I was just flying my hexacopter and after initial rising to about 100m it was hovering there. About some 10s of seconds later, it started to fly with high-speed away. It turned around and flew above me in the opposite direction, again with high-speed. In QGC i saw where it was and i switched to RTL (geofencing - 200m should have had done that already). But instead of slowing down and landing it flew crazy around. After it came back, I disabled all motors by hitting emergency off button. The drone dropped out of the sky. I found it. One of the F550 arms were broken.
Broke it in mid-flight? Was that the problem? GPS-Tower was also broken two times, but that was the result of the impact.
How high was it when I stopped the motors?
Logs are here: http://logs.uaventure.com/view/2v43qn7Ri6gANZ9dcX4n47
My configuration: F550, Pixracer, PX4-Version: 1.4.1dev
Thanks for your help!