What happened
On 29 October 2005, a training flight was being conducted at Rufforth Airfield, North Yorkshire, involving an instructor and a student pilot. The flight, intended to practice crosswind takeoff techniques, initially utilized Runway 24, which provided the necessary crosswind component. Following a successful takeoff, the crew performed several circuits using Runway 18.
During the first approach to Runway 18, the student pilot initially undershot the runway while using the airbrakes. The student corrected the approach angle by closing the airbrakes and then fully re-opened them as the aircraft neared the ground. This resulted in a firm landing. While the subsequent touch-and-go and following circuits were normal, a swing developed during the ground roll of the final landing. As the aircraft slowed and the wheel brakes were applied, the aircraft listed to the port side. The aircraft came to a stop immediately after the engine was shut down.
The investigation
Investigators examined the aircraft, a Hoffmann H 36 Dimona, registration G-KOKL, and found that the left main landing gear had collapsed rearwards. The investigation focused on the sequence of landings and the application of braking during the training session. The analysis considered whether the collapse was an isolated event or the result of cumulative structural fatigue.
Findings
- The left main landing gear collapsed under the force of positive braking during the final landing.
- The collapse was exacerbated by the firm landing and heavy braking performed during the training session.
- There was a possibility that the landing gear had sustained previous damage, potentially due to cumulative stress from repetitive, heavy application of the wheel brakes over a longer period.