1. While the game is paused enter the following codes for the corresponding effect:

Maximum Fuel and Armor - press Select, L2, Select, R2, T, T, T, O
Maximum Weapons - press Select, L2, Select, R2, L1, L2, R1, R2
Cycle Through Gun Modes - press Select, L2, Select, R2, Select, Select, Select
Summon Wingman - press Select, L2, Select, R2, S, S, S, O
Mission Skip - press Select, L2, Select, R2, T, T, T, D, D, D
Upgrade Weapon - press Select, L2, Select, R2, L1, L1, R1, R1

Access to all levels:
Press and hold Left & L2 at the title screen then press Select. A sound will confirm correct ode entry. You can access levels at the 'insertion points' map.

Secret Deathmatch Mode:
Press and hold Select and R2 on both controllers at the main title screen.