What happened
On 22 July 2006, a Piper PA-15, registration G-ALGA, was conducting a training flight at a farm strip located east of Fenland in Marshland, Suffolk. The weather conditions were favorable, characterized by good visibility and a light, slightly gusty north-westerly wind of approximately 5 knots.
During the approach to Runway 03, the pilot managed a standard landing, though the aircraft touched down slightly left of the runway centerline with the left wing slightly low due to a minor crosswind. Shortly after touchdown, the pilot heard a loud cracking sound. The left main landing gear failed at the shock strut end fitting, causing the gear to fold outward. As the aircraft continued along the grass surface, the propeller tips struck the ground and detached, and the left wing tip made contact with the earth. The aircraft slid a short distance before coming to a halt on its right main gear, tail wheel, and left wing tip. The pilot was able to exit the aircraft safely, and no injuries or fire were reported.
The investigation
Investigators examined the wreckage and the aircraft's maintenance records to determine the cause of the gear collapse. The inspection of the left main landing gear revealed that the shock strut end fitting had failed. Specifically, the fitting was being pulled from the strut, placing the component under a tensile load while the aircraft was on the ground.
Technical analysis showed that the hole for the securing bolt had become elongated in the direction of the load, eventually leading to a failure due to tensile overload. While the aircraft logbook did not specify when this particular component was installed, its physical condition suggested it had been in use for a significant period. The investigation also noted that the internal wear within the bolt hole was not visible while the fitting remained attached to the strut, and there is currently no regulatory requirement to disassemble this component for inspection.