What happened
On 30 January 2007, a Mooney M20C, registration ZS-FHM, was conducting a local flight departing from Tzaneen Aerodrome. The flight, which included the pilot and one passenger, lasted approximately forty minutes before the aircraft returned to the aerodrome to perform a series of touch-and-go landings on Runway 06. Following the initial touch-and-go, the pilot attempted a second maneuver. During this second approach, the aircraft touched down with the landing gear still in the retracted position, resulting in a wheels-up landing. There were 0 fatalities and 0 injuries during the incident.
The investigation
Investigators examined the cockpit environment and the pilot's actions leading up to the touchdown. The pilot reported that during the downwind leg of the approach, a serious conversation between the occupants distracted him, causing him to omit the vital action of lowering the landing gear. While the pilot noted that the approach speed was slightly higher than usual, he did not consider this a critical issue before touchdown.
Regarding cockpit instrumentation, the pilot noted that the landing gear indication lights, located on the upper left of the instrument panel, were excessively bright during daylight operations. To mitigate this, he had reduced the light intensity to 50%.
Furthermore, the investigation looked into the aircraft's automated safety systems. The Mooney M20C is equipped with an audio warning device that triggers when manifold pressure drops below 10 inches. The pilot reported that because he maintained a long, flat approach with power settings above this threshold, the warning did not activate. The pilot also noted a difference in safety margins compared to other aircraft types he has operated, such as Pipers, where the warning activates at a higher power setting of 14 inches.
Findings
- The primary cause of the incident was the pilot's failure to extend the landing gear due to distraction during a conversation in the cockpit.
- The pilot's use of a long, flat approach prevented the activation of the manufacturer's gear-unsafe audio warning, as the manifold pressure remained above the 10-inch threshold.
- The pilot had intentionally reduced the brightness of the landing gear indicator lights, which may have impacted the visibility of the gear status.