What happened
A witness observed the aircraft taxiing to an active 5000-foot runway and departing without performing an engine run-up. During the takeoff roll, witnesses described the roll as long, noting that the airplane remained approximately 10 to 15 feet above the runway surface as it approached the end of the runway.
As the aircraft reached the departure end of the runway, it suddenly pitched up at a steep angle, reaching an altitude of approximately 300 to 400 feet. The aircraft then slowed and experienced a stall, rotating about 175 degrees on its vertical axis to the left. During this rotation, the nose briefly pitched up again before the airplane entered a near-vertical dive to the left. The aircraft disappeared behind a treeline, followed by two loud bangs and the sight of a fireball and black smoke.
The investigation
Post-accident examination of the wreckage revealed that the flap jack screw was in the up position. According to the pilot operating handbook, the normal procedure for takeoff requires flaps to be extended to 50 percent. While the takeoff ground distance based on performance data is 1776 feet, no anomalies were noted regarding the airframe, flight controls, or engine assembly during the examination.