Engaging AP causes aicraft to pitch

Hi,

have downloaded excellent Aero Commander 500 from Milton Shupe. Aircraft handles great when hand flying, BUT when engaging autopilot aircraft goes first to nose-dive before leveling at AP preselected VSI. Usually only preselect at 900 FPM (but same happens when preselected to 0000). Also disengaging AP causes extreme pitch, which needs to be corrected manually to avoid stall.

Any help appreciated.

Many hanks

Peter

I don't have that aircraft but it might be a trim issue. When hand flying make sure the aircraft is trimmed properly before engaging the autopilot. Hope that helps. I had an issue with a plane that did the same exact thing. I just can't remember which plane it was.

Thanks,

Definitely a trim issue.

Can trim it to zero before flight but the trim wheel goes up and down when airborne, so difficult to zero it again. Got many aircraft and in general all seem to pitch a bit when AP disconnected. Surprisingly Airbuses seem to fly steady following the AP path. Maybe some setting in aircraft.cfg or air file?