Ace level AI bombers regularly crash into each other when maneuvering in formation, at least on the Bessarabia map and when setting up QMB missions.
On a similar note, often the third plane in a four plane formation will arbitrarily go into a very steep dive of at least 300 m, then climb to rejoin the formation, possibly to avoid collisions.
By contrast, rookie AI never seems to have this problem, perhaps because they're either slower to react to nearby planes, or because their formations aren't as tight.
I don't know if this is a QMB problem or an AI problem.
In either case, the cause of the problem seems to be that the AI isn't "thinking ahead" far enough to accommodate the very tight turns built into the AI flight paths created for QMB maps.
The quick and dirty solution would be to set QMB AI flight paths so that the turns are much gentler.
The better solution would be to alter AI formation behavior so that the formation "opens up" prior to a sharp turn, with planes on the outside of the formation speeding up prior to the turn and turning later to keep station, and planes on the inside slowing down and starting their turns earlier to keep station. Alternately, planes in formations of four could "cross over", so that the number 1 plane in the formation becomes number 4 and vice-versa. (Not always historical, but it works.)
http://forum.1cpublishing.eu/attachm...1&d=1405747271
Screen grab of two Ace AI Wellingtons about to collide.
http://forum.1cpublishing.eu/attachm...1&d=1405747840
Oops!