Both pilots were reportedly avid big horn sheep hunters. On the morning of the accident, the second pilot picked up topographical charts of the area where the aircraft crashed. It was an area where the Montana Department of Fish, Wildlife, and Parks (FWP) had recently relocated a herd of big horn sheep. The second pilot was also a recently retired FWP regional supervisor who had been in charge of sheep herd relocations. One witness saw the aircraft flying east across the mountains at low altitude. It suddenly dropped out of sight and smoke was seen coming from the area. Winds aloft were forecast to be out of the NNW at 14-15 knots. No evidence was found to indicate any pre-impact failure or malfunction. The aircraft struck the east wall of 7300 ft high Bund Gulch at about the 7250 ft level in a nose high, left wing low attitude. The carburetor throttle valve was full open. The propeller bore evidence of rotation at impact.