
3.SelectViewMARPALists.
Note:IfAISdataisavailablethemenuwillbeViewMARPA
&AISLists.
178NewaSeries/NewcSeries/NeweSeries