What happened
On 30 August 2003, an Aeronca 11AC Chief, registration G-IVOR, was being prepared for flight at Bodmin Airfield, Cornwall. Following the completion of pre-start checks and the standard priming of the engine, the pilot's passenger attempted to start the engine by hand swinging the propeller. During the second swing, the engine experienced a kickback. As the engine coughed, the metal trailing edge of a propeller blade struck the passenger's right hand, specifically between the wrist and the base of the little finger. The impact resulted in a broken bone and a severe laceration. The pilot immediately deactivated the non-impulse magnetos and provided first aid.
The investigation
The investigation established that the individual swinging the propeller was not anticipating the engine to fire at that moment. This lack of expectation was influenced by a previous attempt on a different day, where the same individual had spent nearly two hours attempting to start the engine without success. Because the aircraft was fitted with non-impulse magnetos, a more vigorous swing is required to initiate the start compared to impulse-type systems. The investigation also noted a recurring pattern of such incidents, noting that this was the fifth instance of injury involving a propeller hand-swing starter reported since February 2000, with the person being caught off guard in three of those cases.