Accident Overview
A pilot departing from Miles City Airport in Montana experienced a catastrophic structural failure shortly after takeoff. The flight was conducted at night over an unlighted area. Air traffic control had cleared the pilot to climb to 6,000 feet. However, while the aircraft was at a relatively low altitude and high speed, the left wing outboard section failed and separated from the airframe. Following the detachment, the airplane became uncontrollable and entered a dive, impacting the ground in a field. The pilot, who was the only person on board, was killed in the crash.
Investigation Findings
The official investigation determined the probable cause of the accident to be an airframe failure in flight and an uncontrolled descent, which occurred after the pilot diverted attention from the operation of the aircraft. Contributing factors reported in the findings include: exceeding the designed stress limits of the aircraft, a failure related to the airframe wings, in-flight separation, overload failure, and a fire that occurred after impact.