helicopter freeze

[RodgerP]

When I fly a helicopter in FSX, it is very likely to freeze the program after a few minutes' flight. I have reloaded FSX from scratch but still it happens. No error messages are displayed, the program just freezes. The sound still works. Any ideas?

[OldAirmail]

Just a WAG.

It might be a conflict with DX 10?

[RodgerP]

Thanks for the thoughts! DX10 is disabled. I do have five helos from the 2004 era. Someone has suggested that they may be part of the problem, but I don't know how to track that down. All suggestions are welcome!