During cockpit prep prior to takeoff, the Autobrake switch will not stay in the RTO position > it returns to the off position.  Setting the autobrakes while in flight

(for landing prep) functions normally.  This is a very recent development.  Any ideas regarding what may be causing this will be appreciated.

Best to all,

Ken Boardman

Are the engines running , hydraulic pumps on ?

I believe that the aircraft has to be stationary.

I sometimes find my (saitek) throttles catch the reverse range, and as soon as that happens, the RTO disconnects. Sometimes they just crack open. That said, since SP1/SP1b it will also cause the V1/VR/V2 speeds to go blank.

 

On a similar note... do you have hardware rudder pedals?

Are you unintentionally sending input to your brakes?

I have CH Pro pedals and I think that they may somehow be a factor; but I'm not sure how to confirm / correct the issue. Perhaps changing

a setting (null, sensitivity, etc) ?

Thank you for the responses.

Ken

You can test by disconnecting them to test, but that doesn't obviously fix the issue (just disconnects the pedals).
Ramping up the null zone on the brakes sounds like a good starting point..