Raymarine autopilot control unit - Manual (Page 40)

Chapter 3: Advanced Operation 23
change in the opposite direction.
Note: Provided the vessel remains within 0.1 nm of track, there is no
need to steer back towards the track.
Safety
Passage making in Track mode removes the chores of compensating
for wind and tidal drift, and will aid precise navigation. However, it is
important to maintain an accurate log with regular plots.
Position Confirmation at the Start of a Passage
At the start of a passage, always confirm the fix given by the position
transducer, using an easily identifiable fixed object. Check for fixed
positional errors and compensate for them.
Verifying Computed Positions
Verify the computed position with a dead reckoned position,
calculated from the average course steered and the distance logged.
Plot Frequency
• In open water, plots should be at least hourly on sail boats and more
frequently on power boats.
• In confined waters, or when potential hazards are near, plots should
be more frequent.
• Local variations in radio signal quality, and changes in the tidal
stream, will produce deviations from the desired track.
Setting Waypoints
• When setting waypoints, remember that deviations will occur.
• Thoroughly check along each track.
• Check up to 0.5 nm each side of the track to ensure that there are no
hazards within the zone.
General
The use of track mode will enable accurate track keeping even in
complex navigational situations. However, it cannot remove the
responsibility of the skipper to ensure the safety of his vessel at all
times by careful navigation and frequent position checks.
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