BOEING RESUMED extended-range twin-engined operations (ETOPS) testing of the Rolls-Royce Trent 800-powered 777 on 11 July, after foreign-object damage was determined to be the cause of a surge which halted testing on 16 June (Flight International, 3-9 July). Testing for 180min ETOPS clearance is expected to be completed on schedule at the end of July, the engine manufacturer says.
The 1,000-cycle ETOPS flight-test programme was put on hold while the affected engine was removed and replaced with another "aged" Trent. The nature of the object which caused the damage to the high-pressure compressor has not yet been revealed.
The replacement engine has undergone 2,000 cycles of ground testing and another 500 flight-test cycles, says R-R, and will be used for the remainder of ETOPS testing. Flying was halted after 886 cycles had been completed.
General Electric has received US certification for the 410kN (92,000lb)-thrust GE90-92B growth engine for the 777. Flight-testing on the 777-200 Increased Gross Weight (IGW) variant is to begin in September. The engine will enter service with British Airways in early 1997.
Source: Flight International
