Here are some cheats and tips for the game Air Force Delta.
Special options:
Successfully complete all twenty missions under the normal difficulty
setting to unlock a “Special” selection on the options menu. The new
options allow unlimited missiles and the HUD display to be removed.
Bonus fighters:
Successfully complete all twenty missions to unlock the following
fighters: Sea Harrier, AV-8B Harrier II, F/A-18C Hornet, F-15E Strike
Eagle, Su-27B Flanker, Su-34 Platypus, S-37 Berkut, MiG-1.44 MFI.
Successfully complete the game under the hard difficulty setting to
unlock the EE Lighting.