A full safety audit of the civilian maintenance contractor employed on the Royal Air Force's Queen's Flight began on 24 November, the UK Ministry of Defence (MoD) has confirmed. The check followed an investigator's interim report on a potentially catastrophic multiple-engine failure on a British Aerospace 146-100 C.Mk 1 on 6 November.
The investigations are focusing on the alleged failure by engineers to replace O-ring oil seals in the engine mag-plugs (magnetic chip-detectors) which led to rapid multiple oil-leaks. Maintenance at the aircraft's RAF Northolt base is sub-contracted to civilian joint-venture company FRA Serco. The MoD says that it expects to complete the audit by the end of December. FRA Serco declines to comment.
The 146 crew was forced to make an emergency landing after losing almost all engine power during a training flight over southern England. Operated by No 32 (The Royal) Squadron, based at RAF Northolt, the aircraft is tasked with flying the UK Royal family and senior politicians.
According to the MoD, the 146 had been airborne from Northolt for 15min when the crew noticed "fluctuations in all the engine oil quantity indicators", followed almost immediately by a low oil-pressure warning for the No 3 engine, which was shut down. The crew began an emergency diversion to London Stansted Airport.
During the approach, the crew reduced No 2 and No 4 engine thrust to flight-idle because they showed intermittent oil-pressure warnings. On finals, the No 2 engine was shut down, followed by No 4 on the runway, to protect the AlliedSignal ALF502R-5 turbofans from further damage.
Source: Flight International