What happened
During the final approach of an uneventful flight, the pilot deployed the landing gear and wing flaps, noting that the cockpit indicators showed the gear was down and locked. However, upon touching the runway, the aircraft began to sink and produced unusual noises. Once the aircraft came to a halt on the right side of the runway, the pilot observed that the landing gear selector handle was in the up position. The pilot then moved the handle back to the down position before the crew exited the aircraft.
The aircraft, a unspecified aircraft type, sustained significant damage due to contact with the runway surface. Investigation of the wreckage revealed that all three landing gear assemblies were in a partially-extended state. The propeller assemblies were damaged by runway contact, and the pressure vessel was punctured by a propeller blade. Evidence from the runway, including skid marks, indicated a sequence of events that did not align with the pilot's initial report regarding the gear handle position.
Findings
Investigation of the landing gear components showed no signs of mechanical failure or pre-existing malfunctions. The gear handle mechanism, which utilizes an electrical switch requiring a specific pull-to-move action, showed no evidence of accidental movement. Because the gear is operated by an electric motor without a direct mechanical linkage to the handle, the physical evidence suggested the pilot likely attempted to extend the gear immediately before touchdown.
Several human factors were identified as contributing to the incident. The pilot reported significant sleep deprivation following multiple interruptions the previous night. Additionally, the pilot had completed seven flight legs totaling 5.2 hours on the day of the accident and had consumed very little food. It is concluded that pilot fatigue likely led to the failure to verify that the landing gear was fully extended and locked prior to landing.