Simrad Robertson AP9 Mk3, Instruction Manual, Page: 36 / 202

Robertson AP9 MK3 Autopilot
2-8
20169223D
COUNTER RUDDER
The COUNTER RUDDER
serves two purposes, firstly
to give a smooth transition
to a new heading after a
major course change has
been made, and secondly
to enable the autopilot to
stabilize the vessel on a
straight course. The
steering characteristic of
the autopilot is determined
by the RUDDER and the
COUNTER RUDDER
adjustment.
The effect of the Counter
Rudder is partly deter-
mined by the selected Turn
Rate, hence tuning the
Counter Rudder effect also
involves the Rudder
Control.
A too low value results in an overshoot past the new heading and it
takes a long time before the new heading is stabilized.
A value that is too high results in an over correction followed by a
small overshoot past the new heading, and the vessel then tends to
oscillate around the new heading. A typically symptom here is an
over active-rudder.
Range: 0 – 8.0
Recommended start value: 0.6