There is both air to air combat and self-propelled anti-aircraft artillery in the Amerika game. The way it works is as followed;
1. Phase 1-Anti-aircraft Artillery fires (both sides). Casualties removed.
2. Phase 2-Air combat. Fighters are matched up with fighters, extra fighters can double up or wait and take part Phase 3 (ground combat). Bombers are matched up with bombers, extra bombers can double up or take part in Phase 3.
3. Phase 3-Ground combat. Any aircraft not engaged in Phase 2 joins in the ground combat. Remove casualties. End combat.
Note. Fighters are matched with fighters first and bombers with bombers first, but if one side has more fighters and the other more bombers, then fighters are matched with bombers. On a
D12, fighters hit at 4 and bombers at 2. There are only the 2 types of planes and there is only 1 round of combat.
What I would suggest if you wanted to adapt some type of system like this is that you keep the AAA already in A&A (reduce to 4 IPC) but add SPAA for 5 IPC and only the SPAA could move on combat movement. Or if you wanted just convert them all to SPAA.
First round-AA fire. Remove casualties. Match the fighters with fighters, tacs with tacs, any extra with strats but no strats vs strats. Assign values to them eg. F=2, TB=2, St=1.(or something like that). Remove casualties.
General combat with any leftover aircraft at normal values. Remove casualties.
Second round-back to regular combat. Continue to resolve combat.
I think that you will find that the planes will disappear faster than in an OOB game so be careful what you wish for if you want air to air.
The combat is certainly a lot more interesting in Amerika. General combat has different categories where you can target higher value units with other higher value units or with good rolls. You wouldn’t be able to adapt it to A&A without completely changing the mechanics of the game so if that’s something you wanted to do you may as well invent a new game or go and buy yourself an Amerika game.