Had a flyaway with my quad today. This is a scratch built model with NAZA Lite, GPS and DJI E300 propulsion kit. I have had dozens of successful flights with this quad and hundreds with my Phantom 1 before it. I took it to a location where I have flown the Phantom a few times before. Went through my normal startup checks. Quickly got 6+ satellites and set home position. Manually reset home position to be sure. Lifted off and right away it seemed to be drifting and not holding position. I brought it down and did a compass calibration. Launched again and again it started drifting. Tried to land but it took off like a rocket about 50 feet away and dove at an angle into the ground. Fortunately it did not hit anyone or damage any property. I had to climb under a high chainlink fence to retrieve it. Damage to the quad was minimal. It broke 3 of the 4 legs which were 6mm cf tubes and snapped the mount for the GPS tower. Brought it home and cleaned up the damage. Hooked it up to the NAZA assistant and checked everything. All looked normal. Recalibrated IMU and transmitter anyway. Now it seems to fly fine but I am hesitant to trust it.