Hi, all. Not sure what is going on with my Phantom (Herbert), but I will try to best explain the order of events: - have had around 100 flights so far without any major problems. - last weekend I took Herbert out for a few flights (all in GPS mode). First two went normal, but on the third flight, the Phantom (speeding away, tilting to one side) suddenly started acting very strangely, and I was not able to keep control. Looking at the photos later, it almost seemed as if it tipped on it's side at some point, which would explain the sudden acceleration into one direction. There was power lines in the vicinity here, but not too close by any means. - went home after this and performed an advance calibration. Took him out for another flight after this, and experiences the same thing (on both launches I got the single green light). This resulted in a major crash, which broke a propeller and shell, and resulted in a stuck motor. Looking at these photos, it seems as if it tipped over again. Last night I performed some surgery (new shell, new props and replaced the motor). Just took it out for a flight - green light, hovered in front of me and it seemed fine at first. 30 sec or so into the flight same thing happened again. Out of curiosity, I then tried to fly him in Atti. mode - and everything seemed to work "fine". There was still a bit of drift, but most likely wind and/or slightly bent propellers from the first crash. Also, after the crash today one of the motors now seems to turn with a bit more resistance - something to be worried about? Anyone have an idea what is going on? Thanks! TL;DR: Experiencing out of control/tipping over slightly/resulting in uncontrollable acceleration when flying in GPS mode. Atti. mode seems fine.