Fokker F27-500 Friendship, G-BVOB
After landing at Guernsey, the aircraft executed a 180? turn to the left in order to back-track the runway. After straightening up, the crew felt a violent shimmy/vibration from the left landing gear. Subsequent inspection revealed that the torque link centre bolt had failed, allowing the torque links to separate. This in turn had allowed the wheel assembly to castor about a vertical axis, resulting in damage to the tyres, wheel rims and brake components caused by the unsecured torque links. The head and shank of the failed bolt was found on the runway, together with a castellated nut and other debris. The separated, threaded tail of the bolt, onto which the nut had attached, was not found. The bolt had failed at the run-out of the threaded section, and it was concluded that the observed features on the fracture face were consistent with a tensile overload. Inside the nut, the threads had been severely damaged, consistent with an axial load having been applied in a direction away from the head of the bolt. It was not possible to establish the exact sequence of events that led to the bolt failure. Despite the extensive worldwide service experience of this aircraft type, the only similar occurrence the aircraft manufacturer was aware of involved a corrosion process. This had not happened in this case.
G-BVOB 10-05.pdf (280.08 kb)
Date of occurrence: 22 March 2005