Cheat List
At the New Game/Load Game menu, hold L + R + Z then press LEFT, UP, DOWN, A, RIGHT, B, START to drop a name entry/code entry screen. Input the following codes for the desired effect (effects are saved when you save your game). Note these are the same codes on the PS2 and Xbox versions.

Invincibility: SUPERMECH
Unlock all planes: WHERESMAX
Unlock levels: WEWILLWIN
Unlock multiplay stages: MULTIMAYHEM
Gun cools fast: SPACEFOLD
Missiles reloaded fast: MARSBASE
Both weapons reload fast: MIRIYA
One shot kills with gun: BACKSTABBER
One shot kills sniper mode: SNIPER
Unlock all paint skins: MISSMACROSS
Upside down view: FLIPSIDE
Clear all effects: CLEAR

Awards and Bonuses
Meritorious Service (Clear Force of Arms) Unlocks Izzy Paint Scheme
Distinguished Service (Clear Enemy Within) Unlocks Rick Paint Scheme
Master Airman (Kill 100 Fighter Pods)
R.D.F. Flying Ace (Complete Master Airman Set) Unlocks Debris Field Versus Map and Max Paint Scheme
R.D.F. Starburst (Clear All Boss Missions Twice) Unlocks Flood City Versus Map
Titanium Medal of Valor (Clear Knife's Edge) Unlocks VF-1J in Story and Versus Mode
Bronze Cross (Kill 50 Battle Pods)
Silver Cross (Kill 75 Battle Pods and Complete Bronze Cross Set)
Gold Cross (Kill 100 Battle Pods and Complete Silver Cross Set)
Southern Cross (Complete Gold Cross Set) Unlocks Factory Versus Map and Armoured Valkerie in Versus Mode
Silver Shield (Clear Graveyard using VF-1A) Unlocks Graveyard Versus Map and Miriya Paint Scheme
Superior Defence (Clear Attrition) Unlocks Graystone Versus Map
Gold Nova (Clear Vengeance 3 times)
R.D.F. Supernova (Complete Gold Nova Set) Unlocks City in Space Versus Map and Patriot Paint Scheme
Robotech Marksman (Kill 50 Nousjadel-Ger in Sniper Mode) Unlocks Stealth Paint Scheme
Wolf Leader (Clear To the Death) Unlocks Wolf Paint Scheme and VF-1R in Story and Versus Mode
Tuna Head (Kill 50 Del Regults) Unlocks Queadluun-Rau for Versus Mode
Jolly Roger (Clear Party Crashers 3 times) Unlocks Skull Leader Paint Scheme
Unlocking Chapter 4 unlocks the VF-1S
Unlocking Chapter 5 unlocks FAST Packs (Super Veritechs) for Story and Versus Modes