What happened
On 7 May 2008, a Rans S6-116 Coyote II, registration G-BUTM, was conducting a training flight near Gamston, Nottingham. The flight was intended to familiarise the aircraft's owner with tailwheel operations, with an instructor on board to supervise. Several previous sorties had been completed that day, including various approaches and go-arounds.
During the accident flight, the aircraft approached the private Grove Farm airstrip in a light easterly wind. As the student pilot flared for landing on Runway 09, the flare was performed too high, resulting in a very heavy touchdown. Upon impact, the left main landing gear strut fractured. This caused the left wing to drop and the aircraft to veer left, eventually coming to rest upright in a crop field. The two crew members evacuated the aircraft safely after the engine and fuel were shut down. There were no injuries.
The investigation
Investigators examined the aircraft and the broken landing gear component. The left main landing gear strut, a steel rod tapering from a hollow section to a solid end, was sent for metallurgical analysis. The examination revealed that the strut had failed at the transition point between the tubular and solid sections.
Evidence of a pre-existing fatigue crack was discovered on the interior of the tubular section, though the crack depth was less than one millimetre and was not deemed to have significantly compromised the strut's ultimate strength. The strut also showed visible bending distortion near the wheel end. Furthermore, the investigation identified that the landing gear struts were 'rattling' within their fuselage sockets. While attempts had been made to shim these fittings, they still required further adjustment to achieve a proper fit. It was noted that the struts had previously been a tight fit when the aircraft was originally built.
Findings
- The primary cause of the accident was a heavy landing resulting from an improper flare.
- The left main landing gear strut failed due to a combination of the landing impact and a pre-existing fatigue crack.
- The landing gear struts were found to be loose within the fuselage fittings, requiring shims to maintain a proper fit.