Garmin GPSMAP 238 Sounder - Manual (Page 119)

109
Appendix G
Navigation Terms
position readings.
Off Course— The distance you are off a desired course in either direction, left or right. Also referred
to as ‘cross-track error’ or ‘course error’.
Speed— The current velocity at which you are travelling, relative to a ground position. Also referred to
as ‘ground speed’.
Time To— The estimated time required to reach a Go To destination, or the next waypoint in a route.
Also referred to as ‘estimated time en route’.
Time to Destination— The estimated time required to reach a Go To destination, or the fi nal
waypoint in a route.
Time to Next— The estimated time required to reach a Go To destination, or the next waypoint in a
route.
To Course— The recommended direction to steer in order to reduce course error or stay on course.
Provides the most effi cient heading to get back to the desired course and proceed along your route.
Track— The direction of movement relative to a ground position. Also referred to as ‘ground track’.
Trip Odometer— A running tally of distance travelled since last reset. Also see ‘Odometer’.
Total Average Speed— Average speed of unit for both moving and stopped speeds since last timer
reset.
Total Trip Timer— Total time the unit has been in operation since last reset of the trip timers.
Turn— The angle difference between the bearing to your destination and your current track. ‘L’ indi-
cates you should turn left, ‘R’ indicates you should turn right. The degrees indicate the angle you are off
course.
VMG— Velocity Made Good. The speed you are closing in on a destination along a desired course.
Also referred to as the ‘vector velocity’ to your destination.
DESIRED
TRACK
NORTH
'FROM'
WAYPOINT
NORTH
BRG
TRK
DESTINATIO
WAYPOINT
OFF COURSE
SPEED
DISTANCE TO DESTINATION
188188C238 Manual Part 2.indd 109 6/30/2003, 3:32:49 PM