"luc" wrote in message
ups.com...
is a rudder angle sensor necessary for an autopilot? I thought the
heading of the boat would be sufficient.

There is no one sentence answer possible. Lots of boats steer to their
owners satisfaction without a rudder angle sensor. Most boats steer better
with a rudder sensor incorporated. Some boats can become absolutely unstable
and dangerous under autopilot control, and in these boats, rudder angle
input is absolutely necessary.
It's hard to go wrong with the sensor, and with many vessels (and
owners), a rudder angle indicator at helm stations is a great docking aid!

Old Chief Lynn