Collision Sequence
A flight of two military helicopters and a fixed-wing airplane, registration N8343D, were operating at the same altitude. The helicopters were on a northerly heading while the airplane was on a converging northwesterly heading. There were no indications that the occupants of either aircraft saw each other prior to the midair collision. The crew of the second helicopter observed the airplane approaching but did not have time to radio a warning. Following the collision, the airplane entered an uncontrolled descent. The helicopter pilot performed a precautionary run-on landing and executed an emergency shutdown.
Pilot Factors
The airplane pilot, who was 5 feet 2 inches tall, used a pillow placed on the seat bottom to increase seated height. The seat did not have a vertical adjustment feature. The airplane pilot was not communicating with air traffic control (ATC). The helicopter pilot was receiving flight following services but had not received any conflicting traffic advisories.
Environmental Conditions
The sun was positioned in the southwest quadrant at the time of the accident. Scattered clouds were present, and visibility was 20 miles. The top and bottom rotating beacons, as well as the landing lights of both helicopters, were illuminated.
Air Traffic Control
The airplane's transponder was squawking code 1200, but its altitude returns were reported as erratic and unreliable. This unreliability disabled the automatic intruder program. The controller did not see the airplane as a primary target because he was busy handling other traffic.