When landing your plane, look for blue rings floating near where you are landing. Use your airbrakes to slow down your plane and fly through the blue rings. This will cause your landing gear to deploy.
Unlock the following Aircraft by beating the corresponding bonus objectives on the specified difficulties:
AIRCRAFT - HOW TO UNLOCK F-15 Eagle V1 - Mission 1.3 on the Rookie difficulty setting. F-15 Eagle V2 - Mission 2.3 on the Pilot difficulty setting. F-16 Falcon V1 - Mission 1.3 on the Rookie difficulty setting. F-16 Falcon V2 - Mission 2.1 on the Pilot difficulty setting. M-27 Flogger V2 - Mission 1.2 on the Pilot difficulty setting. MiG-27 Flogger - Mission 1.1 on the Ace difficulty setting. MiG-29 Fulcrum V2 - Mission 2.3 on the Rookie difficulty setting. MiG-31 Foxhound V1 - Mission 1.3 on the Ace difficulty setting. MiG-31 Foxhound V2 - Mission 2.1 on the Ace difficulty setting. T-45 GOSHAWK - Mission 1.1 on the Rookie difficulty setting. Yak-141 Freestyle - Mission 1.2 on the Ace difficulty setting.
Complete the Ace bonus objective in the final mission to unlock the SR-71 Blackbird's fourth weapon pack. This weapon pack includes the game's super weapon, the A-SLAMR. The A-SLAMR does not recharge after it is fired. Note: To unlock the SR-71 Blackbird plane and "The Big One" weapon pack at the same time under the Ace difficulty setting, complete both of the required bonus objectives.