What happened
On 21 May 2010, a private flight departing from Krugersdorp Aerodrome ended in a runway excursion at Grand Central Aerodrome. While performing the landing on Runway 17, the landing gear of the Cessna 210-L, registration ZS-PNG, collapsed upon touchdown. The impact caused the propeller to strike the runway surface, resulting in the aircraft skidding approximately 192 metres before coming to a halt at the edge of the runway. The pilot, who was uninjured, was able to disembark the aircraft without assistance. The incident resulted in no fatalities and no injuries, though the aircraft sustained damage to the lower fuselage and the propeller.
The investigation
Investigators examined the flight sequence and the mechanical state of the aircraft following the incident. While the pilot believed the landing gear had been lowered during the downwind leg and noted a green down-locked light, the investigation established that the gear had actually remained retracted throughout the approach and landing. Post-incident testing by an approved maintenance organization found that the landing gear retraction and extension system was mechanically sound and that the hydraulic system was undamaged. However, the investigation identified a critical defect in the landing gear warning system: a microswitch wire had become detached from the switch, which prevented the unsafe gear warning horn from activating during the approach.
Findings
- The primary cause of the incident was the failure to extend the landing gear prior to landing.
- The landing gear warning system was non-functional because a microswitch wire had separated from the switch.
- The aircraft was properly maintained, having flown only 3.7 hours since its last mandatory periodic inspection.
- The pilot held a valid private pilot license and medical certificate at the time of the event.