My new Phantom 2 crashed after a prop spun off yesterday. I lost one motor, all the props and the H3-3D gimbal doesn’t work any more. After investigating the unit, and checking the Tiger Motor website, I found that the four motors were installed backwards. The counterclockwise motors are where the clockwise ones are and vice versa. The wiring was done so they rotated in the correct direction making the Phantom flyable, but the threads on the propeller nuts would spin off the nuts - causing the propellers to fly off. Normally, if installed properly, the would be self tightening. In this case they were self loosening. You can check here http://www.rctigermotor.com/html/2013/news_0906/7.html if you want to check Tiger's installation instructions.