Auto Pilot Fails When Cold

[Bob Cook]

Dale

Problem with autopilot is probably the servo's. If we are dealing with the pitch servo then it is probably the pitch trim servo. Either the clutch is slipping or the motor cannot overcome the stiff grease in the servo. There is a proceedure in the manual which covers lubrication and checking of the clutch tension. Wrong type of grease or OLD grease can cause this problem.

1(Does the autopilot disconnect with the sw on the control colomn?
2)does the main power switch (rocker) drop out at anytime?
3)do you see any movement of the pitch trim after it starts to act up?
4)does the rest of the AP work okay? (roll axis)?

I am suspecting the pitch trim servo and not the elevator servo. This is the one in the pax side rear boom.

If you do not have a manual I can email you the proceedure to clean and adjust by your mechanic.

fyi

bob