British Airways has suspended extended-range twin-engine operations (ETOPS) flights using its three Boeing 777-200 increased-gross-weight aircraft after metal was found in the chip detectors of two engines. The problem was discovered during a routine inspection on 21 February, and three days later a Boston-bound 777-200IGWreturned to London after a cockpit chip-detector warning light came on. The engine was not shut down, but BA opted to suspend ETOPS flights in agreement with the UK Civil Aviation Authority.
GE says that the problem is caused by "bearing material coming loose" inside the GE90-92B's variable-speed/constant-frequency accessory gearbox, which is designed to handle higher loads than that of the existing 777-200. The gearbox drives a back-up electrical generator.
As an interim fix, the aircraft are being fitted with the shaft, gearbox and generator of the engine from the non-IGW -200. GE says it expects to deliver a redesigned gearbox bearing in "about a month". BA says it hopes to resume IGW ETOPS flights by 25 March.
BA says the affected aircraft will continue to be flown on non-ETOPS routes. The airline is initially having to inspect the engines after every flight of over 1.1h.
Source: Flight International
