What happened
On 18 March 2013, a Cessna T210J, registration ZS-FUW, was performing a test flight at Wonderboom National Airport (FAWB) following a maintenance inspection. During the landing approach, the pilot attempted to deploy the landing gear but discovered that the right-hand main gear failed to reach the locked position. Despite attempts to utilize the emergency extension system, the gear remained unsecured.
Upon touchdown on runway 29, the right-hand main landing gear collapsed. The aircraft veered slightly right of the centerline, causing the right-hand wing tip, elevator, and stabilizer to sustain damage. Although fuel leaked from the right-hand tank filler cap, airport rescue and fire fighting services arrived promptly to apply foam and prevent a fire. The pilot escaped the aircraft without injury.
The investigation
SACAA AIID investigators examined the aircraft's mechanical systems and maintenance history. Post-accident testing of the landing gear confirmed that the gear failed to lock in the down position during both normal and emergency extension cycles.
Upon dismantling the right-hand main landing gear actuator, investigators found that the ram had severed near its outer tip. Analysis of the fracture surface revealed clear evidence of metal fatigue. Further inspection of the left-hand main landing gear actuator revealed a crack in the same location, suggesting a potential systemic issue. The investigation also noted that while the maintenance manual requires the actuator casing to be inspected for cracks every 300 hours, there was no existing requirement to inspect the ram itself.