The enemy won’t want to trade fighters and bombers for subs and therefore won’t attack your fleet to begin with. Subs can’t attack planes thats the problem! you can;t let subs take hits from planes… if they could that would be great!
No but they can attack the floating landing field the planes land on…everyone talks about how subs can’t hit planes like its a weakness -its a strength- being able to force my enemy to take hits on ships instead of realitively cheap fighters is a plus!
However, I think that they are too much details for a light wargame like A&A.
There are a lot of things that are different from the real world and from the real History in A&A.
Simply I do not feel the needs for them i nthe basic rules set. Thay could be fine house rules.