What happened
On 10 June 2008, a modified Beech H35 Bonanza, registration G-ASJL, was performing a private flight at Compton Abbas Airfield in Dorset. Following a standard touchdown, the aircraft proceeded along the runway. Approximately halfway through the roll-out, the landing gear suddenly collapsed without prior warning. This caused the aircraft to slew toward the left side of the runway, eventually coming to a stop and obstructing the active surface. After the incident, the pilot shut down the fuel and electrical systems, and both the pilot and the single passenger exited the aircraft unharmed.
The investigation
The investigation focused on the mechanical failure of the landing gear during the ground phase of the flight. The aircraft was fitted with a weight-on-wheels microswitch designed to inhibit the retraction of the landing gear while the aircraft is in contact with the ground. Investigators examined whether this safety mechanism had been bypassed or failed. It was noted that the pilot may have accidentally moved the gear selector to the 'UP' position while intending to retract the flaps. Furthermore, the investigation considered the impact of the runway's surface, noting that the undulating nature of the terrain at Compton Abbas might have caused the microswitch to momentarily open, thereby permitting the gear to retract despite the aircraft being on the ground.
Findings
- The landing gear collapsed during the aircraft's roll-out on the runway.
- The landing gear selector may have been inadvertently moved to the UP position by the pilot.
- The runway surface was noted to be undulating, which could have triggered the weight-on-wheels microswitch to open.
- There were no injuries to the two occupants of the aircraft.