The object of the game is to destroy as many helicopters and paratroopers as possible. If a paratrooper lands on the ground he may still be hit by flying debris, another paratrooper free- falling on top of him or by your gravity-bound shells.
There are three levels of play: Easy, Hard, and Insane. You may select the level of play before the game starts.
The game also keeps track of your statistics, how many shots fired, how many hits, how many choppers and troops hit, etc.
Keep in mind that you have until the START of the next sortie to try and kill the troops on the ground, using the gravity-bound shells or dropping burning wreckage on them. When the next sortie starts, if there are more than four (4) troops landed on either side of your base the game will end and your gun emplacement will be BLOWN UP!