I haven't noticed problems with the gravity model myself. Just the other day I was messing about in a jet (trying to get a screen shot for that other thread) and I accidently clipped my belly on the ground trying to pull out of a dive. It was the most gentle of collisions but it made the camera move out with the "Crashed. X to continue text".
But the jet was just gliding along at an altitude of about 20m. I just had to sit and watch and wait for it to hit the ground. 35 seconds it lasted in that unmanned glide
