Have made 10 completely successful flights in the past few days I have owned the phantom 1.1.1. Have properly updated and calibrated the bird 100%. tonight I went out to show friend and when I plugged the battery cable in it gave me a red and yellow alternating flashes so I did the field compass calibration and it went back green and I got confirmed gps lock and slow green flashing lights. I took off and had it hover in low slow flight in front of us for a minute to explain the controls before I took it up to about 30 ft in a field near the parking lot. I immediatly put it into a fast forward pitch and began to fly a circle and all of a sudden it started to fly away from the direction I was moving it. I realized something wasnt correct so I let go of the stick to let it hover since it was in gps mode. it continued to fly in a random direction. I then fought against that direction and it began to fly back towards me but was still not completely under my control (I do not know what the lights were doing at these moments). then It made a big loop with me fighting it and I was able to make it lose altitude while it was heading into the side of a large building. it crashed into the ground and destroyed the prop guards and nocked the battery from the compartment. I then put the battery back in and it started going through normal start up lights, I did a field compass calibration and took it to the air again. it seemed to fly well but then slowly started flying in a small circle and would sometimes start to drift slowly in a random direction. I just brought it inside and am running a imu calibration now. Im worried as to why it "flew awau" but I maintained some control of the phantom? Is this unit deffective or did I miss something????