On 25 November 1978, an Iroquois A2-770 helicopter took off from Yadnapinna destined for the base camp at El Alamein near Port Augusta in South Australia. On board were five military personnel. During the flight, the aircraft maintained a steady altitude of approximately 2200 feet, overflying the camp about 30 minutes later and gradually descending to 1700 feet. At 12.35am, the helicopter radioed its intention to commence descent.

The aircraft, two km from camp, struck a ridgeline at 791 feet. The helicopter exploded on impact. The A2-770 disintegrated spreading wreckage over a distance of 200 m and all onboard were killed.