Heatseeker Cheats

Successfully complete the Ace bonus objective for the final mission (Mission 4.5-Final Count Down) 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 once fired so use it wisely. Note: Both the SR-71 Blackbird plane and "The Big One" weapon pack can both be unlocked at the same time if playing under the Ace difficulty setting. Just complete both of the required bonus objectives to unlock the SR-71 and "The Big One" weapon pack together (instead of separately).

Successfully complete the Pilot bonus objective for the final mission (Mission 4.5-Final Count Down) to unlock this secret plane.

This guide can be use to unlock only from 1.1 Welcome to Paradise until 2.4 The Payback. Please note that the final stage is 4.5 the count down. All of those aircraft and weapon pack can only unlock by completing bonus objective (WP = Weapon Pack):

When you are told you need to land your plane, make sure you look for some blue rings floating around close to where you need to land. Slow your plane down (by using your airbrakes) and fly through the blue rings. This will deploy your landing gear and you will then be able to land your plane successfully.