Just started descent in the 350 in managed mode (FL360-FL130).  All normal, then aircraft still in managed mode (AP on), suddenly went into uncommanded high rate climb .

Disconnected AP, re-established descent (on green dot), then all returned to normal.  No apparent reason for the sudden climb.

Hi,

That is a very odd issue. I'm afraid will need more information than that to tackle this.

In case it happens again please take screenshots of your cockpit showing the PFD,ND, EWD and FMS F-PLN & PERF pages so we can get more clues as to what may be happening.

Personally though, that isn't behaviour I've experienced as yet in the 300+ hours of flying the A350 so far.

Thanks! 

On 3/10/2025 at 3:48 PM, richboy2307 said:

Hi,

That is a very odd issue. I'm afraid will need more information than that to tackle this.

In case it happens again please take screenshots of your cockpit showing the PFD,ND, EWD and FMS F-PLN & PERF pages so we can get more clues as to what may be happening.

Personally though, that isn't behaviour I've experienced as yet in the 300+ hours of flying the A350 so far.

Thanks! 

Thanks and yes, will do if I get the chance again.  agree,  most odd.  Flew yesterday without issue at all, although I must say AP disconnects during cruise on occasions.  Again, Managed Mode and no inputs being made anywhere.  It simply disconnects, but is easy to re-connect.

Edited March 11, 20251 yr by Transair

That sounds like a possible keybind conflict (inadvertent inputs on Aileron/Rudder/Pitch or trims for either of those). Check your control profiles and ensure none are bound on any connected devices other than the one you want.

Additionally, you may use the AP DISCONNECT PROTECTION option from OIS Simulation Settings which inhibits the realistic AP disconnection logic (due to control inputs or excessive rate of change on g forces)

Thanks!

thanks again.  I do have a yoke plugged in as well as the joystick, but to date I don't think I've had conflict between them.  Also, there was no input for any axis/trim, with the yoke at the time. Still....maybe a thought.  I do like your disconnect protection though, and will enact that.  thnks again

Edited March 11, 20251 yr by Transair

Hi again

to follow on....I did as you suggested and set AP not to disconnect, but it still does.

I got this uncommanded climb again.  Note AP disconnected/AT disconnected and even with descent to FL210 in the window and no other input, the a/c climbed....Initially at 5000fpm, and I got a warning 'AP in Protection Mode' on PFD - just couldn't capture that in the photo....seems all related somehow.  Hope this is helpful for you..