I’ve just completed a new TBS Discovery Pro build and went for first flight and autotune session. The flight was clean from takeoff, roll autotune has completed, then I switched to LAND to change the battery. The copter landed, and then took off again, went to the side and flipped. As you can see from the log, neither landing detection nor crash detection worked properly and I had to disconnect the battery with motors still spinning. I hit the left stick to disarm position when it took off again and held it there, but that did nothing. Can anyone please help me understand the problem?
Frame: TBS Discovery Pro quad
FC: 3DR Pixhawk
Log file: https://drive.google.com/file/d/0B3-JjJykr-BdRmJjMDFXY2RGZGc/view?usp=sharing