History of Flight
On 16 October 2019, an instructor and a student pilot departed Rand Aerodrome (FAGM) at approximately 1333Z on a training flight aboard a Cessna 172P aircraft with registration ZS-OBD. The aircraft was carrying 26 US gallons of Jet A1 (diesel) fuel. The flight proceeded to the general flying area where the instructor demonstrated straight and level flight exercises. After about 30 minutes, the student pilot, who was the pilot flying, set engine power to 62% for cruise on the return leg. At approximately 1402Z, while cruising at 7000 feet above mean sea level about 5 nautical miles east of the Grasmere VOR, the engine stopped. The instructor took control and attempted to restart the engine using the backup FADEC system, but was unsuccessful. He then elected to perform a forced landing on an open field at the Kalbasfontein farm. The aircraft touched down safely at 1406Z; both occupants were not injured. The aircraft sustained no damage in the incident.
Investigation Findings
The investigation determined that the engine stoppage was caused by a failure of the timing chain, which resulted in valve timing being out of synchronization and valves contacting the pistons. Contributing factors included the timing chain having been incorrectly fitted and incorrect alignment of the camshaft gears. The aircraft was not damaged, and no other damage occurred.
Personnel Information
The instructor held a valid Commercial Pilot Licence with 1780.9 total flying hours, including 71.4 hours on the Cessna 172P. The student pilot, aged 15, had 9.5 total flying hours and did not hold a student pilot licence or medical certificate at the time. The investigation noted that the aviation training organization contravened regulations regarding student pilot licence requirements.