EVENDALE, Ohio - The team of GE Aircraft Engines, Allison Advanced Development Company, and Rolls-Royce Military Aero Engines Ltd. (R-R) is engaged in detailed design work that will lead to full engine testing early next century for the U.S. Joint Strike Fighter (JSF) Alternate Engine Program.
Earlier this year, the JSF Program Office awarded the GE/Allison/R-R team a $106 million, four-year, Phase II contract for the Alternate Engine Program. The contract covers airframe integration studies, core engine detailed design, engine hardware procurement, engine diagnostics development, and technology maturation. With this contract, the JSF program will attain life-cycle cost benefits through competition, and will realize improved weapon system readiness and enhanced risk reduction.
At the conclusion of Phase II, the team will run a core engine test at Allison's Indianapolis, Indiana, facility. A follow-on turbofan development program is expected to begin in 2001, followed by full-engine testing. This is expected to lead to a full-scale engineering and manufacturing development contract in 2004.
In 1996, the JSF office selected the GE YF120 as the baseline engine from which to develop derivatives for the Alternate Engine Program. The selection was based on the engine's core thrust capability to meet the multi-service (U.S. Air Force, U.S. Navy, U.S. Marine Corps., U.K. Royal Navy) aircraft requirements, including STOVL (short takeoff and vertical landing) capability without scaling, and for its growth potential. Designated the YF120-FX for the JSF, the engine is based on the GE YF120 developed and successfully demonstrated in flight in the early 1990s for the USAF's Advanced Tactical Fighter engine competition.
For the YF120-FX engine, GE, Allison, and R-R formed a world-class team combining GE's expertise in single-engine fighter safety, performance, and low observable inlet/exhaust system components with Allison's high performance components and cooling technologies, and R-R's extensive experience in V/STOL and fan development and manufacturing technologies.
GE, the lead systems integrator, is developing a multi-stage blisk compressor, radial augmentor and dual control system (derived from GE's F414 engine), and advanced exhaust nozzle. Allison and GE are jointly developing a coupled turbine system (an integrated HP/LP counter-rotating design) incorporating advanced cooling technology. In addition, Allison is responsible for the combustor/diffuser system and the gearbox.
R-R, which joined GE and Allison on the JSF in early 1996, will design and manufacture the increased-airflow, three-stage, long-chord blisk fan.
As part of the JSF technology maturation effort, the GE LO Axi (Low Observable Axisymmetric) Exhaust System successfully completed ground testing on an F110-GE-100 engine on an F-16 aircraft, operating from idle to maximum afterburner. The infrared (IR) and radio-frequency (RF) test data confirmed the achievement of installed signature goals during operation. Nozzle system demonstration continues with a 500-hour durability test on an F110-GE-129 currently in process.
The LO Axi Nozzle achieves signature levels comparable with other complex exhaust systems, although the LO Axi Nozzle is an inherently lower-weight, lower-cost, and structurally simpler system. It will reduce maintenance time requirements by as much as 60 to 90 percent, compared to current exhaust system components.
In addition to the JSF Phase II Program, GE and Allison are jointly developing technologies through the U.S. Department of Defense's Integrated High Performance Turbine Engine Technology (IHPTET) initiative that will be applicable to the JSF.
GE and Allison have been teamed since 1993 on IHPTET technology programs to demonstrate affordable propulsion capability improvements and higher temperatures. In early 1998, Allison and GE's Advanced Turbine Engine Gas Generator (ATEGG) core engine will undergo testing. The engine features a metal matrix composite compressor and a high-pressure turbine with advanced cooling technology. In late 1998, the GE/Allison Joint Technology Demonstrator Engine (JTDE) will go to test to evaluate metal matrix components, advanced fan and controls technology, as well as a counter-rotating turbine system.
"The GE/Allison/R-R approach to the JSF Alternate Engine Program is a dynamic, multi-faceted effort," said Mearl Eismeier, JSF team program manager for the GE/Allison/R-R team. "By incorporating the expertise of three companies through internally and externally funded initiatives, we are developing technology with a focus on flexibility, affordability, and readiness."
GE Aircraft Engines is based in Evendale, Ohio (USA); Allison, in Indianapolis, Indiana (USA); and Rolls-Royce Military Aero Engines Ltd., in Bristol, England.