This is great! Thank you very much!
This should sort itself out if you have enough pilots and the airgroups are in supply. You dont need to do anything manually (but check pilots).
What do you mean by checking pilots? Should I transfer them somehow? How does this work?
When you look at the commanders report (c) -> airgroups the third-to last column shows you the number pilots in the airgroup (plt). If there is a "*" symbol it means the group is not at capacity. You can then add pilots, either to all selected squads (depending on your filter settings) via the symbol in the top right of the commanders report ("Add Pilots"), or individually for each airgroup via the airgroup screen (add max pilots or add pilots).
Regarding recon, I see that many of my squadrons have few airplanes left. Take the one flying the F-9 Fortress for example. It has no more than 3 aircraft left. It has too few aircraft to fly at all. Trying to change the aircraft type I can not find any to replace them with. What should I do with this squadron? Can they not get a few "regular" B17?
Yeah that's what I meant, all your American recon squads have been ground down pretty heavily and you now have to few recon frames overall, so switching aircraft types around wont help.
You will be getting some B-17 converted to the F-9 over time, but bluntly this will take a while to recover from. In the meantime there is little you can do, but try to tax the American squads a bit less: Fly in safer areas, use brits for more dangerous missions, fly on fewer days and only in better weather, use more escorts. All of this should lead you to more sustainable levels.
Just a couple of further notes:
-Note that airgroups are out of action for a turn when you switch air models. Thus try to time that correctly, e.g. when weather is bad or the groups have low morale or high fatigue.
-When you switch to a plane with a different number of engines (e.g. Spitfire to P-38) you loose some experience. Not great, not terrible if done once, but dont do it every other turn.
-Remember its not just about losses, but also upgrades. For example you still have plenty A-20B to replenish the losses, but you might still want to switch to the A-20G-K model since it will have better performance (That 4x0.50cal nose for the win!)