What happened
On the evening of the accident, an aircraft operating as Tanker 69 was conducting a corporate transport mission for Butler employees. The flight originated in Redmond, where approximately 1,600 gallons of fuel were loaded alongside eight passengers. After departing Redmond at roughly 19:45, the aircraft arrived at Klamath Falls at 20:29 to pick up two additional passengers.
The aircraft departed Klamath Falls runway 14 at 20:40, heading toward a final destination in Medford. During the flight, observers noted the plane performing a sharp right turn approximately one mile south of the airport runway. Shortly after, a pilot flying nearby observed the aircraft passing overhead at an estimated altitude of 750 feet above ground level, noting that the engine sounds seemed normal and the lights were active.
At approximately 20:47, witnesses near Surveyor Peak reported hearing unusual, rhythmic engine noises similar to a helicopter. This was followed by the sight of a fireball on the mountain peak. Personnel from the Weyerhauser Company and Oregon State Forestry Department, who were in the vicinity, also observed the explosion. The aircraft crashed at night at an elevation of approximately 6,400 feet, resulting in the total destruction of the airframe and 12 fatalities.
Findings
The investigation determined that the flight crew chose to execute a direct, high-speed flight profile at a low altitude. It is believed that the crew's familiarity with the local geography may have contributed to their decision to fly at such a low altitude.