All campaign missions and planes
At the main menu, hold L + R and quickly press X, White, Black, Y(2), Black, White, X to unlock all campaign missions and planes.

Invincibility
Pause the game, then hold L and quickly press X, Y(2), X. Then, hold R and quickly press Y, X(2), Y. Repeat the code to disable its effect.

Increased damage by weapons
Pause the game, then hold L and quickly press White(2), Black. Then, hold R and quickly press Black(2), White. Repeat the code to disable its effect.