AUTOPILOT
1.1.5 P2, Damping of compass heading [SEA]
Possible settings are [0] = Minimum to [9] = Maximum.
Set by the APC routine.
This setting is a combination of yaw dead-band (compass
sensitivity) and compass damping. The minimum setting may only
be used under calm sea conditions to avoid unnecessary rudder
correction due to compass acceleration errors.
Smaller boats and high speed boats, which are subject to more
acceleration in lighter seas will have to use higher settings. Larger
and more stable boats can use lower settings since there is less
compass disturbance.
Default setting should work on most boats in light to moderate sea
conditions. Following seas, no matter how rough, may require lower
settings to catch course error trends quickly in order to minimise
excessive yaw.
6.3.3 P3, Counter Rudder [CRD]
Possible settings are [0] = Minimum to [9] = Maximum.
Set by the APC routine.
This setting senses the rate of change of heading and gives
additional rudder corrections if the boat is rapidly falling off course,
and backs off the rudder as a boat approaches the desired
heading. Its effect is to rapidly catch the tendency to yaw in a
quartering sea, provide initially high rudder control when making a
large course change and to decelerate the swing of the bow, as a
boat approaches the desired course.
Course holding with heavy and difficult to steer boats, is greatly
improved , when using this feature. Too little counter rudder, will
allow the boat to overshoot on large course changes. Too much will
cause unnecessary rudder corrections and a tendency to stop short
of coming to a new course, requiring several successive corrections
before easing up to the new heading.
To optimise counter rudder, initially set it to minimum and adjust the
rudder (see, [RUD] 5.3.2). Increment the counter rudder one step at
a time, while testing 40
° course changes, until the boat achieves an
overshoot of 1
° to 2° or less. Remember, that any air in the
hydraulic system will prevent precision control.
6.3.4 P4, Damping of wind [WSE]
Possible settings are [0] = Minimum to [9] = Maximum. Default
setting is [2].
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