GUY NORRIS / MOJAVE
Powerful engine could suit Emirates' need for 300ER performance boost
General Electric says on-going flight tests of the 115,000lb-thrust (512kN) GE90-115B for Boeing's ultra-long-range 777 derivatives prove the engine is fundamentally capable of further growth to 120,000lb and possibly beyond.
Emirates is in talks with Boeing about a -300ER order and could be a first customer for the higher-thrust engine as it seeks to boost performance of the twinjet in critical conditions from its Dubai hub (Flight International, 22-28 October). GE, which has amassed more than 60h of flight tests on the -115B, says it has "clearly demonstrated that the fan and core flow is adequate".
GE confirms that "technology developments are under way" to support a growth step which would ensure 120,000lb-thrust performance with adequate cost and operational margins. These include a new high-temperature disc alloy, in development for the Airbus A380's GE-Pratt & Whitney GP7200 engine, a new high-pressure (HP) turbine alloy and thermal barrier coating material for possible application in the low and HP turbines, static structure and other areas that are yet to be determined.
"From a technology standpoint, we have to be assured before we can begin any design activity," says GE90 advanced product integration manager Dick Ostrom.
The -115B is proving to be the "best test engine" to date, says GE flight test director Al Krejmas, who adds: "The new fan design has a lot better low-speed performance characteristics because it doesn't block the core and has probably around 5% more flow."
Preparations are also under way for critical 3.6kg (8lb) bird strike and blade-off tests in November. Tests of a 2.5kg birdstrike were completed on 8 October. Although a blade sustained damage which delaminated a section around 150mm (6in) from the tip, it "did not have material loss". The engine successfully performed the full profile needed for certification, says Ostrom.
Source: Flight International
