Per HT about a thousand times (hyperbole), if you are involved in a collision, and only receive a "PlayerX collided with you", and not a "You have collided" message, and you took damage, you took it from guns, not the collision.
I've been in literally dozens of collisions in the recent past (I can only surmise that all the new subscribers and 2weekers are learning about our collision model the hardway), and while the parts I lose sometimes amaze me (flaps in a 109? tailwheel? what's a tailwheel? hell, what are flaps?), it seems to be working pretty well. I get a lot of kills from guys plowing into the back of me, while I'm often lucky enough to take just a few gun hits and continue fighting. Free kills are good, right?