What happened
On 24 April 2008, a Cessna F177RG aircraft, registration G-BFPZ, was conducting a private flight from Yeovil to Swansea Airport. During the approach to Runway 22, the pilot performed standard configuration changes, including the deployment of flaps. While the initial touchdown appeared normal, the aircraft's main landing gear retracted as it settled on the runway. This caused the aircraft to veer toward the Alpha taxiway intersection, where it came to a stop after scraping the runway surface for approximately 156 metres. There were no fatalities and no injuries to the pilot or the two passengers on board.
The investigation
The AAIB conducted an in-situ examination of the aircraft and the landing gear downlocks. The investigation noted that the pilot had experienced a similar incident earlier that same day, where the gear had failed to lock initially. During the accident sequence, the pilot noted that the gear horn sounded as the airspeed dropped through 100 knots, and the amber 'gear unsafe' light had illuminated and then extinguished during the gear extension process.
Following the aircraft's recovery, the owner activated the master switch, which triggered the completion of the gear deployment cycle and the illumination of the green 'gear down' light. An examination of the hydraulic downlock assemblies, which were the electro-mechanical type, showed no visible evidence of mechanical failure or defects. However, a full functional test could not be performed at the site due to the absence of jacking equipment.
Findings
- The pilot failed to visually confirm the green 'gear down' light was illuminated during the approach.
- The pilot relied on a verbal confirmation from the passenger regarding the gear status rather than verifying the cockpit indicators.
- The pilot omitted to check the landing gear downlock indication while occupied with other approach checklists.
- The main landing gear assemblies appeared to be in a normal, fully engaged state during the in-situ inspection.