Dogfight Over The Pentagon

By Philip Elmer-DeWitt

Think you have watched the cutting edge of aerospace technology at work in the gulf? Well, you haven't seen anything yet, say test pilots participating in the U.S. Air Force's Advanced Tactical Fighter program. Stowed in a secure hangar at California's Edwards Air Force Base are hand-built prototypes of what these pilots claim are the two hottest fighter planes ever made. The flyers should know. For three months, in separate flight tests, they have been putting the experimental aircraft, designated YF-22 and YF-23, through their paces: landing in crosswinds, performing stomach-churning 360 degrees rolls and blasting through the atmosphere at twice the speed of sound.

But the real high-stakes dogfight is largely being waged on paper. A manufacturing team led by Lockheed, maker of the YF-22, and another headed by Northrop, maker of the YF-23, have each submitted 15,000 pages of data to the Air Force in an effort to convince officials that each company's model is the best candidate to replace the F-15 Eagle, the 15-year-old long-range fighter that has been flying critical missions over Kuwait and Iraq. The Air Force is scheduled to choose between the two models on April 30. The winning team could take home an order for 750 planes priced at $35 million apiece. (A Navy version designed for carrier operations could yield orders for an additional 550 aircraft.) "It's a hell of a competition," says a congressional staff member. "It should be, considering the cost."

The planes, which cost over a billion dollars to develop, easily exceed the Air Force's stringent performance requirements. Both can cruise at supersonic speeds without having to resort to fuel-gulping afterburners, and they have twice the range of the F-15. The aircraft use advanced computerized controls and simplified screens to lighten the pilot's work load. Both candidates incorporate the latest radar-evading "stealthy" features. They pack as much as 20 times the data-processing power of an F-15 for spotting hostile aircraft before being seen themselves.

The planes have different strong points. Northrop's YF-23, with its sharp, surprising lines, may be stealthier. Its engines are slung under its wings, but their exhaust is sprayed into troughs on the wings' upper surfaces to shield from heat-seeking missiles, a technique borrowed from Northrop's B-2 Stealth bomber. The material surrounding the exhaust outlets in the YF-23 can withstand a temperature of 540 degrees C (1000 degrees F), while the undersurface only a few inches away never gets hotter than 140 degrees C (280 degrees F), making the plane hard to detect by enemy infrared sensors. The slightly smaller Lockheed YF-22 may be more maneuverable, thanks, in part, to nozzles that direct the thrust of the engines' exhaust this way and that. "Thrust vectoring," as this is called, helps push the plane through sharp turns at very high and very low speeds and lets it fly with its nose up at a sharp angle, enabling the pilot to direct weapons from almost any position.

Air Force officials say it is too early to tell which aircraft has the edge. They are still running computer models comparing each plane's performance against hypothetical aircraft that the Soviets might build. One wild card: a requirement tacked onto last year's authorization bill instructing the Air Force to determine whether it needs the Advanced Tactical Fighter at all or can instead make do with upgrades of its existing fleet of F-15s and F-16s. That report is expected in late April, about the same time the Air Force is scheduled to choose the plane it thinks will rule the skies into the next century.

With reporting by Jay Peterzell/Washington and Edwin M. Reingold/Los Angeles