The General Electric GE90 is a family of high-bypass turbofan aircraft engines built by GE Aerospace for the Boeing 777, with thrust ratings from 81,000 to 115,000 pounds-force (360 to 510 kilonewtons).

It was the largest jet engine,[3] until being surpassed in January 2020 by its successor, the 110,000 lbf (490 kN) GE9X, which has a larger fan diameter by 6 inches (15 cm).

In the early 1980s, GE began to develop an unducted fan (UDF) engine, which was thought to be a more fuel-efficient option to propel short-haul airliners, a compelling proposition after the 1979 oil crisis.

One of the major innovations for the engine were its carbon fiber composite fan blades, which were both lighter and stronger than traditional materials.

[10] The GE90's 10-stage high-pressure compressor developed a then-industry record pressure ratio of 23:1 and is driven by a 2-stage, air-cooled, HP turbine.

General Electric incorporated an advanced larger diameter fan made from composite materials which enhanced thrust at low flight speeds.

However, GE also needed to increase core power to improve net thrust at high flight speeds.

[14][17] For Boeing's second-generation 777 long-range versions (777-200LR, 777-300ER, and 777F), greater thrust was needed to meet the aircraft requirements.

[18] The higher thrust GE90-110B1 and -115B engines, in combination with the second-generation 777 variants -200LR and -300ER, were primary reasons for 777 sales being greater than those of the rival A330/340 series.

[24] In July 2020, the fleet of 2,800 engines surpassed 100 million hours, powering over 1,200 aircraft for 70 operators with a dispatch reliability rate of 99.97%.

To accommodate the increase in fan-shaft torsional and bending stresses, a steel alloy, GE1014, not previously used in aircraft engines was required.

[30][31] In October 2003, a Boeing 777-300ER broke the ETOPS record by being able to fly five and a half hours (330 minutes) with one engine shut down.

[33] On August 11, 2004, a GE90-85B powering a Boeing 777-200ER on British Airways flight 2024 suffered an engine failure on takeoff from George Bush Intercontinental Airport, Houston.

[34] On May 28, 2012, an Air Canada 777-300ER taking off from Toronto en route to Tokyo suffered failure of a GE90-115B at 1,500 feet (460 m) and returned safely.

[35][36] On September 8, 2015, a GE90-85B powering a Boeing 777-236ER on British Airways Flight 2276 suffered an uncontained failure during take-off roll at Las Vegas McCarran Airport, leading to a fire.

[39] The FAA issued an Airworthiness Directive (AD) on May 16, 2013, and sent it to owners and operators of General Electric GE90-110B1 and GE90-115B turbofan engines.

This emergency AD was prompted by reports of two failures of transfer gearbox assemblies (TGBs) which resulted in in-flight shutdowns (IFSDs).

This condition, if not corrected, could result in additional IFSDs of one or more engines, loss of thrust control, and damage to the airplane.

In February 2012, GE announced studies on a 10% more efficient derivative, dubbed the GE9X, to power the new Boeing 777-8X/9X aircraft.