What happened
On 13 August 2006, a Beechcraft BE58 Baron, registration G-BTFT, was conducting a private multi-leg flight involving stops at Thruxton, Bristol Filton, Kilrush, and Deauville. During the final leg of the day, the aircraft approached Denham Aerodrome as a line of thunderstorms moved in from the north-east.
After an initial go-around due to excessive approach speed, the pilot attempted a second landing. As the aircraft crossed the runway threshold, the pilot noted a sensation of floating. The aircraft touched down further down the runway than intended. Upon application of the brakes, the aircraft began to slide, exiting the left side of the runway and skidding through a hedge at the aerodrome boundary. The aircraft eventually came to rest on a public road. There were no injuries to the pilot or the five passengers on board, though the aircraft sustained significant damage to both propellers, the right main landing gear, the right wing, the aileron, and the elevator.
The investigation
The investigation examined the aircraft's performance requirements and the runway conditions at the time of the accident. Witnesses at the scene reported seeing standing water on much of the runway. The investigation also reviewed the landing distance calculations for the aircraft's weight. At a landing weight of 2,383 kg, the manual indicates a dry tarmac ground roll of approximately 425 m.
Investigators noted that safety guidelines recommend increasing the landing distance required (LDR) by 15% for wet, paved runways, and further applying a factor of 1.43 to ensure the required distance does not exceed 70% of the available runway. The investigation found that the touchdown occurred with only approximately 470 m of runway remaining, which was insufficient for the required stopping distance.
Findings
- The aircraft experienced insufficient runway remaining beyond the touchdown point to allow for a safe stop under the prevailing conditions.
- Heavy rain and standing water on the runway likely contributed to the loss of directional control or caused the aircraft to aquaplane.
- The aircraft's touchdown point was further down the runway than planned, reducing the available distance for the ground roll.