What happened
The pilot was positioned on the runway, waiting for another aircraft to clear the surface. As he prepared to begin his takeoff roll, he initiated a turn toward the downfield side of the airfield. During this maneuver, he intended to retard the throttle to manage power settings but instead advanced it, increasing engine power. The aircraft accelerated and crossed the runway at an angle, becoming airborne prematurely. While climbing, the aircraft collided with a tree.
The investigation
The pilot is a paraplegic who operates the aircraft using a hand-controlled rudder bar in conjunction with a conventional throttle. The investigation focused on the control inputs made during the critical phase of takeoff. The sequence of events indicated that the pilot's physical adaptation for steering did not prevent the error in power management.
Findings
The primary factor contributing to the accident was the misapplication of the throttle. The pilot advanced the throttle when he should have retarded it, leading to an uncommanded increase in power during a low-altitude turn. This resulted in the aircraft becoming airborne before reaching the intended takeoff speed or configuration, causing it to strike a tree. The pilot's physical disability required specialized controls, but the error was related to the specific control input rather than the equipment itself.
Safety message
Pilots with physical disabilities who utilize adapted control systems must ensure that their muscle memory and operational procedures for power management remain distinct from steering inputs, particularly during high-workload phases like takeoff. Regular review of control sequences is essential to prevent misapplication of throttle or other critical controls.