[HGabor]

True, but in a dogfight, or fighter attack the speed difference between the two planes was not significant, as the attacker usually followed (pursued) the victim, having a much better situation for aiming. Plus even smaller caliber ammo (from multiple guns with high firing speed) could set an aluminum plane on fire much easier than a steel tank, which required precise hits with larger ammo - obviously from larger weapons having slower firing speed.
Also, for ground targets, the speed difference between the attacker and the ground target was several hundred km/h (much bigger than in the air), giving a much smaller chance (shorter striking time) to score an efficient hit - if the pilot did not want to crash into his target. Two completely different situations, I would not even compare the two!

Gabor