This mission is weird.
I got all training missions done the first time I flew them (except for the level flight bombing) but this 'dive bombing' mission is incredebly hard.
First dive bomb a factory. Easy. Then strafe a whole airfield to ground?? Besides the amount of ammo needed (if you have realism HARD) is too much, but mostly there is too much anti-air flack. If I take down the anti-air's (like i did in CFS 1 and 2) I will have no ammo left. If I dont, I get shot in no time.

When I started a campaign, in the Hard seting, I found the missions very easy to handle and the flack much more forgiving. Maybe it's cause I'm only in the 5th or 6th mission.