What happened
On 18 October 2009, a Bantam B22J aircraft, registration ZU-DWN, was conducting a private flight from Ballito Microlight Airfield in KwaZulu-Natal. While flying at approximately 1000ft AMSL over the area south of Westbrook beach, the pilot experienced a sudden engine failure. Despite attempts to restart the engine, the pilot was forced to execute an emergency landing on the soft sand of the beach ahead.
The landing resulted in minor damage to the aircraft, specifically a bent nose wheel fork and slight damage to the nose cowling. The pilot, who was the sole occupant, sustained no injuries.
The investigation
SACAA AIID investigators examined the engine following the incident. A teardown of the Jabiru 2200 engine revealed that the failure was mechanical in nature. The investigation focused on the assembly of the engine flywheel and the pole plate.
Findings
Technical analysis established that one of the two screws securing the pole plate to the engine flywheel had sheared off, while the remaining screw was found to be loose and bent. As the engine was running, centrifugal force caused the pole plate to shift outward. This movement caused the plate to strike both ignition coils, resulting in physical damage and a total loss of the ignition spark required to maintain engine operation.
At the time of the incident, the pilot held a valid microlight license and medical certificate. The aircraft had been maintained by an approved person, and the weather conditions were clear with good visibility.