At the title screen, enter the following codes to unlock the corresponding cheat. If you entered the cheats correctly, you'll hear a confirming sound.

Press Down, Down, Down, Down, Down, R, R.
Press Up, Down, Up, Down, L, R, L, R.
Press Up, Right, Down, Left, R, L, L, L.
Press Right, Right, Right, Up, Up, L, L.

Successfully complete the game as Max Sterling under the normal or advanced difficulty setting.
Successfully complete the game as Miriya S. under the normal or advanced difficulty setting.
Successfully complete the game as Ben Dixon under the normal or advanced difficulty setting.
Successfully complete the game as Rich Hunter under the normal or advanced difficulty setting.
Successfully complete the game as Roy Fokker under the normal or advanced difficulty setting.
Successfully complete the game with all five default characters under the normal or advanced difficulty setting.
Successfully complete the game with all five default and five secret pilots under the normal or advanced difficulty setting.