I am having exactly the same problem trying to takeoff from ENGM 01R right now. The aircraft will not unstick after rotate. When I manually slew the aircraft into the air (after five or six takeoff attempts) up to around 6,000 ft, the aircraft cannot hold altitude at all (the closest I could get was a descent of ~1200 FT/MIN).
Aircraft is now completely unflyable.
I've got some screenshots below:
I hope there's a fix soon.