GEnx

概要

The GEnx (General Electric Next-generation eXperience) is GE Aerospace's successor to the CF6 for the widebody market, developed concurrently for two very different aircraft: the Boeing 787 Dreamliner and the Boeing 747-8. Two distinct variants — GEnx-1B for the 787 and GEnx-2B for the 747-8 — share a common high-pressure core but differ significantly in their fan, low-pressure compressor, and turbine configurations to match each aircraft's thrust and airflow requirements. The GEnx delivers approximately 15% better fuel burn than the CF6-80C2 it replaces, driven by a higher OPR of 50:1, elevated turbine entry temperatures, and extensive use of composite materials throughout.

A landmark innovation on the GEnx is its composite fan case — the first on a large commercial engine. Combined with composite fan blades (18 per engine on the GEnx-1B, 22 on the GEnx-2B), the GEnx achieves significant weight reduction compared to its CF6 predecessor. The engine also incorporates a twin-annular premixing swirler (TAPS) combustor that reduces NOx emissions by approximately 50% compared to CAEP/6 standards, and a 5-stage low-pressure turbine using advanced airfoil profiles. The 787's all-electric architecture enabled GE to eliminate the engine bleed air system on the GEnx-1B, simplifying the engine and improving efficiency.

技術仕様

派生型

The GEnx-1B family powers the 787, with thrust ratings from 53,000 lbf (GEnx-1B54) through 76,100 lbf (GEnx-1B76A). The GEnx-1B64 and -1B67 are the primary variants for the 787-8, while the -1B70/P2, -1B74, and -1B76 serve the larger 787-9 and 787-10. The no-bleed architecture of the 787 required significant GEnx-1B redesign effort compared to conventional engines. The GEnx-2B powers the 747-8 with thrust around 66,500 lbf (GEnx-2B67); unlike the -1B, the -2B retains bleed air extraction for the 747-8's conventional pneumatic systems, and uses a larger fan and different LP system. The -2B has also been selected for the 747-8F freighter variant, supporting the cargo operations of UPS and other freight carriers.

搭載機

• Boeing 787-8: GEnx-1B64/67 (64,000–67,000 lbf) — Dreamliner launch variant, competing with Trent 1000
• Boeing 787-9: GEnx-1B70/74/76 (70,000–76,100 lbf) — stretched Dreamliner, best-selling 787 variant
• Boeing 787-10: GEnx-1B76A (76,100 lbf) — longest 787, high-thrust variant
• Boeing 747-8I: GEnx-2B67 (66,500 lbf) — Intercontinental passenger variant; also powers 747-8F freighter

開発の歴史

GE launched the GEnx in 2004 alongside Boeing's 787 program announcement. The first GEnx-1B engine test ran in February 2006 at Peebles. FAA certification of the GEnx-1B was achieved in July 2011, followed by GEnx-2B certification in August 2011. All Nippon Airways operated the first GEnx-powered 787-8 revenue flight in October 2011. An early service issue emerged in 2013 when some 787 operators experienced ice crystal icing in the engine's core at high altitudes, causing power rollbacks — a condition remedied through software and hardware modifications by 2014. The GEnx-2B entered service on the 747-8F with Cargolux in October 2011, and the passenger 747-8I with Lufthansa in June 2012. By 2024, GEnx had accumulated more than 90 million flight hours and achieved shop visit intervals exceeding 25,000 hours on mature engines, comparable to the exceptional CF6 reliability record it was designed to surpass.