Chopper Attack

Alien Disrupter Weapon
Beat level 7 on the expert difficulty level.
Debug Mode
From the Title screen, when "Press Start" appears, hold Z and press Right, Left, Up, Down, A, B, Start.
Super Choppers
From the Main Menu, hold L + R + Z and press Start before selecting a chopper.
Level Select
From the Title screen, when "Press Start" appears, press the C-Up (x7) to activate the level select.
Presidential Bailout
During a game, press Z + C-Up + C-Down, then launch a homing cluster at your opponent. If it hits, you will see the president jump out of the plane.
Chopper Preview
On the chopper selection screen, highlight a chopper. Then, press L to display the statistics screen. Press the Analog-Stick to rotate the model of the chopper.

Various Cheats

Infinite Weapon First Position - 8012943b0063

Infinite Weapon Second Position - 8012943f0063

Infinite Weapon Third Position - 801294430063

Gun Four-Way Shot - 801297230004

Infinite Fuel - 81129726ffff

Infinite Armor - 811296c80045