While practicing auto-rotations during a military night training exercise, a Huey Cobra messes up and lands on its tail rotor. The landing is so hard it breaks off the tail boom. However, the chopper fortunately remains upright on its skids, sliding down the runway, doing 360s. As the Cobra slides past the tower, trailing a brilliant shower of sparks, this radio exchange takes place: Tower: Sir, do you need any assistance? Cobra: I dont know, Tower, we aint done crashin yet.