X-32B completes government flight-test requirements
3 July 2001
The Boeing Joint Strike Fighter programme has completed all of its government-defined flight-test requirements. The programme reached the final milestone Sunday by making a series of short takeoffs at Naval Air Station Patuxent River in Maryland.
The X-32B concept demonstrator has validated the Boeing solution to the program's short-takeoff-and-vertical-landing (STOVL) requirements. Having now met all the defined requirements, including a flight in which the aircraft took off in less than 550 feet of roll, Boeing will continue performing a series of short takeoffs at successively shorter runway lengths.
For the short takeoff, Boeing lead STOVL test pilot Dennis O'Donoghue accelerated the X-32B down the runway to a speed of 80 knots, then pushed a throttle-mounted flow-switch button that redirected engine thrust from the cruise nozzle to lift nozzles in the underside of the airplane. The lift nozzles were preset at a position of 60 degrees aft.
When the plane reached 150 knots and approximately 750 feet of altitude, O'Donoghue redirected the thrust back through the cruise nozzle to complete the transition to conventional flight. The X-32B then completed a number of tests before landing.
"This STOVL milestone is further proof of the ease and low pilot workload associated with direct lift,'' O'Donoghue said. "The Boeing direct-lift system enables me to simply push a button and switch the thrust from the cruise nozzle to the lift nozzles in one second and at any power setting.''
"This is among the most significant achievements in the programme to date,'' said Frank Statkus, Boeing vice president and JSF general manager. "Our innovative flight-test methods, modelling and simulation, and flight-test software tools have contributed to outstanding efficiency and an unheard-of sortie rate for conventional aircraft, much less for a concept-demonstrator aircraft.''
Statkus also praised the X-32B's Pratt & Whitney engine and Rolls-Royce lift system. "The demonstrated robustness and reliability of the Pratt & Whitney/Rolls- Royce propulsion system has been key to the success of our X-32B STOVL operations. The engine has been rock steady in all aspects of flight operations, including both the physical interaction with the airplane and the functional integration with the flight control system.''
Having completed all customer requirements, which include transition to and from vertical flight, hover, vertical landing and short takeoff, Boeing will carry out its own objectives before concluding the X-32B flight-test programme later this month.
REF XQQAS XQQAR