Auto Pilot Disconnect

[rfazio1951]

I have been having the auto pilot switching off on me during flights recently. It switches off with the announcement, "autopilot disconnect". Then last night it disconnected, and I got a message that the auto pilot servos were unavailable. I could not get them to work and flew the rest of the short flight by hand. Once we landed, I shut down the system and rebooted it. The servos were back online working fine. Any ideas??

 

[Carl_Froehlich]

What were the condtions of flight - as compared to whatever you set for autopilot minimum and maximum air speed?

Carl

 

[rfazio1951]

It was in the evening with very calm conditions. I was in cruise at my normal speed, 150 knots. We were flying IFR for a 30 minute flight. My min and max speeds in the autopilot settings are 90 and 210 if I remember correctly.

 

[airguy]

Servos unavailable could be a power issue, check power and ground.

 

[jakej]

Richard - having both servos disconnect is unusual as I’m sure you would have independent power to each ?
Do you have the ‘disconnect’ resistor/s installed ? ( FWIW) I never install those & haven’t had any requests to add them.
Is your AP Panel affected by the Service Bulletin ? (had to ask).

 

[rfazio1951]

Yes i have two breakers, one for each servo. A disconnect resistor? NO. AP panel? I have to check. Thanks for the info, i‘m on it.

So, the disconnect resistor seems to be for disconnect switch failure? I have to look into that. The AP service bulletin is for the auto trim feature. I do not have auto trim connected. I’m using manual trims.