I'm running into the same problem. About 2 months ago I was able to fly helicopters. Now, I can only fly airplanes. I've uninstalled & re-installed both 2.0 beat 7 & alpha 8.5. Neither version works with helis.
Other notes:
I have used 3 helis that came with FMS & also copied in 1 other. I've tried using several different landscapes in various combinations with helis.
Has anyone found a solution to this?