First...what I had.....originally I set Tana Mari up (44 feet on deck, 36000 lbs with some supplies) with a wind vane.....worked reasonably well...except if the wind shifts the autopilot follows the wind...maybe when you are sleeping...and guide ya right onto the rocks. My wind vane was small and operated a trim tab purposely built and faired as part of the outboard rudder......
I replaced it with a small electric autopilot designed for a 30 foot lightweight plastic weekend sailboat......the trimtab thinks it's the rudder....
I don't know anything about your friends boat, outboard or inboard rudder......BUT...if he can make some changes to the rudder by adding a trim tab, and perhaps if the rudder shaft is hollow, the drive for the tab can be worked through the rudder shaft, an inexpensive autopilot may work just fine. The electronics in the big monsters and the little ones are generally the same....just the massive drive motor transistors and the linear actuator drive get to be really costly.....
Wakan Tanka Kici Un
..a bad day sailing is a heckuva lot better than the best day at work.....
Fighting Illegal immigration since 1492....
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