General Electric F404

The General Electric F404, F412, and RM12 are a family of afterburning turbofan engines in the 10,500-19,000 lb_f (85 kN) class (static thrust). The series are produced by GE Aviation. 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.

F404 development

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 Light Weight Fighter competition to the P&W-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 .25 to .4 to enable higher fuel economy. In an unorthodox move, the Navy specified the requirements in order as:
#Operability
#Reliability and maintainability
#Cost
#Performance
#Weight

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 to 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 were 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.cite book |author=Kelly, Orr |title=Hornet: the inside story of the F/A-18 |location=Novato |publisher=Presido Press |year=1990 |id=ISBN 0-89141-344-8]

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.cite book |last = Jenkins |first = Dennis R. |title = F/A-18 Hornet: A Navy Success Story |publisher = McGraw-Hill |date = 2000 |location = New York |id =ISBN 0071346961 ]

GE developed the F110 for the Air Force as an alternative to the Pratt & Whitney F100for use on the F-16 and F-15 based on the F101 and used F404 technology. [http://www.geae.com/engines/military/f110/spotlight_lockheed.html] GE developed the F404-GE-402 to provide more power for the Swiss export models of the F/A-18. The engine was subsequently adopted by the Kuwait for their Hornets, and eventually by the U.S. on late-model C and D Hornets.

RM12 development

The Volvo Aero modification of the F404 consists increased performance, greater resistance to bird strikes and designed for single engine use safety criteria. [ [http://www.idg.se/2.1085/1.174315 IDG: Reaktionsmotor 12 - både vacker och stark] ]

60% of the engine parts are produced by GE and then shipped to Sweden for final assembly. The fan/compressor discs and case, compressor spool, hubs, seals and the entire afterburner are designed and produced in Sweden. Maximum thrust is 80.5/54 kN (wet/dry).

F412 development

GE evolved the F404 into the F412-GE-400 non-afterburning turbofan for the 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.

Applications

;F404:
* Boeing F/A-18 Hornet
* Boeing X-45 UCAV
* Dassault Rafale (during development)
* HAL Tejas (during development, and on initial prodution models)
* Grumman X-29
* Lockheed F-117 Nighthawk
* Korea Aerospace Industries T-50 Golden Eagle
* Singapore Aerospace A/TA-4SU Super Skyhawk (Singaporean upgrade)
* Northrop F-20 Tigershark
* Rockwell/MBB X-31
* FMA SAIA 90 - designed, but not built.

;Volvo RM12:
* Saab JAS 39 Gripen
* Israel Aerospace Industries Kfir-C2 "Nammer" - designed, but not built

;F412:
* A-12 Avenger II - never flown.

pecification (F404-GE-402)

jetspecs

type=Afterburning turbofan
length=154 in (3,912 mm)
diameter=35 in (889 mm)
weight=2,282 lb (1,036 kg)
compressor=Axial compressor with 3 fan and 7 compressor stages

Bypass ratio: 0.34:1
combustion=
turbine=1 low-pressure and 1 high-pressure stage
fueltype=
oilsystem=
power=
thrust=
*11,000 lbf (48.9 kN) military thrust
*17,700 lbf (78.7 kN) with afterburner
compression=26:1
aircon=
turbinetemp=
fuelcon=
specfuelcon=
*"Military thrust": 0.81 lb/(lbf·h) (82.6 kg/(kN·h))
*"Full afterburner": 1.74 lb/(lbf·h) (177.5 kg/(kN·h))
power/weight=
thrust/weight=7.8:1 (76.0 N/kg)

ee also

* General Electric F414

References

External links

* [http://www.geae.com/engines/military/f404/ GEAE F404]
* [http://www.volvo.com/volvoaero/global/en-gb/products/aircraft+engines/RM12/introduction.htm Volvo Aero RM12]
* [http://www.globalsecurity.org/military/systems/aircraft/systems/f404.htm F404 page on GlobalSecurity.org]