Interested to see if any one has experienced my problem. Recently I went to fly my FC40 and decided to attempt to fly again after a fly away experience a few months ago. After much thought I came up with a reason for my last fly away so I wanted to test my theory. So I went to a secluded area away from civilisation. Set the FC40 up with the factory props and it flew perfectly. I recalled on my last fly away that I was keen to test some new props out. So I tried them again. And the same thing happened. On take of it just went straight up with no control, flew for about 300 meters and just descended and crashed. My original thoughts were no home lock, but I made sure I had the correct start up before lift of, These props were purchased as Phantom 2 props which had work ok previously. Only difference was these were white props and the previous ones I used were carbon Fibre. I have inspected the blades and they appear to be similar.