For Lockheed Martin Corp., Northrop Grumman Corp., and Britain's BAE Systems PLC, the celebrating is over. In late October the three-firm team, led by Lockheed Martin, won the competition with Boeing Corp. to pursue the next phase of the Joint Strike Fighter (JSF) program -- potentially worth $200 billion, the biggest defense contract ever in terms of dollars. But now comes the hard part. In previous phases of the project, the partners successfully designed and demonstrated an experimental version of the futuristic, single-airframe-design fighter that will be used in three variations by the U.S. Air Force, Navy and Marines, as well as by the United Kingdom. Now the program enters what is known as the System Development & Demonstration (SDD) phase. In many respects it's the most difficult phase. "Lockheed Martin and its partners have to firm up the design, detail all components, put in the manufacturing process, and the supply chain to support it," says Michael Burkett, senior research analyst at AMR Research, a Boston technology consultant. "Managing all that will be tremendously challenging. All the while the Defense Department will be pressuring them to meet the cost objectives -- and be on time." To help meet that challenge, the three companies are relying on an array of advanced manufacturing technologies. "We're using a lot of neat stuff," says Martin McLaughlin, a Northrop Grumman executive who heads the partnership's JSF airframe integrated product team in Fort Worth, Texas. The technologies, he indicates, represent "the best of the best" that have been gleaned from team members and suppliers. "The foundation of it all," McLaughlin says of the team's manufacturing approach, "is our use of 3-D solid modeling digital definition of the aircraft." Although Northrop Grumman's B-2 bomber was the first to be designed in 3-D, it was modeled with a wire system, not solid. But the solid system, McLaughlin says, "changes manufacturing. We flow this digital definition of the product through all phases of tooling, fabrication, assembly and even support." Notably, McLaughlin says, the technology "has revolutionized the machining of parts" by driving computer-based numerical-control machining processes. Among other things, this makes possible high-performance machining of aluminum and titanium. The technology also helps Lockheed Martin and its partners overcome what analysts cite as one of the JSF's daunting production challenges: achieving more precise control of composite materials. In a process called laser imaging, for example, "lasers in the factory ceiling can read the 3-D solid-model data and project directly onto a machine tool an outline of exactly where the mechanic should place the next ply of composite material," McLaughlin says. "It cuts lab time in half." Similarly, the companies are employing ultrasonic laser inspection of composite parts -- a technology that trims inspection time by a stunning 90%. They're also using what's called "laser trackers technology" to rig assembly fixtures digitally. "Until now, we've had neither the technology to build the parts accurately enough nor the digitally controlled assembly process to get parts to fit," McLaughlin notes. "We've had to make adjustments during assembly." Thanks to these and other technologies, the Lockheed Martin team will need 90% fewer tools to fabricate and assemble the JSF than previously required for an equivalent-weight aircraft. "We'll have less than half the number of parts," says McLaughlin. "And we'll have to install less than half the number of fasteners -- the highest source of errors in the field and in maintenance. Our manufacturing flow span will be reduced by two-thirds." Also vital to the partners' approach, says analyst Burkett, is their use of collaborative engineering computer technology that enables them and their suppliers to share design data and program information. Among key software suppliers for this task are Electronic Data Systems Corp., Plano, Texas, and Parametric Technology Corp. (PTC), Needham, Mass. "The scale of this program is unprecedented," says Mike Brown, PTC senior vice president. Currently, 67 U.S. and 18 international subcontractors are involved in the SDD phase, and more are expected to be added. Principal subcontractors, besides various units of the partners, are TRW Inc., Honeywell International Inc., BF Goodrich Co., Hamilton Sunstrand Corp., Vision Systems International and a Moog Inc. and Parker Hannifin Corp. team. The SDD contract won by the Lockheed Martin team, worth $18.9 billion, calls for it to build and demonstrate 22 aircraft. (Another contract of more than $4 billion went to Pratt & Whitney to develop engines.) First test aircraft are slated to fly in 2005; the first operational aircraft in 2008. Plans call for 3,000 of the fighters to be built by 2040. The Pentagon and Congress will decide later who gets the full production contracts, but unless it fouls up in the SDD phase, the Lockheed Martin team seems sure to win most -- or all -- the work. "The game is theirs to lose," says Daniel Shine Jr., an aerospace and defense consultant, A.T. Kearney Inc., Cambridge, Mass.