What happened
The incident occurred during pre-flight preparations when the pilot instructed the passenger on how to hold the brakes. The pilot then exited the aircraft to start the engine by hand-propping. Once the engine started, the passenger was unable to maintain control of the aircraft. The aircraft began to taxi unintentionally and collided with a parked automobile before the pilot could re-enter the cabin and apply the brakes.
The investigation
The investigation focused on the sequence of events surrounding the engine start procedure. It was determined that the passenger, despite receiving instructions, lacked the ability to manage the aircraft's movement effectively during the critical phase of engine ignition. The mechanical systems of the aircraft were not found to be at fault; rather, the issue stemmed from human factors and procedural execution.
Findings
The primary factor contributing to this incident was the loss of directional control by the passenger during the hand-prop start. This highlights the risks associated with allowing non-pilots to manage aircraft braking systems without direct supervision or adequate experience. The pilot's decision to exit the aircraft left the controls in the hands of an individual who could not react appropriately to the engine's power application.
Safety message
Pilots should ensure that any person assisting with engine starts is fully competent and capable of controlling the aircraft. It is critical to maintain direct supervision or use alternative starting methods when passengers are involved in pre-flight procedures to prevent uncontrolled movement.