Had my first major crash the other day when the quaddy was flying around in auto mode. I had originally told it to fly out to the center of a field, spin 3 times and then do a circuit around the field. But at some point when it was near the center of the field, the GPS acted very strange and the quaddy didn't know what to do with it self, so it ended up racing towards a tree and slamming into it.
I'm using APM 2.5+ with 2.9.1 http://store.diydrones.com/APM_2_5_Not_Assembled_p/br-apmpwrkt2.htm
And a 3DR GPS uBlox LEA-6 http://store.diydrones.com/3DR_GPS_LEA_6_p/br-3drlea-6.htm
Logs of the event can be found in http://users.on.net/~infernoraven/quad/ (note the video in there is of another crash, but feel free to download it. 1080p 60fps first person gopro cam)
I have tried looking through various graphs of the logs, and cant really work out how to diagnose this issue so its less likely to happen again.
If you replay the log file, you'll see that the quad is on a field next to Canberra Technology Park at lunch time. I do 3 major flights.
1st - Just a simple fly about and guided mode to a waypoint and back
2nd - follow a set of waypoints in auto mode around a field
3rd - Fly to center of field and then follow lots of waypoints around edge of field (this is where things go wrong)
At about the 85% mark of the the log replay, you'll start to see the quad make its way to the center of the field, but then suddenly go south, and then zoom north very fast. But the GPS positioning doesn't update as often as it should. GPS wise, it actually tells the quad its under ground.
What I actually saw during flying, was that the quad got to the middle of the field and had a hard time holding position, it did NOT appear to spin around 3 times. It then drifted a little way and went full tilt towards the north into a tree.
If anyone can decipher what went wrong it would be really good to know.
Note: Quaddy is fine after it fell out of the tree, just some slightly busted props and a damaged motor from what I can tell.