Is it possible to destroy the helicopter too quick with the stinger? I just did a run and I shot the helicopter twice with the stinger. The helicopter was in a indefinite loop of spinning as it was suppose to crash, but it never did. Does anyone know what causes this?

Make sure you kill everyone before shooting it down with the stinger. If someone's in last stand, the heli won't go down.

oh damn, I didn't know about that. Thanks!