Lethal Skies Cheats
Certain planes can be unlocked by simply finishing a mission, such as the X-16 Haggard which can be unlocked by blowing up the mansion and completing mission 6. Other planes can be unlocked by finishing missions and acheiving the S-Rank (F-22 Raptor in Mission 17) for that particular mission. Once a plane has been unlocked you can select any...
Using your machine gun to destroy ground targets is quite difficult, but when fighting other airborne gamers just need to shoot in a general vicinity of a plane to take it down. Thus making the machine gun very effective for short range dogfighting.
Unfortunately the game sometimes glitches and automatically picks a target which is blocked by a building and/or behind a building. The targeting system is helpful because it tells you exactly what to part of a target you need to destroy. But if you are solely left with the machine gun your targeting system will be mysteriously missing.