What happened
The incident occurred during pre-flight operations when the pilot encountered a malfunction with the aircraft's electrical system. Specifically, the pilot discovered that the standard electric starter would not engage due to a battery failure. Rather than delaying the flight or seeking external assistance, he elected to manually hand start the engine.
A passenger, identified as the pilot's wife and a non-pilot, was seated in the cockpit during this procedure. As the engine began to turn over, the passenger attempted to manage the throttle lever to assist with the startup process. However, instead of closing or holding the throttle steady, she inadvertently opened it further. This sudden increase in engine power caused the aircraft to lurch forward unexpectedly.
The pilot was unable to re-enter the moving aircraft in time to regain control. The uncontrolled plane accelerated across the ramp and struck a nearby hangar. The impact caused the aircraft to spin around before finally coming to a complete stop.
The investigation
Investigation of the event focused on the sequence of events during the manual engine start. Investigators noted that the initial failure was mechanical, related to the battery's inability to crank the engine. The subsequent loss of control was attributed to human error during the critical phase of engine ignition. No evidence was found suggesting mechanical failure of the throttle linkage or fuel system prior to the startup attempt.
Findings
The primary factors contributing to this accident were the decision to perform a high-risk manual start and the lack of coordinated crew resource management during that procedure. The passenger's unfamiliarity with aircraft controls led to an unintended power increase at a moment when the aircraft was vulnerable to uncontrolled movement. Fuel control by the non-pilot was the immediate cause of the forward motion.
The accident highlights the dangers of hand starting engines in confined areas or near obstacles. It also underscores the necessity for clear communication and role definition between pilot and passenger during ground operations. One person was involved in the startup process who lacked the necessary training to handle engine controls safely.