What happened
On 3 July 1998, a Cessna 310L, registration G-AZUY, was performing a private flight from Barton to Liverpool when the aircraft experienced a landing gear malfunction. During the final approach to Liverpool Airport, the pilot was momentarily distracted by a passenger's concern regarding nearby trees. While performing landing checks, the pilot noticed the nose gear indicator light was not green.
Upon noticing the indication, the pilot initiated a go-around and selected the landing gear up. During this maneuver, the aircraft's right mainwheel made contact with the runway in a lower-than-normal attitude, causing the right propeller to strike the ground. The pilot immediately reselected the landing gear down, shut down the engines, and brought the aircraft to a halt. The aircraft slid on its belly before stopping, and all three occupants evacuated without injury. The aircraft sustained damage and was considered beyond economic repair.
The investigation
Investigators examined the aircraft's landing gear actuation system, which uses a single electric motor and gearbox to move all three gears simultaneously. They found that the main gears had partially retracted while the aircraft was on the runway, while the nose gear remained in a retracted position.
Upon further inspection, it was discovered that the nose gear's adjusting bellcrank and fork bolt had suffered a single fast fracture. This failure prevented the motor's movement from reaching the nose gear and created a jamming condition that stopped the main gears from completing their extension cycle. Additionally, investigators found that the filament for the 'Gear Unsafe/In-transit' light was unserviceable, a fact known to the pilot prior to the flight.
Findings
- The primary cause of the gear malfunction was the fracture of the nose gear actuating linkage components.
- The pilot's decision to initiate a go-around after noticing the gear indication was a contributing factor to the main gear's movement during touchdown.
- A distraction caused by a passenger during the final approach prevented the pilot from identifying the gear configuration earlier.
- The landing gear configuration warning horn failed to sound until the throttles were fully closed.
- The unserviceable 'Gear Unsafe' light filament prevented the pilot from receiving a visual warning regarding the gear status.