imo as far as this game is concerned, there's no need (or ability) to 'qualify' for Night air ops. also, Training in Night mode is v. slow.
's a bit weird, in that non-NF fighters are hopeless for Night Cap, but NF sqns are unable to train 'Escort' during daylight.
i populate my NF sqns w/ fully-trained high-exp pilots out of the Reserve or TRACOM pools.
based on my experience w/ the Downfall scenario, when my current AI-game gets B-29s, they'll be doing quite a lot of Night strat-bombing & airfield attacks. their pilots will be the best i can find, their HQ & sqn leaders will be top-notch, & i'll be spending no few PPs to align their bases, AirHQs & sqns to a well-coordinated command structure.
Night fighters can train on "sweep" during the day which will increase the air skill.
As far as non-night fighters being hopeless. Quite frankly, I have yet to see any difference between radar equipped night fighters and regular fighters on CAP. I would not waste any time or thought on night fighters. Any fighter unit put up on night CAP will not shoot down much but they do affect bombing accuracy. Night fighters don't seem to be any better at this that regular fighters.
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