I once had something really weird with the cloud car in Bespin: platforms. I was flying around a bit when suddenly a x-wing flew in to me. The x-wing exploded but I survived, but the most odd: the head of my player was smashed through the cockpits nose. After about 30 seconds my head 'popped' in again. Did someone had the same problem?
p.s. This happened in the ps2 version
I have never had it happen in your scenario, but if I am infront of a vehicle (enemy) and I am any unit attacking it, if I get hit pretty hard, my shoulders or weapon will stay in a spot and I will fly off. It is usually when two things are moving at a high pace and then one stops and goes flying in another direction.