Advancedl{avigationGuide
Thc Star Pilot is designedto be theeasiestto useGPSsystem availabletoday.The prevroussectionsof theoperationmanualhave detailedthebasicsof installationandoperationof theStar Pilot.To utilizethesystemto its optimum.thefollowingsectionon naviqation shouldbe studiedBy. becomingmorefamiliarwith thesenaviga- tionalandGPStermsandconceptsyou. will increaseyour own navigationalskills.
GPS Modes
The Star Pilot operatesin an automaticGPSMode.Whenthree satellitesareavilable,2D fixesfor latitudeandlongitudearegiven. If four satellitesareavailable,3D fixesfor latitudelongitude.and altitudearegiven.
LATITUDE/LONGITUDE (LAT/LON) LatitudeiSthediStance measuredin degreesNorth and Southof the equator.Longitudeis the distancemeasuredin degreesWestandEastof theprimemeridianat Greenwich,England.
SPEED OVER GROUND (SOG) This is thetruespeedcalculated from thetime anddistanceoverthegroundyou havetravelledSOG. doesnot considerwaterspeedor destinationfbr its calculations.
COURSE OVER GROUND (COG) This is thetruecourseover thegroundthatyou arccurrentlyheaded.
CROSS TRACK ERROR (XTE) This is thedistanceof your boat, eitherleft or right. from the desiredtrack (startpoint to destination).
ESTIMATED TIME of ARRIVAL (ETA) This is an estimate basedon thecurrenttime andyour TIME TO GO (TTG).
TIME TO (;0 (TTG) This is calculatedfrom thecurrentdistanceto your destinationandyour VELOCITY MADE GOOD (VMG).
VELOCITY MADE GOOD (VMG) This is theportionof your boat'sspeedthatis parallelto your desiredtrack(startpointto destination)VMG. is especiallyusefulfor sailingboatswhereclosing speedon thedesiredwaypointis displayedregardlessof courseor bearingchanges(tacking)madeenroute.
DISTANCE MADE GOOD (DMG) This is theportionof the distanceyour boathastravelledthat is parallelto your desiredtrack (startpointto destination).
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START POINT
N (Trueor magnetic)
coG
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VMGI
DESTINATION
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