QuadPlane Full Pitch Flip in Transition from VTOL to FW – Near Crash

ArduPlane Plane 3.8
5

Hi @tridge,

Tlog File: https://we.tl/roqXFLauuW

  • Wing twist: Body and wings are full composite and very tightly fixed. So I dont think this as a problem.

  • Voltage Sag: Voltage at the time of incident drops down to 20.5V instantaneously. But I dont think this is the problem, since I had successfull auto flights with battery voltage down to 20.2V.

image.png1495×896 23.3 KB

I checked my “.tlog” file and found similarity to @GregCovey’s incident (QuadPlane Pitches Up using v3.8.0 beta 5). Logs show that high PWM commands (same PWMs to both motors) are applied to forward VTOL motors prior to pitch up.

image.png1491×903 37.1 KB

@GregCovey experieced the similar situation at the end of the transition maneuver (in my case at the beginning of transition), with 2 motor recieving same PWM commands causing pitch up maneuver.

Capture2.JPG934×434 55.5 KB

Best wishes,
Ferit.