BeBro, this is a link to a People's General forum that has posted the read me. You may be able to find more info there.
http://pub131.ezboard.com/fjpspanzer...icID=364.topic
The following is a strategy guide link.
http://www.wargamer.com/articles/peg...gy_guide2a.asp
2.3.2.5. Air Superiority Adjustment
You can adjust the air superiority percentage at the beginning of each scenario in the campaign. The decision to make the adjustment should consider the following points.
What else do you need to spend your prestige on? Raising the air superiority level is usually quite expensive. If you adjust the air superiority level, can you afford to do any thing else?
Is it really worth it? Upgrading the air superiority level is applied for that scenario only. If you spend your prestige on buying, upgrading, or overstrengthening a unit, you will have the benefit of that purchase for the rest of the game, assuming the unit is not destroyed.
How much do you depend upon air power? If your combined arms team utilizes air power as an integral element, then the cost can be justified.
I hope this helps.