Base Invaders. Fly the plane on the landingstrip next to the middle lazer. if you´re with some other players; Kill the guards that come in the army truck. Snipe the three guards in the Hangar. Get the cargobob out. After this start bombing the lazers with another lazer or just sticky bomb them. One player can already fly back to the sandy shores airstrip.
The guards only starts spawning like crazy after one of the lazers gets destroyed. So make sure to get the cargobob first.