I have a quad with a PX4 FMU+IO combo running ArduCopter V3.2.1 (36b405fb). Lately it has been very unreliable, it suddenly flips or dips hard, naturally causing a crash. I think I have concluded from the logs that the cause is mechanical, but this is my first time really looking at logs for debugging, so I would really appreciate a second opinion…
In the attached log file I tested manual flying for a bit, with no issues,. I then landed, verified that I had GPS lock, took off and switched to PosHod at just past 20 seconds in the log. Shortly after, the copter went crazy and smashed itself into the ground, pitching forward…