Autopilot disengaging uncommanded

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george
Posts: 11
Joined: Fri Sep 07, 2018 8:07 pm
Autopilot disengaging uncommanded

Post by george » Thu Sep 26, 2019 9:07 pm

Any suggestions as to why autopilot won't engage?

JonathanBleeker
Posts: 3446
Joined: Sat Mar 13, 2010 7:38 pm
Re: Autopilot disengaging uncommanded

Post by JonathanBleeker » Fri Sep 27, 2019 8:48 am

The 3 SAS switches on? Within pitch/bank limits?

Oh the humor of your handle and the subject of this post.... :lol:

george
Posts: 11
Joined: Fri Sep 07, 2018 8:07 pm
Re: Autopilot disengaging uncommanded

Post by george » Fri Sep 27, 2019 2:17 pm

Hi JB,

All SAS switches are on, acft well within flight envelope including speeds. Checked circuit breakers, etc. I think it may be a bug. I also noticed that the Tacan setting from a previous flight remains; in the past the Tacan setting would go back to original setting within the sim.

Years of fighter and commerical aircraft maintenance training and flight engineering taught me that typically autopilot disengages when manual input is sensed beyond throw pressure limits of the stick.

With SAS engaged to your point, the aircraft is supposed to hold an attitude given a certain stick input. If it were a real aircraft, and given the F-4, I'd sense it may be stray voltage, stick sensor or a bad CADC. I've seen a real F-4 eject three external tanks on the pad after the pilot turned on the generators. Ever seen a pilots eyes through his sun visor when that happens, ha ha!?


As for my handle, it has nothing to do with George AFB although I did work on Phantoms back in the day. Ha ha!

That handle was given to me by my parents, but I do see the humor.

Thanks for the quick reply.

Cheers,

George

F-16A/B/C/D, F-4G Phixer-C-141B Flight Engineer, 737NG Instructor.

JonathanBleeker
Posts: 3446
Joined: Sat Mar 13, 2010 7:38 pm
Re: Autopilot disengaging uncommanded

Post by JonathanBleeker » Fri Sep 27, 2019 2:26 pm

Does the AP Master switch flick back to the off position immediately after clicking it?

And no the humour is more how autopilots are often nicknamed "George".

george
Posts: 11
Joined: Fri Sep 07, 2018 8:07 pm
Re: Autopilot disengaging uncommanded

Post by george » Fri Sep 27, 2019 3:09 pm

Exactly, the switch cycles back. Have you seen that before?

george
Posts: 11
Joined: Fri Sep 07, 2018 8:07 pm
Re: Autopilot disengaging uncommanded

Post by george » Fri Sep 27, 2019 3:10 pm

First I've heard of autopilot being named George; I guess my folks must have had a vision for me, ha ha!

JonathanBleeker
Posts: 3446
Joined: Sat Mar 13, 2010 7:38 pm
Re: Autopilot disengaging uncommanded

Post by JonathanBleeker » Fri Sep 27, 2019 3:21 pm

Do you have it assigned to a joystick button in the MVAMS?

george
Posts: 11
Joined: Fri Sep 07, 2018 8:07 pm
Re: Autopilot disengaging uncommanded

Post by george » Fri Sep 27, 2019 3:26 pm

I do.

JonathanBleeker
Posts: 3446
Joined: Sat Mar 13, 2010 7:38 pm
Re: Autopilot disengaging uncommanded

Post by JonathanBleeker » Fri Sep 27, 2019 4:27 pm

Is toggle enabled on it?

george
Posts: 11
Joined: Fri Sep 07, 2018 8:07 pm
Re: Autopilot disengaging uncommanded

Post by george » Fri Sep 27, 2019 4:58 pm

That must have been it. I enabled toggle and it works. Thanks JB; well done.

Cheers

George

JonathanBleeker
Posts: 3446
Joined: Sat Mar 13, 2010 7:38 pm
Re: Autopilot disengaging uncommanded

Post by JonathanBleeker » Sat Sep 28, 2019 5:52 pm

Yup. If toggle is disabled it sets the AP to the state of the button. Useful if you have a physical switch that isn’t spring loaded.


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