The General Electric F404 and F412 are a family of afterburning turbofan engines in the 10500- class (static thrust). The series is produced by GE Aerospace. Partners include Volvo Aero, which builds the RM12 variant. The F404 was developed into the larger F414 turbofan, as well as the experimental GE36 civil propfan.
GE developed the F404 for the F/A-18 Hornet, shortly after losing the competition for the F-15 Eagle's engine to Pratt & Whitney, and losing the Lightweight Fighter (LWF) competition to the Pratt & Whitney F100 powered YF-16. For the F/A-18, GE based the F404 on the YJ101 engine they had developed for the Northrop YF-17, enlarging the bypass ratio from 0.20 to 0.34 to enable higher fuel efficiency. The engine consists of a three-staged fan, seven axial stage compressor arrangement, single stage low and high pressure turbines, an afterburner, and produces maximum thrust of 16,000 lbf (71.2 kN) in the original F404-GE-400 model. The engine was designed with a higher priority on reliability than performance. Cost was the main goal in the design of the engine.[1]
GE also analyzed "throttle profiles" and found that pilots were changing throttle settings far more often than engineers previously expected, putting undue stress on the engines. GE also sought with the F404 a design that would avoid compressor stalls and other engine failures, and would respond quickly to control inputs; a common complaint of pilots converting from propeller planes to jets was that early turbojets were not responsive to changes in thrust input. GE executives Frederick A. Larson and Paul Setts also set the goal that the new engine would be smaller than the F-4's GE J79, but provide at least as much thrust, and cost half as much as the P&W F100 engine for the F-16.[2]
Due to a fan designed to smooth airflow before it enters the compressor, the F404 has high resistance to compressor stalls, even at high angles of attack. It requires less than two shop visits per 1,000 flight hours and averages 6,500 hours between in-flight events. It also demonstrates high responsiveness to control inputs, spooling from idle to full afterburner in 4 seconds. The engine contains an in-flight engine condition monitoring system (IECMS) that monitors for critical malfunctions and keeps track of parts lifetimes.[3]
GE developed the F110 for the Air Force as an alternative to the Pratt & Whitney F100 for use on the F-16 and F-15 based on the F101 and used F404 technology.[4] The F110 was derived from the F101 via the F101DFE, though some elements of the F404 such as the design of the fan, albeit enlarged, were incorporated, per the F110 page and other sources. GE developed the F404-GE-402 in response to a Swiss requirement for more power in its F/A-18 version; it produces a maximum of 17,700 lbf (78.7 kN) of thrust with afterburner. The new engine version was used on Kuwaiti Hornets, later U.S. C and D Hornets, and subsequent Hornets.[5] The KAI T-50 Golden Eagle uses a single General Electric F404-GE-102 turbofan engine with Full Authority Digital Engine Control (FADEC) system; the engine is similar to the F404-402, but with additional redundancies built in for single-engine operations. The aircraft has a maximum speed of Mach 1.5.
Almost 4,000 F404 engines power the F/A-18 Hornets in service worldwide. The F404 engine family had totaled over 12 million flight hours by 2010.[6]
For HAL Tejas Mk 1A, GE developed an uprated F404-IN20, which is the highest thrust variant in F404 family, and which produces a maximum of 19,000 lbf (84 kN) of thrust with afterburner.[7] It incorporates latest hot section materials and technologies as well as FADEC system for reliable power and performance. On 17 August 2021, India signed a contract with GE worth to supply 99 F404 engines and service support by 2029.[8] However, the delivery of the first engine is yet to be delivered as of July 2024 which has led to the delay of delivery of HAL Tejas Mk1A aircraft to the Indian Air Force. Afterwards, reports suggested that engine delivery is expected to commence from September 2024 at the rate of 1-2 per month.[9] [10]
GE developed the F404 into the F412-GE-400 non-afterburning turbofan for the McDonnell Douglas A-12 Avenger II. After the cancellation of the A-12, the research was directed toward an engine for the Super Hornet, which evolved into the F414.