If you have use LFS Tune, you will know that the car will reset if it faster than 200m/s.
http://hk.youtube.com/watch?v=EqxcbUuXn_0
It's to stop you flying away into oblivion if a collision goes a bit madder than usual.
but I don't think that it is useful, because I also saw many people flying away. so, I hope that it could be canceled.

Quote from scania :

It's to stop you flying away into oblivion if a collision goes a bit madder than usual.

No, it's not. It's because the physics engine runs at 100 Hz, and it just can't process information if the car is going faster than that speed iirc.

what is iirc?

Quote from scania :

what is iirc?

If I Recall/Remember Correctly