I got EXTREMELY lucky that it landed unharmed.
The imu calibration should be done at home on a completely level surface ..Have the Tracker, though it was in my pocket during that flight (I guess I could track my pants at least). The compass does point correctly after my last calibration though it does seem a little off. The direction is good. I had completed a short flight just prior to that one on the same battery. Does that matter?
Prior to that flight I calibrated the IMU at that location. The surface may not have been perfectly level. Learned my lessons though. I was just wondering if experienced pilots think that flight track was caused by compass error. It also went to 500 ft on its own. I'm positive that it was at 350 when I lost complete control.
Thanks for your input and information, looking forward to learning as much as I can about the aircraft.