What happened
On 9 January 2003, a Rans S6-116 Coyote II, registration G-BUWK, was conducting a private flight from a farm strip in Sussex to Lydd Airport, Kent. The weather conditions were cold but clear. After an uneventful landing on Runway 04, the aircraft vacated the runway and began taxiing on a northwesterly heading toward the parking apron.
As the aircraft moved toward Hold C, the right wing began to lift. Despite the pilot applying into-wind aileron to counteract the movement, the aircraft rose into the air. It briefly balanced on its nosewheel and left main wheel before tipping forward onto its nose, coming to rest in an inverted position. The pilot, who was wearing a flying helmet and secured by a lap strap and diagonal shoulder harness, struck his head against the cabin roof but was able to exit the aircraft through the left door without injury.
The investigation
Investigators examined the circumstances of the taxiing accident and the environmental conditions at the time. The Aerodrome Flight Information Service (AFIS) reported winds of 050/23 kt, which were stronger than the 050/17 kt winds reported during the landing phase.
Analysis of the aircraft's configuration noted that the aircraft was carrying a low weight of fuel and had no passenger in the right seat. The investigation also considered the surface conditions, noting that while the aircraft often slides on grass during crosswind taxiing, the friction of the tarmac surface at Lydd Airport may have contributed to the tipping motion.
Findings
- The aircraft tipped due to a gust of wind acting on the horizontal stabiliser and the underside of the fuselage after the right wheel had lifted.
- The light weight of the aircraft, caused by low fuel levels and the absence of a passenger, increased susceptibility to wind effects.
- The high friction of the tarmac surface likely prevented the aircraft from sliding, instead facilitating the tipping motion.
- The pilot's head contact with the cabin roof was likely mitigated by the use of a flying helmet, though a tighter lap strap might have prevented the impact.