Cheat mode:
Log on with the name Viper to enable cheat mode. 
In addition to being able to select any mission, enter 
one of the following codes during game play to 
activate the corresponding cheat function.

Effect -Code
Invincibility [Alt] + I 
Full ammo[Alt] + L 
No damage[Alt] + R 
View all targets on radar [Alt] + A 
Crash Viper[Alt] + X 
Toggle real/arcade flight model [Alt] + Q 
No smoke trails [Alt] + K 
Display framerate [Alt] + J