Hi,
Are you using an ATI card?
I was having what seems like the same problems you are having. Very often, I would get a black screen for about 3 seconds after the loading screen and then the game would crash thus initiating reboot. On the few occasions I did get the game to run, it would eventually crash and force reboot after about 10 minutes of flying... same as you.
Anyway, I went to the ATI website today and updated my video drivers. That seemed to cure my crash problems. I don't know if doing that would help your situation, but it might be a good idea to make sure your video drivers are up to date.