WWI saw the first widespread use of aircraft in battle. It's something to remember that powered flight was achieved only a few years before the conflict broke out. WWII really saw aircraft come into their own. No longer just a novelty or a side-act to the ground battles, aircraft were a major part of the war effort, with thousands of planes being used by all sides. However, that aspect is often lacking from WWII miniatures games. Well, Warlord Games is looking to bring it to Bolt Action and they've posted some experimental rules to test the waters of it.
Obviously, like any wargame, the rules have to be abstracted to fit the constraints of playing on a table using models that are much more static than they actually would be in real life. So things like high-altitude bombing runs have been left to the "artillery bombardment" section of the rules. And shooting at planes also is a bit different than it would be actually on a battlefield. But if you want to test out the rules, they're there for your enjoyment.