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F-35 Acquisition





Title: History

The selection of Lockheed Martin and Boeing for the concept demonstration phase was made in early 1997. McDonnell Douglas was eliminated and their team was dissolved. In the spring of 1997 Northrop Grumman joined the Lockheed Martin team and at the 1997 Paris Airshow, British Aerospace was added.

The Concept Definition Phase of the program saw the name changed to Joint Strike Fighter, with a mandate to develop flying demonstrators for possible production.

Between the CDP contract award in 1996 and the first flights in 2000, literally thousands of meetings and technical reviews took place as the Boeing and Lockheed teams worked towards finalizing the designs for their X demonstrator aircraft and continued refining what would become their final program proposals.


Boeing X-32 Test Flights
Fred Knox, Boeing JSF Chief Test Pilot, piloted the X-32A as it departed the runway at Palmdale on its first flight at 10:00 am PST on 18 September 2000. During the flight, Knox put the X-32A through some initial airworthiness tests, including flying qualities and sub-systems checkout. The first flight represented the X-32A's entry into a five-month flight-test program at Edwards Air Force Base that consisted of approximately 50 test flights totaling about 100 hours to validate the X-32’s flying qualities and performance for conventional and aircraft carrier operations.

On 15 November 2000, the X-32A began field carrier landing practice (FCLP) tests to demonstrate flying and handling qualities during low-speed aircraft carrier approach. U.S. Navy Commander Phillip “Rowdy” Yates, the U.S. government's lead test pilot for the Boeing JSF program, and Knox demonstrated simulated carrier landings using a Fresnel lens to provide pilot cues during their approaches to a simulated carrier deck outlined on a runway at Edwards Air Force Base. The tests were successfully concluded on 2 December.

Boeing CV accomplishments included 97 approaches and 74 actual touchdowns, as well as numerous "wave-offs," throttle transients and integrated test blocks including roll response and speed stability during the FCLP tests. Flying as many as five flights a day the week of 18 December, the X-32A successfully completed low-speed approach CV tests, marking completion of 100% of the government-defined CV test objectives.

The X-32B took to the air for the first time on 29 March 2001, the pilot was Phil O'Donoughe. The aircraft conducted a 50-minute conventional flight from Palmdale to Edwards Air Force Base. During the flight the X-32B was subjected to a series of initial airworthiness tests, including flying qualities and subsystems checkout.

Following the conclusion of several in-air STOVL tests, the X-32B was prepared for its ferry flight to Patuxent River Naval Air Station (NAS), MD. The X-32B departed Edwards AFB for its cross-country trip on 4 May. While en-route to NAS Patuxent River, the X-32 made six refueling stops, as it was not certified for air-to-air refuelings. The X-32B arrived at Patuxent River NAS on 11 May.

On 24 June, during the aircraft's 44th flight, O’Donoghue transitioned the X-32B from fully wingborne (conventional) to jetborne (STOVL) flight mode and then smoothly decelerated the X-32B to a steady hover at about 250 feet above the ground. O'Donoghue then accelerated out of the hover and transitioned back to conventional flight before making a "slow landing." During four other flights the same day, the X-32B completed three additional hovers and numerous transitions to STOVL flight. In total, the X-32B hovered for eight minutes that day, the single longest sustained hover covering two minutes and 42 seconds.

The final flight of the X-32B test program occurred on July 28, 2001. The aircraft took-off at 1547 EST, climbed to 30,000 feet and performed a series of supersonic dashes achieving a maximum speed of 1.05 Mach. UK Royal Navy test pilot Lieutenant Commander Paul Stone, guided the aircraft to touchdown at 1628 EST thus bringing to a close the Boeing flight test program.


Lockheed X-35 Test Flights
The X-35A CTOL demonstrator successfully completed first flight on 24 October 2000, taking off at 9:06 a.m. Pacific Daylight Time from Palmdale. The initial flight profile included check-outs of the on-board systems, handling characteristics and down-link connections for the constant stream of critical data-transfer to the flight-test technicians at Palmdale and Edwards Air Force Base. The X-35 climbed quickly to an altitude of 10,000 feet, maintained an airspeed of 250 knots while accomplishing a series of figure-eight maneuvers to demonstrate key handling qualities and to validate design predictions.

The X-35A CTOL program was completed on 22 November 2000 with all objectives achieved or exceeded.

The X-35A (aircraft 301) made its last flight to Palmdale, where it immediately began conversion to the X-35B STOVL variant. The flight LiftFan 3D had just arrived at Pratt & Whitney for acceptance testing from Rolls Royce North America.

At 9:23 a.m. PST on 16 December 2000, Lockheed test pilot Joe Sweeney launched the X-35C from the Lockheed Martin Aeronautics plant in Palmdale, Calif., and flew the plane for 27 minutes before touching down at Edwards Air Force Base. The aircraft climbed to 10,000 feet and accelerated to 250 kt (288 mph). Sweeney cycled the landing gear and performed aircraft flying-qualities evaluations, including rolls, sideslips, and overall systems checks. Primary differences from the X-35A include a larger wing and control surfaces, the addition of ailerons and a special structure to absorb high-impact landings. Two additional flights took place on 19 December in preparation for commencement of FCLP testing.

The Lockheed Martin JSF team completed installation of the JSF X-35B’s flight-ready propulsion system – including the shaft-driven lift fan and engine – on May 12. Following these modifications, the aircraft was towed to the hover pit and British Aerospace test pilot, Simon Hargreaves began operating the flight-ready system in the aircraft on May 24.

On 23 June 2001 at the Lockheed Martin Skunk Works in Palmdale, the X-35B conducted its first press-up, marking the first time in aviation history that a shaft-driven lift fan propulsion system had lifted an aircraft into the sky. On that day, Hargreaves took the aircraft up to 15-20 ft for several minutes and then conducted a vertical landing. The following day, Hargreaves again engaged the LiftFan propulsion system, and the plane rose straight up to a stabilized position at an altitude of about 25 ft, while Hargreaves checked to ensure the flight controls responded properly before returning the plane gently to the ground.

On 06 August 2001, during the aircraft’s 66th and final test flight, Tom Morgenfeld piloted the X-35B. The aircraft left the runway at Edwards AFB at 1009 PST. Several test cards were performed and the aircraft was ferried back to Palmdale for storage. The flight lasted 3.7 hours, during which Morgenfeld went through six aerial refuelings. Six touch and go landings were conducted at Palmdale before Morgenfeld brought the aircraft to rest. At the end of its testing, the total amount of flight time on the X-35B was 48.9 hours.

Following the completion of their flight test periods, the X-35 demonstrator aircraft were retired to museums. The X-35A/B is now in the permanent collection of the Smithsonian Institution and is on display at the Stephen F. Udvar-Hazy Center near the Dulles International Airport in Virginia. The X-35C is now in the permanent collection of the United States Association for Naval Aviation and is on loan to the Patuxent River Naval Air Museum in Lexington Park, Maryland.


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