What happened
On 6 November 2012, a Cessna 210G was conducting a training flight at Aeropark Aerodrome, Gauteng, as part of a student's conversion exercises. The flight, operated under Part 141 training, involved a flight instructor and a student pilot. After successfully completing three touch-and-go circuits, the instructor initiated a fourth circuit at a low altitude to demonstrate a short-field landing technique.
During this maneuver, the instructor selected the landing gear to the down position. However, the crew failed to verify that the gear was fully extended and locked or to check for the green gear-down indication. Upon touchdown, the occupants realized the gear was not locked, resulting in a wheels-up landing. The aircraft skidded to the right of the active runway and came to a stop on a gravel surface. No injuries were reported.
The investigation
Investigators examined the aircraft following the incident and discovered a 55mm Teflon spacer lodged within the gear selector mechanism. This component was identified as part of the assembly used to secure the autopilot unit. The investigation established that this spacer had been left in the mechanism following recent maintenance work performed on the aircraft's autopilot system.