EACH MORNING DURING THE SUMMER OF 2000, THE STILLNESS OF THE EVERGLADES was shattered by the thunder of an experimental propulsion system mounted 25 feet up on a test stand at a Pratt & Whitney facility in West Palm Beach, Florida. As the alligators stirred in the swamp, the engine roared away, hour after hour, week after week, while Lockheed Martin engineers watched nervously for signs of trouble in their intricate, classified design. All too frequently, they would shut the unit down as one mechanical problem after another dogged their efforts.
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First there were oil leaks. Then, a quarter-inch misalignment of two gears produced tiny metal shavings, which worked their way into the gearbox. Bearings failed and a nut wobbled loose. In most test programs, such failures would rank as little more than minor annoyances that ingenuity and patience would surely overcome. But the continual glitches only added to the highstakes gamble that Lockheed was already taking with its revolutionary new propulsion system: a massive lift fan weighing 1.5 tons. This was the company’s daring solution to one of aviation’s most daunting challenges: getting a supersonic fixed-wing airplane to take off and land vertically.
And in early 2000, the clock was ticking for the Lockheed team. At stake was a contract, worth at least $200 billion, to build the Joint Strike Fighter, a one-size-fits-all attack fighter for the Air Force, Navy, and Marine Corps. JSF program officers had already let Lockheed managers know that their chances of winning against Boeing, their rival in the competition, depended on the success of the lift fan. And Lockheed’s engineers were well aware that for all the brilliance of the lift fan concept, its mechanical complexity would be its Achilles’ heel.
In August 2000, propulsion and controls engineer Scott Winship received an ominous summons from Lockheed Martin’s president, Dain Hancock. “Dain dragged us all into his office,” Winship remembers, “because he knew that if we couldn’t finish our testing on time, the customer was going to pull us from the program. All we’d have to show for it would be this neat simulation, and we’d never get to fly. I’ll never forget, he said, ‘I want to look everybody straight in the eye and ask if you’re going to finish this program.’ My first thought was Well, maybe this is my last day at Lockheed. At the end of the meeting he handed us the scepter and said, ‘I want you to go do this!’ ” For Winship and his team, it was a make-or-break moment. “Thinking back, I bet half the people in the room didn’t believe we could make it. And the rest, like me, who were sticking their necks out, thought Yeah, I think we can.”
Boeing and Lockheed Martin’s epic duel began in two of Air Force Plant 42’s giant hangars, separated by less than a mile of runway and Death Valley desert scrub in Palmdale, California. In one building, the home of the Skunk Works, was Lockheed Martin’s team. Across the runway was a former Rockwell facility taken over by Boeing and filled with topdrawer engineering talent, some of it fresh from McDonnell Douglas after Boeing’s merger with the aerospace giant in 1997. The only visitors allowed inside both facilities were JSF program officers and a crew from the Public Broadcasting System’s NOVA series. (This was the first time TV access had ever been granted to a classified military development program. The NOVA documentary about the triumphs and heartbreaks of the JSF competition, on which this article is based, will air on January 14, 2003.)
The last attempt at building one fighter for both the Navy and the Air Force was in the early 1960s, when General Dynamics produced the F-111. After almost a decade of snarling, the Navy backed out of the deal, and the Air Force ended up with one of its most controversial fighters. Now Boeing and Lockheed faced the same danger: In trying to satisfy all three services, they could end up pleasing no one.
The Air Force demanded an agile and stealthy strike aircraft that would enable it to retire its F-16s. The Navy needed a replacement for its F-14s and F/A-18s sturdy enough to operate from a carrier deck. The Marine Corps was wrestling with the shortcomings of the short-takeoff-and-vertical-landing AV-8B Harrier. The Marines stipulated that, unlike the Harrier, their STOVL version of JSF had to be stealthy, supersonic, and able to bring back a 5,000-pound payload at the end of a mission. “When I took an initial look at the requirements,” recalls Boeing’s chief designer, Dennis Muilenberg, “it worried me. It was by far the most difficult set of requirements I’ve ever seen. It needs to do everything that conventional aircraft do. It needs to fly vertically, carry internal weapons; it also has to be low-signature; and, oh, by the way, it has to be very low cost and be much more supportable than previous aircraft. So yeah, I was worried.”
To overcome their greatest worry—STOVL capability—Muilenberg and his team chose the simplest, cheapest solution that had already been tested by an operational aircraft: the direct lift approach, pioneered by the British Aerospace Harrier. A direct lift system redirects the thrust from the engine through a series of downward-pointing nozzles on takeoff and landing. Muilenberg’s design involved channeling most of the thrust through two main lift nozzles close to the center of gravity, while additional nozzles at the wingtips and tail would help control the airplane’s attitude. Digital flight controls would manage the job of coordinating the hover control, eliminating the tricky handling that had made the Harrier such a nightmare for neophyte pilots.
But other drawbacks of the Harrier approach were not so easy to overcome. The total reliance on the engine for lift in takeoff and landing meant that weight was always a crucial factor. “Boeing was the first to get the cost message,” says Flight International reporter Graham Warwick, “and the simplicity of direct lift gave them a great rationale. But like the Harrier, their plane’s STOVL performance always depended on the engine. They were always asking for more thrust from the engine than Lockheed, and always fighting weight from day one. Though every aircraft test program fights weight, for Boeing it became their most critical factor.”
Lockheed’s solution to STOVL was the lift fan, a groundbreaking design that brought with it different kinds of headaches. The concept dates to 1987, when officials from the U.S. government’s Defense Advanced Research Projects Agency asked Skunk Works engineer Paul Bevilaqua to come up with a way to improve the Harrier’s performance. In his subsequent patent, Bevilaqua sketched out his idea: installing a pair of horizontal, counter-rotating fans that would provide a pillar of air for the airplane to hover and land on, in addition to the vectored thrust from the engine. But what would drive this extra source of lift? Bevilaqua had a “Eureka!” moment when he figured out an efficient way to extract additional power from the engine. This power was transferred to the lift fan by a drive shaft that projected from the front of the engine. The drive shaft had to make a 90-degree turn to the horizontal fan via a clutch and gearbox similar, in principle, to those of an automobile.