Winner Take All
All the nail biting, second guessing, and sheer engineering brilliance in the battle to build the better Joint Strike Fighter.
- By Evan Hadingham
- Air & Space magazine, January 2003
Heather Greasley/Lockheed Martin
(Page 4 of 5)
Knox flipped a switch and the engine roared to life. At the edge of the runway, Boeing engineers cheered. “Very shortly after liftoff,” Knox said, “it was absolutely clear to me that I was flying the airplane we had designed, built, and that I had been simulating for several years.”
Dennis O’Donoghue, a second JSF test pilot, following behind Knox in an F/A-18, was in shock. “Fred was flying at military power with no afterburner,” he said. “But he started climbing like a rocket. It was incredible: He was just gone. I had to use full afterburner, and only caught up with him at 10,000 feet.” Although the X-32A sprang a hydraulic leak and was ordered back to Palmdale, the test program was off to an auspicious start.
A month later, Lockheed caught up as its demonstrator, the X-35A, got off the ground. But the most crucial flight trial confronted Lockheed the following summer. Early on Sunday, June 24, 2001, JSF program manager Rick Baker nervously joined the lift fan’s godfather, Paul Bevilaqua, and its two key problem-solvers, Winship and Rezabeck, at the edge of the Palmdale runway. Former Harrier pilot Simon Hargreaves, a British test pilot, was about to nurse the X-35B STOVL version and its lift fan into the air for the first time.
“At the time, we were just supposed to be doing ‘press-ups,’ where Simon was going up to only five feet,” says Baker. “And he did five feet—we watched the wheels come off the ground and my heart started beating faster. Then he went up 10 feet and came down again so we could measure things like fuel temperature and heat. And then he went up and up to 50 feet and he held it. We looked at each other and said, ‘The Skunks did it again!’ and we hugged everybody. That was the real turning point. We knew the magic of the Skunk Works was still there.”
The lift fan’s success dashed Boeing’s hopes of an easy JSF victory. Yet the very same day at the testing base at Naval Air Station Patuxent River in Maryland, Boeing’s X-32A completed its first hover. As flight testing continued, with Boeing sometimes flying five missions a day and performing nearly flawlessly, the competition remained too close to call. Only a major slip would make one team the obvious winner.
At 1,500 feet over Patuxent River, Dennis O’Donoghue turned the X-32B downwind to prepare for its first vertical landing. As he brought Boeing’s STOVL demonstrator down to a stable hover at around 150 feet, he flicked a switch that turned on the jet screen—a narrow slot under the fuselage that blew cool engine bleed air toward the ground, helping to balance the airplane in hover and prevent the engine from sucking in its own exhaust.
By now brimming with confidence in the demonstrator’s handling qualities, O’Donoghue brought the X-32B gently down over the hover pit, a cavity in the runway designed to keep the exhaust from blowing back into the engine and minimize ground effect. The airplane coasted down to 40 feet, then O’Donoghue abruptly felt the bottom drop out underneath him. He jammed the throttle full forward and a red engine light flicked on, the automated voice he had hoped never to hear barking: “Warning, Warning, Engine, Engine.” Red lights were flashing in the control room too, and flight controller Howard Gofus tensely ordered O’Donoghue to abort the landing. But O’Donoghue was already at full power, and there was nothing more he could do. Bracing himself for a crash, he radioed, “I’m coming down!”
Then, with only seconds to spare, he got a reprieve. With around 20 feet to go, the engine recovered and the cockpit warnings ceased. The X-32B slowed its descent until it made a gentle touchdown at almost precisely its targeted landing speed. For the onlookers who rushed forward to congratulate O’Donoghue, it appeared to be a normal landing. Only Gofus and his team in the tower knew about the close shave, and they quickly figured out what the problem was. The wind that normally helped clear exhaust from the hover pit had momentarily died, and as the X-32B came down, its own exhaust gases had risen up from the walls of the pit and been sucked into the engine.