Cheat Codes: Fly the friendlier skies.
Increased Firepower
Pause the game, hold L2 and then press L1, L1, R1, release L2, hold R2, then press R1, R1, L1
Invincibility
Pause the game, hold L2 and then press Square, Triangle, Triangle Square, release L2, hold R2, then press Triangle, Square, Square, Triangle
Unlock All Missions and Planes
At the Title Menu hold L2 and R2 and then press Square, L1, R1, Triangle, Triangle, R1, L1, Square