Near the end around 30-20 more minutes left, there is a dogfight scene. We do see a few B-17 Planes exploding. No gore, but there is a scene where is a scene where a Pilot remarks about the heavy Flak then they unexpectedly explode. No blood, no gore.
While this is a "war movie", there is actually very little violence. Most of the battles are only "talked about" and not actually seen. The few scenes of planes actually in battle consist mostly of stock footage from actual planes in combat. This footage is black and white and not in the best of shape, so even it is fairly tame.