CONTRACTS TO EXPLORE the feasibility of a next-generation advanced short take-off and vertical landing (ASTOVL) aircraft for the USAF/USN/USMC have been awarded to Lockheed and McDonnell Douglas by the United States Advanced Research Projects Agency. Two three-year contracts were awarded, Lockheed Advanced Development company being asked to develop a shaft-driven lift-fan concept in its $32.9 million contract, while the McDonnell Douglas Aerospace $27.7 million contract is for examination of an exhaust gas-driven design. A full-scale model will be built of each design, including a working engine, for testing in the NASA Ames Research Center wind tunnel from early 1995. Unsuccessful bidders for the contracts were General Dynamics, Grumman and Rockwell.
Lockheed will base its design around the Pratt & Whitney Fl19 super cruising turbofan, mechanically connected to a lift fan vertically-mounted just behind the cockpit which will augment the main engine thrust, enabling very short take-offs and vertical landings. An engine consortium will be led by P & W, with Allison providing the lift fan section and Rolls-Royce the lift components.
McDonnell Douglas will utilise a variant of the General Electric YF120 powerplant to be developed in conjunction with Rolls-Royce. British Aerospace will also partner McDonnell Douglas in the project. Its design will duct some of the exhaust gas from the main variable-cycle engine to power the lift fan.
USAF, Navy and Marine Corps requirements are all for a similar single-engined, single-seat, non-afterburning supersonic strike fighter with stealth qualities. The USAF variant would be a conventional take-off fighter to replace the F-16, while the USN/USMC variant would supplant the F-18 Hornet and AV-8B Harrier. Novelised versions, also referred to as the short take-off/vertical landing strike fighter (SSF), would be optimised for carrier operations and include propulsive lift hardware and software to make catapults and arrester gear unnecessary.
Interest in the project has also been expressed by the Royal Navy which would be looking at ASTOVL as a potential replacement for the Sea Harrier FRS.2. It is anticipated that, subject to continued funding for the development programme, the SSF/ASTOVL could be in service by 2010.