What happened
On the morning of 14 October 2023, a Jodel F12A aircraft, registered ZS-UJM, was participating in a series of aerial fly-passes at Springs Aerodrome (FASI) in Gauteng. The flight was part of a scheduled event for the Central East Rand Photographic Society congress. While performing a pass over Runway 1-4 into the wind, the aircraft experienced a sudden and catastrophic structural failure. As the pilot initiated a pull-up maneuver, the wooden main wing spar failed, causing both wings to fold upward and detach from the fuselage. The loss of structural integrity caused the aircraft to roll and impact a grassy area adjacent to the runway. The impact resulted in two fatalities and the total destruction of the aircraft.
The investigation
SACAA AIID investigators examined the wreckage and the history of the aircraft to determine the cause of the mid-air breakup. The investigation focused on the integrity of the aircraft's wooden main spar and the maintenance history of the airframe. Investigators also reviewed the circumstances of previous incidents involving the same aircraft and pilot. Evidence was gathered from the wreckage, maintenance records, and even photographic sequences captured by attendees at the event which documented the wings folding vertically during the failure.
Findings
- The primary cause of the accident was a structural failure of the wooden main wing spar during flight.
- The integrity of the main spar had been previously compromised by the builder or repairer following a prior accident, which involved drilling several holes through the wooden spar beams.
- Maintenance of the main landing gear leaf springs showed evidence of poor workmanship, including the use of improper spacers and the bending of support plates.
- The aircraft's airworthiness was questionable due to a lack of traceability and poor record-keeping regarding repairs performed after a 2017 incident.
- The maintenance work on the landing gear was performed by individuals who were not aviation-qualified maintenance personnel.
Safety action
- It is recommended that the Director of Civil Aviation review the regulations and SA-CATS-24 regarding the requirements for rebuilding or repairing non-type certificated aircraft (NTCA) that have been destroyed in previous accidents.
- There is a need for clearer guidelines to ensure that aircraft rebuilt by individuals or organizations meet stringent safety and airworthiness standards.