Magellan NAV 5000 User Manual page 146

GQ
GROUND COURSE
GROUND SPEED
HEADING
LAST FIX
LATITUDE
LONGITUDE
MAP DATUM
(highest). A GQ of 7 or better is
preferred, but a GQ of 4 or better
is navigable. A GQ of 3 or below
is inaccurate, and should not be
used to navigate. See Appendix 3
and Error/Warning Messages in
Chapter 6.
Geometric Quality.
The true direction of travel
achieved, which may differ from
courseline. Sometimes referred to
as Course Over Ground.
See Speed Over Ground.
The direction your vessel is
facing, defined as an angle from
North.
The position fix taken before the
current position fix, stored in the
unit's memory and accessed by
pressing LASTFX.
The distance north or south of the
equator, measured in an arc with
the equator being 0° and the poles
being 90°. (The default latitude is
north.)
The distance east or west of the
prime meridian (0°), which inter-
sects Greenwich, England. The
range is 0°-180°E, moving east
of 0°, and 0°-180°W, moving
west of 0°. (The default longitude
is west.)
A method of assigning position
coordinates to real-world loca-
tions. Based on an underlying
ellipsoidal model of the earth, and
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