Several General Electric GE90-powered Boeing 777s were temporarily withdrawn from service earlier this month after borescope inspections revealed "light airfoil damage" in the compressor sections of five engines.
British Airways said last week that two of its four 777s had been grounded, and it was expecting replacement engines to be delivered by 2 February.
The damage was caused after "pieces of the compressor discharge pressure manifold came loose, went through the bleed [air] system, and damaged the compressor", says GE. The problem, which was discovered on 17 January, affected four GE90s belonging to British Airways, and one engine belonging to China Southern. All were taken off the wing for repairs.
GE says that a "ruggedised" manifold has been used on GE90s produced since late 1996, and that this will be retrofitted to earlier engines to eliminate the problem.
The GE90-powered Boeing 777-200 Increased Gross Weight has been certificated by the US Federal Aviation Administration. The airframe/engine combination is expected to receive 180min extended-range twin-engine operations approval "in the next few weeks", says GE. First delivery is scheduled for early this month, to British Airways.
Source: Flight International
