Servers by jDrones

Servo output stops in FBW modes after GPS lock

(brad112358) #1

After powering on and switching to FBWA mode, I see all the expected servo response when moving the airframe (A small foam flying wing)
Later, a few seconds after obtaining a GPS fix, and immediately after “EKF2 IMU0 is using GPS” is reported in the log, the servos center and no further changes in servo output are observed unless I switch to manual and move the stick. If I arm, the motor runs, but the servos don’t move.

I see the same behavior in RTL and Circle modes. Once the GPS gets a good lock, no more servo output.
This is not what I expected! Why does the autopilot seem to stop trying to stabilize the plane after GPS lock?

I’m currently running on a skyviper V2450GPS board set with code built from clean ArduPlane-3.9.4 source.
I’ve also ported Toy mode to ArduPlane, but this testing was with only Tools/Frame_params/SkyViper-2450GPS/defaults.parm modified from the released code.
I’ve been using and occasionally contributing bug fixes to arducopter for several years but this is my first plane, so please educate me. I must be missing something fundamental.

I have uploaded my defaults.parm file and a log with pre-arm logging enabled for reference here in case the answer is not obvious:

I’ve spent the last few days scanning the Arduplane Docs and trying various things, but I can’t see anything I’ve missed. Can someone clue me in?