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Engines · GE Aerospace

GE90 and GE9X

GE90-115B, GE9X-105B1A

GE90 in service, GE9X in production 4 min read · updated 16 October 2026 · checked 21 October 2026

Two independent sources on every claim.

Turbofan model under test
An ultra high bypass ratio turbofan model in a NASA wind tunnel. Credit NASA.

At a glance

Engine card

VariantsGE90-115B, GE9X-105B1A
ArchitectureTwo shaft turbofan. 128 inch fan on the GE90, 134 inches on the GE9X
Thrust115,000 lbf on the GE90-115B, 110,000 lbf on the GE9X
Applications777 and 777F on the GE90, 777X on the GE9X
Built byGE Aerospace
StatusGE90 in production under waiver, GE9X in production

Program and production

These two engines are a generation apart on the same airframe family, and both are waiting on Boeing rather than the other way round.

The GE9X received FAA certification in 2020 and the first production engine was delivered to Boeing in 2024. The engine has been ready for years. The 777-9 has not: the FAA has signalled it will not certify the aircraft in 2026, pushing certification and first delivery into 2027, roughly seven years behind the original plan. Boeing has mostly attributed the delay to the certification process itself rather than to a new technical issue, though one engine specific problem has entered the picture since. GE Aerospace said in September 2026 that wear in a mid-seal inside the GE9X was holding up the extended range twin engine operations, or ETOPS, test campaign, the long-haul certification work that lets a twin-engined aircraft fly routes far from a diversion airport. GE redesigned the seal, began shipping engines with the new part to Boeing in the third quarter, and says FAA certification of the redesigned part is expected within a few months. Boeing chief executive Kelly Ortberg said ETOPS authorisation should follow soon afterward. Both companies maintain the issue should not push the programme beyond its already revised 2027 timeline.

Meanwhile the older engine got a reprieve. The FAA approved Boeing's request for an exemption from the ICAO emissions standard taking effect on 1 January 2028, which would otherwise have stopped new 777F certificates of airworthiness from that date. The exemption allows up to 35 more 777Fs to be sold through 1 January 2031, bridging the gap until the 777-8F arrives. Since the 777F is currently the only large widebody freighter in production, that waiver keeps GE90 production running years longer than planned.

Technical and maintenance

In plain terms

Additive manufacturing, often called 3D printing, builds a part up in layers from powder rather than machining it from a block or casting it. It allows internal shapes that cannot be machined, such as cooling passages inside a turbine part, and it lets several components be made as one piece. Around 300 parts in each GE9X are made this way.

On the line

On the GE90, the maintenance story is now about age rather than new findings. The 777-200ER fleet in particular is being flown well past the point many operators planned to retire it, because 787 and 777X deliveries have not arrived. Work that would have been deferred to end of life now has to be done properly, and GE90 shop visit scheduling deserves earlier planning than it did five years ago. On the GE9X, expect the usual early service learning curve once the fleet starts accumulating hours, and treat initial published intervals as provisional.

GE Aerospace has also extended its AI enabled Blade Inspection Tool, already running on the GEnx for about three years, to the GE9X and the CFM LEAP. The tool reviews borescope imagery and flags frames that need a closer look rather than making the call itself. GE reports inspection time cut from around three hours to ninety minutes, with improved accuracy against a standard borescope read.

Applications and fleet

The GE90-115B is the sole engine on the 777-300ER, 777-200LR and 777F, which is why its fate is tied so directly to Boeing's freighter line. The GE9X is the sole engine on the 777-8, 777-9 and 777-8F.

Sole source on both generations means GE carries no competitive risk on this airframe, but also that it absorbs the full cost of every programme delay. Seven years of 777X slippage is seven years of deferred GE9X revenue.

The first 777-8F rolled out of final assembly at Everett in April 2026 for Cargolux, with first delivery targeted for 2028.

Safety

No significant developments since 11 October 2026.

No Airworthiness Directive of fleet wide significance was issued against either engine in this period.

Sources