The OH-6 Cayuse was a Light Observation Helicopter, known as a "Loach," that saw extensive action during the Viet Nam War. In search operations it normally carried no attached armament, while the rear-seat gunner usually had an M-60 machine gun as well as smoke and WP grenades to mark target locations. Its greatest advantages were very fast speed and maneuverability, and the pilot would fly in a right turn at tree-top height at about 30 mph before, once the enemy was spotted, vectoring straight away from the target at maximum speed. A Cobra helicopter normally protected the Loach from 1500 feet and would attack once contact with the enemy was made, in a search and destroy mission. About 75% of air crews were killed or wounded, and most OH-6A helicopters were shot down and/or damaged, though many were recovered and repaired to fly again. Some OH-6A helicopters were armed with M75 40mm grenade launchers and the M27 "minigun."