Falcons baby
Set the system date to May 15. Start the game and select any campaign and mission. Click on the "Ready to Fly" icon and carefully watch the loading screen.
Restore Ammo
Type in "revenge" while playing.
Invincibility
In a campaign, press 'CTRL+Z' followed by 'Z' (you should here a click) to become invincible. Don't forget to press the same keys again before you exit the game, otherwise your score will be very low.
