Ohh those tank P-51s, barely takes 2 hits with 20mm and it goes down without a wing or other stuff...
Spits.. I see no problem toasting up spits
Though, it is funny how often planes survive from 30mm hit and other times they get blown up whole side of the plane.
I have even witnessed P-51 take 4 hits with 30mm and still it flew and killed.. like nothing would had hit him, also heard another stories of similar kind.
(failing to explode 30mm can't be anymore explonation for this wonder)
About damage model.. I did once lose rear fuselage of my 109 in collision.. eh.. funny huh, nose collision into 50 yards 109...
but I still had every control surface from the tail intact and I didn't see anything unusual in flying, except that i lost also parts of wings (wow, engine was intact, and my windscreen!)
(IMO, i don't like to collide into plane which is 50 yards ahead of me, unless its dragging some ramming wire)
Often these planes have ailerons intact still even though wing is snapped off.