What happened
On the morning of 13 February 2023, a Cessna U206C Super Skywagon, registration ZS-ZGZ, departed from Delta 200 Airfield (FADX) in the Western Cape for a scheduled sport parachuting flight. The aircraft was carrying a pilot and six passengers, including tandem instructors. After climbing to 4,500 feet within the Terminal Manoeuvring Area, the crew was alerted to a passenger feeling unwell, prompting a request to descend and return to the airfield.
During this descent, a loud bang was heard from the engine, followed by oil spraying across the windscreen. The pilot immediately executed engine failure procedures, shut down the engine, and broadcast a Mayday call. Utilizing the remaining glide capability, the pilot identified a nearby road and performed a successful forced landing approximately 2 nautical miles north of FADX. All occupants exited the aircraft without injury.
The investigation
SACAA AIID investigators examined the aircraft's maintenance history and performed a detailed teardown of the Continental IO-550-F27B engine. Records indicated the aircraft had undergone a 100-hour inspection approximately 44 flight hours prior to the incident. The engine had been in service on this airframe since 2015 and was well within its time-between-overhaul limits.
Post-incident inspection of the engine revealed a hole in the right side of the crankcase. This breach was caused by the No. 5 connecting rod, which had been displaced with enough force to eject fragments through the engine cowling. The investigation focused on the internal mechanics of the No. 5 cylinder assembly to identify the origin of the mechanical failure.