Passed the mission 100%.
Very hard mission.
Only managed to pass using cheats - endless weapons and labels. Helicopters are very difficult to detect (labels to help) and no less difficult to shoot down (missiles go to the flares and not enough ammo). To get a hit and a voice message to shoot down a helicopter, I launched the P-60 many times, and added a gun. Also, helicopters can take a lot of hits from the gun without being shot down.
Regular ammo would obviously not be enough.
суховей's post in M12 CAP over Pshada (with helos) was marked as the answer