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Boeing, Lockheed Advance Respective JSF Designs (Apr. 25)



FORT WORTH, Texas---The Lockheed Martin Joint Strike Fighter (JSF) team completed a successful pressure test of its "fastenerless'' inlet duct design.

The all-composite duct offers major advantages in costs and operational capabilities by eliminating fastener penetrations through the inlet. This results in a smooth inner surface, providing excellent aerodynamic and signature performance and eliminating maintenance associated with fastener corrosion and fuel-leak repair.

"Compared to inlet ducts in today's operational fighter aircraft, we estimate the new duct can be produced in half the span time and at two-thirds the cost,'' said Frank J. Cappuccio, vice president and program manager of the Lockheed Martin JSF. "In addition, this duct features superior aerodynamics, radar cross-section, durability and lower weight. We have thus addressed all four pillars of the JSF program -- affordability, lethality, survivability and supportability.''

A combination of advanced composite material and process technologies allowed the fabrication of a cost-effective, one-piece duct segment that can be assembled in the JSF airframe with minimal fasteners. The pressure test was a major step toward validating the use of integral composite attach flanges to eliminate thousands of through-the-duct fasteners.

Testing was performed at Northrop Grumman's Air Combat Systems facility in El Segundo, Calif. Northrop Grumman is a principal member of the Lockheed Martin JSF team.

The duct was to be tested up to, and beyond, its ultimate load-carrying capability to correlate predicted and actual stress levels and confirm the expected failure mode. During the actual test, the duct resisted failure even at twice its ultimate design load, which approached the limits of the test fixture. At that point, the test was suspended and the duct was visually inspected with no visible evidence of failure.

"Not only did this duct-test article contain all the features we expect to see in production, but these details were fabricated using production processes and tooling,'' said Bill Coleman, Inlet Integration Demonstration team lead. "In addition to validating the structural integrity of the design, we also were able to validate the tooling philosophy and savings in fabrication cost and flow span.''

Lockheed Martin received one of two JSF Concept Demonstration contracts awarded by the Department of Defense in November 1996. The Lockheed Martin JSF team includes Northrop Grumman and BAE SYSTEMS. Flight evaluation of the demonstrator aircraft is scheduled to take place in 2000, with government selection of a single contractor for the Engineering and Manufacturing Development phase set for 2001.

Lockheed Martin is headquartered in Bethesda, Md., and is a global enterprise principally engaged in the research, design, development, manufacture and integration of advanced-technology systems, products and services. The corporation's core businesses are systems integration, space, aeronautics and technology services. (ends)









PALMDALE, Calif.---The Boeing Joint Strike Fighter One Team has successfully completed the first phase of engine runs for its X-32A concept demonstration aircraft. The smooth, uneventful operation of the engine in the aircraft confirmed all performance predictions and moves the X-32A closer to its first flight.

The Pratt & Whitney F119-614 engine ran at idle power to verify system integrity, then at all power settings, from minimum to maximum afterburner. The engine was powered up eight times over a six-day period. All propulsion-system components operated as designed and experienced no anomalies. Emergency system tests and emergency shutdowns also were performed, revealing no issues.

"Engine performance was excellent,'' said Ad Thompson, X-32 flight-test manager. "This first phase of engine runs goes a long way toward risk reduction and validating our simulations. The engine operated just as well in the aircraft as it did on the test stand. "This gives us further confidence that we're on the right path toward a safe and productive flight-test program,'' Thompson said.

Additional engine tests involving the vehicle management system, electro-magnetic interference and other aircraft performance requirements will be done before low-speed taxi tests are conducted in May. The X-32A is expected to fly this summer.

Boeing, the world's largest producer of fighter aircraft, is competing to build the JSF under a four-year concept demonstration phase contract with the U.S. Air Force, Navy and Marine Corps, and the British Royal Air Force and Navy. A winner is scheduled to be selected in 2001.

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Lockheed Martin TeamSuccessfully Tests JSF 'Fastenerless' Inlet Duct