I've not actually had any deliberate crashes happen to me yet while playing online, although I haven't played all that many matches. One thing I did notice is that I stacked my plane a couple of times during dogfights because I was using the tracking camera and lost my bearings at low level. Thats not a problem with the game obviously (just bad flying on my part) but it might explain some of the crashing.
As for mid-air crashes.... I can really see that being a problem in strike games. I remember on IL-2 on the PC getting rammed by idiots while flying a bomber...
I've noticed that a lot of people have been asking how to unlock the B17, or to have a Lanc as DLC... thats all well and good, but wait till you've been Kamikaze'd a few times while on a bomb run!!