General Electric GE90

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GE90

NASA GE90 airflow simulation

GE90-115B fanblade, on display at New York's Museum of Modern Art.

General Electric GE90 is a family of high-bypass turbofan engines built by GE-Aviation for the Boeing 777, with thrust ranging from 74,000 to 115,000 lb_f (329 to 512 kN). It was first introduced in November 1995 on British Airways' 777s, and is only available on the 777. The engine is one of three options for the 777-200, -200ER, and -300, and the exclusive engine of the -200LR and -300ER.

The GE90 series are physically the largest engines in aviation history, the fan diameter of the original series being 123 in (312 cm). The latest variant, the GE90-115B, has a fan diameter of 128 in (325 cm). According to the Guinness Book of Records, at 127,900 lb_f (569 kN), it holds the record for the highest thrust (though it is rated at 115,300 lb_f (513 kN)). This thrust record was accomplished inadvertently as part of a one hour triple red-line engine stress test. In order to accommodate the increase in torsional stresses an entirely new steel alloy, GE1014, had to be created and then machined to extreme tolerances.

Developed from the 1970's NASA Energy Efficient Engine, the GE90 10-stage high pressure compressor develops a pressure ratio of 23:1, an industry record. The GE90-115B fan is an advanced design made from composite materials and featuring swept rotor blades.

At least one technical paper presented on behalf of one of GE's project partners indicates that further thrust improvement programs will be promoted should a market for higher thrusts arise. For comparison purposes, the Boeing 747-400's largest engines produce roughly 65,000 lb_f (289 kN) of thrust. It is therefore likely that the next version or successor of the Boeing 777 will be powered with a later version or derivation of this engine and will produce twice the thrust of the most powerful fitted to the venerable 747. Claims have been made that a single engine moves enough air to empty a building the size of the Madison Square Garden in one minute. The diameter of the engine (3.43 m) and nacelle are larger than the fuselage of a Boeing 737 (3.4 m).

They can only be airfreighted in assembled form by outsize cargo aircraft such as the Antonov An-124 'Condor', presenting unique problems if due to emergency diversions, a 777 was stranded in a place without the proper spare parts. If the fan is removed from the core, then they may be shipped on a 747 Freighter. As a consequence, it incurs high preventive maintenance costs to minimize such risks. On December 17, 2005 a GE90-94B failed on an Air France 777 flying from Seoul to Paris resulting in an unscheduled landing in Irkutsk, Siberia. A replacement engine was flown via an An-124 and the engines were exchanged. The cause of the failure is still under investigation [1].

A fan blade from the GE90-115B has been placed on display at the Museum of Modern Art in New York City, New York.

The GEnx engine that has been developed for Boeing's 787, 747-8 and certain versions of Airbus' A350 is derived from the GE90. Engine Alliance, a cooperative venture between GE Aircraft Engines and Pratt & Whitney, developed a separate GE90 derivative engine for the Airbus A380 called the GP7200.