While Flying today I came in to land and it would not come down. I was in angle mode, I was about 4" off the ground, I had the stick all the way down. It would not settle onto the ground. It was drifting and I had to keep bringing it back to the landing area. In the end I had to hit the STOP button and let it fall the 4" a GPS Error registered the second it hit the ground. Software is up to date, Compass was calibrated prior to flight and Accelerometer was calibrated on 10.2.16 when I completed the software. Still trying to figure this birds quirks out. Any input would be helpful. This is my 4th battery and second issue with this unit.