What happened
On 31 January 2006, a Fournier RF4D, registration G-AVKD, was conducting a private local flight near Lasham Airfield, Hampshire. During the flight, the pilot discovered that a map had become trapped beneath the aircraft's landing gear Raise/Lower lever. In an attempt to free the map, the pilot released the landing gear lock and moved the lever forward. While the pilot successfully cleared the map, he failed to properly follow the sequence required to re-extend the gear.
During the downwind leg of the flight, the pilot believed the landing gear was in the down position. However, upon touchdown on the grass runway, it became apparent that the main wheel had retracted. The aircraft came to a stop with no injuries to the pilot, though the propeller was broken and the engine required testing for shock load.
The investigation
The AAIB examined the manual retraction mechanism of the single mainwheel. The system utilizes a lever on the right side of the cockpit; the lever is vertical when the gear is down and moves aft to retract it. A locking lever on the centre console is used to secure the gear in either the UP or DOWN position. The investigation established that the pilot's attempt to clear the map led to the gear being placed in an 'out-of-phase' state with the control lever. Specifically, the pilot believed he had lowered the gear, but his actions had actually resulted in the gear being retracted.
Findings
- The pilot's primary error was failing to verify the landing gear position after manipulating the controls to clear the trapped map.
- The pilot had recently returned to the aircraft syndicate after a multi-year absence.
- The landing gear control positions were not explicitly labelled, which may have contributed to the confusion during the sequence of operations.