[Skullbiscuit]

yes, I think u r right, it could well be a missile debris impact. Still, the damage distribution done by a high rate of fire machine gun like the russian one would look quite similar to this IMHO
It would be nice to have a post with all the aircraft damage picture we can find, to use as reference, don't u guys think?

Sure would help to have photos from that era...of course. You may want to search the SIMHQ IL2 archives for photos on this subject. It has been covered before and other folks have already posted photos there representing select types of damage. I don't know how the game engine models angle of entry...but that has a significant effect on visible tears in the skin of the aircraft

SB