Instead of some possibly unreliable "if they miss" detection on moving vehicles at very long distances and trying to hit a plane with a single bullet (Get Kaje's sniper rifle, that's the speed limit on projectiles) it could fire a wide spread of that each explode when you release the 'fire' key in mid-air. This makes it a big deterrent for planes to get near. I'm not sure how much damage it should do though, as such a weapon would really devastate ground troops too.
Maybe more damage to vehicles?
AND we could make AA missiles, with your Homing Missile script, but make it lock onto vehicles instead.
