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10
Great Circle Navigation
The great circle navigation algorithm calculates a course line that is the shortest path be-
tween two points on the surface of the earth. Using this navigation algorithm, course to
steer when navigating towards a waypoint is not constant. The resulting track of this nav-
igation algorithm will differ from the straight line drawn on a Mercator projected chart.
Rhumb Line Navigation
The rhumb line navigation algorithm calculates a course line that corresponds to a straight
line on a Mercator projected chart, and cuts across all meridians at the same angle.
Waypoint Pass Criterion
The criterion used to determine when a waypoint in the active route is considered passed.
The waypoint pass criterion can be any of
Manual, Distance, Bisector Line
and
Perpen-
dicular Line.
Manual Waypoint Pass Criterion
Using this pass criterion, the waypoint is only considered passed when the operator skips
the waypoint.
Distance Waypoint Pass Criterion
Using this pass criterion, the waypoint is considered passed
once the ship has reached an imaginary circle around the way-
point. See illustration to the right. The radius of the circle is
configurable.
Bisector Line Waypoint Pass Criterion
Using this pass criterion, the waypoint is considered passed
once the ship has reached an imaginary bisector line of the an-
gle between current and next leg. See illustration to the right.
Perpendicular Line Waypoint Pass Criterion
Using this pass criterion, the waypoint is considered passed
once the ship has reached an imaginary line perpendicular to
current leg. See illustration to the right.