What happened
On 16 November 2003, a Christen Eagle II, registration G-EEGL, was performing a private flight at Andrewsfield, Essex. The pilot executed a standard approach and landing on Runway 27. During the landing roll, as the aircraft reached a speed of approximately 50 mph, the landing gear collapsed. The pilot noted that the runway surface was rutted at the time of the incident. The aircraft sustained substantial damage to its propeller, landing gear, and the underside of the left lower wing, though there were no injuries to the two crew members on board.
The investigation
Investigators examined the aircraft's tubular steel structure and aluminium alloy panels, focusing specifically on the area where the spring beam is bolted to the fuselage cross bar. The examination, conducted alongside a repair agency, revealed that several tubes and their welded attachments to the cross bar had failed. This failure was caused by a vertical overload.
Further inspection of the left stub axle revealed that four 'nyloc' nuts had detached, which subsequently stripped the threads. The associated bolts had undergone deformation due to a combination of vertical and rearward loads. While the physical deformation confirmed an overload event, investigators also identified corrosion within the internal bores of the fractured tubes. This corrosion suggested that structural damage might have been accumulating over several previous landings.
Findings
- The primary cause of the gear collapse was the failure of the tubular steel structure and welded attachments due to vertical overload.
- The presence of corrosion on the fracture surfaces indicated that the structural integrity may have been compromised by damage occurring during previous operations.
- The bolts and nuts on the left stub axle failed due to a combination of vertical and rearward forces.
- No evidence of this specific structural damage had been identified during a permit renewal inspection conducted by the PFA in October 2003.