What happened
The incident began while the pilot was preparing the aircraft for flight. The battery had discharged completely, necessitating a hand-propped engine start. Once the engine was running, the pilot reportedly left the aircraft unattended with the throttle set to idle speed. He stated that he was conducting a post-start inspection for oil leaks.
During this time, a bystander entered the cockpit and advanced the throttle sufficiently to move the aircraft. The plane accelerated off its parking spot, struck a fence, and fell into a ditch, resulting in a nose-over attitude. The bystander subsequently fled the scene.
The investigation
Investigation of the mechanical aspects focused on the engine start procedure and the unattended state of the aircraft. The battery was found to be dead, which led to the manual start method. No mechanical failure was cited as the primary cause; rather, the movement was attributed to human action while the engine was operational.
Findings
The critical factors in this accident were the decision to leave the aircraft unattended with the engine running and the unauthorized manipulation of the throttle by a third party. The lack of supervision allowed the bystander to access the cockpit controls. The resulting impact with the fence and ditch caused significant damage to the airframe.
Safety message
Pilots must never leave an aircraft unattended with the engine running, even for brief periods. This practice creates a severe hazard, as unauthorized individuals may inadvertently or intentionally manipulate flight controls, leading to loss of control and injury.