The collapse of a main landing gear set on a British Airways Avro RJ in February 2009 was set up by improper maintenance at a U.S. repair station three years before--work that later became the subject of an emergency AD.
The incident occurred on February 13, 2009, when the Avro RJ 100 touched down at London City Airport after what investigators said was an "uneventful flight," according to an AAIB report
. A detailed investigation revealed three fatigue cracks in the main gear fitting as the cause of the failure. Investigators determined that the cracks were caused by improper work carried out at Sterling, Va.'s Messier Services during a January 2006 overhaul. The work was specified in a Messier-Dowty service bulletin, which was a terminating action for a series of inspections and repairs. Explained AAIB:
The nose landing gear main fitting failed following the formation of multiple fatigue cracks within the upper section of the inner bore, originating at the base of machining grooves in the bore surface. These had formed because the improved surface finish, introduced by SB [Service Bulletin] 146-32-150, had not been properly embodied at previous overhaul by Messier services Inc, despite their overhaul records showing its incorporation. The operator had been in full compliance with the service Bulletin relating to regular inspection of the main fitting, and embodiment of SB 146-32-150 at overhaul removed the requirement for these inspections by the operator.
Two weeks after the incident, BAE Systems issued an alert service bulletin re-introducing repetitive inspections on gear sets that had the terminating bulletin accomplished. Later last year, new sets of instructions were released in bulletins by both BAE Systems and gear supplier Messier Dowty, leading to an EASA emergency AD
All 67 passengers and five crewmembers escaped the February 2009 incident relatively unscathed--the AAIB report lists two minor injuries. The aircraft is another story. From the report:
Following a normal touchdown, the fracture of the nose landing gear main fitting allowed the nose gear to collapse rearwards and penetrate the lower fuselage, causing significant damage to the equipment bay and the battery to become disconnected. The penetration of the fuselage allowed smoke and fumes produced by the consequent release of hydraulic fluid to enter the cockpit and passenger cabin. With the battery disconnected and after the engines were shut down, all power to the aircraft PA systems was lost and the remote cockpit door release mechanism became inoperative.
Access the full report in .PDF form here
No word yet on when British Parliament will convene hearings on the dangers of domestic carriers outsourcing work to foreign repair stations....