Not all factors are positive, however. Even though the fighter’s design is still being firmed up, Pentagon and service officials already are wrangling about how many F-35s will be built, who will get them, and when—despite the fact that those decisions don’t need to be made final for more than a decade.
The F-35 goes into preliminary design review on time and within the budget set at contract award 17 months ago, according to Maj. Gen. John L. Hudson, JSF program director. The aircraft is to be used by the Air Force, Navy, and Marine Corps, as well as the Royal Air Force, Royal Navy, and likely the air arms of nine other countries—so far.

“ We wanted to do a ‘fast break,’ ” Hudson told Air Force Magazine. “We’ve done it, and the evidence is that we have hit all our milestones to date. ... So far, our cost performance has been excellent.”

Hudson added that, at this stage of the program, all technical requirements are being achieved. The airplane’s mold line—its external shape—was frozen last fall, and the internal configuration design will be frozen soon. The JSF’s first flight-worthy engine, the Pratt & Whitney F135 power plant, already is being built. Plans call for first flight in fall 2005, with a Lot 1 production contract to take place a few months later.

Ten countries already share in the F-35 program, having contributed more than $4 billion to its development. Each is expected to buy the fighter, with defense analysts forecasting overseas sales of as many as 3,000.

Sprinting Toward Goal

As Hudson tells it, the F-35 is “sprinting” toward its principal goal: It will become the first fighter program to yield three distinct types of aircraft—a conventional takeoff version, a short takeoff and vertical landing type, and a carrier-worthy variant.

The Air Force conventional take-off version will be called the F-35A; the Marine Corps STOVL model the F-35B; and the naval carrier variant F-35C. All three types are to make inaugural flights in a single four-month period less than five years from project go-ahead.

The services will seek contracts covering a total of 163 airplanes by 2009. Initial operational capability is set for 2010 with the Marine Corps, 2011 with the Air Force, and 2012 with the Navy and UK forces.

Partially underwriting the $25 billion development effort are the program’s eight international partners. As a group, the partners have ponied up about $4.3 billion to have a role in the project. The United Kingdom, having kicked in $2 billion, is the largest contributor and the only Level 1 partner. This status allows London a voice in decisions regarding requirements and technology sharing. It also purchases the UK a place at the front of the queue for export sales.

At Level 2 are Italy, with a $1 billion contribution, and the Netherlands, with about $800 million. Neither country has yet committed to buying the JSF, but both contribute national know-how and receive some industrial benefits from their involvement.

Level 3 partners include Australia, Canada, Denmark, Norway, and Turkey, each of which has contributed $125 million to $150 million. None has committed to buying the airplane, but all are involved in technical issues and technology transfer.

It is assumed the partner countries—all of which have purchased the US–produced F-16, F/A-18, or AV-8B fighters—will buy some version of the airplane designed to succeed those three aircraft.

Foreign contributions go directly to the US government, not Lockheed Martin, the F-35 prime contractor. The agreements are on a country-to-country basis.
Nations at any of the three levels enjoy the official title of “partners.” DOD capped the number of international partners at eight last fall, but other countries that would like to purchase the airplane (or compete for a smaller work share) will be called “participants.” To date, the only two nations in this category are Israel and Singapore.

The partners have assigned representatives to the JSF program office, Hudson reported, and they do real work on managing development of the aircraft. The foreign representatives, said Hudson, are “absolutely superb people” who contribute not only management know-how but knowledge derived from projects such as the Eurofighter Typhoon.

Roughly the size of the F-16, the F-35 has a deeper fuselage for internal carriage of ordnance. It will also be just as agile as the Falcon but with more range. The F-35 will replace the F-16, A-10, older F/A-18s, and Marine AV-8Bs.

Harmonized Requirements

Hudson said the F-35, so far, has gotten “great support” from the military services that ended a prolonged period of programmatic horse-trading in the spring of 2000 by signing the joint operational requirements document for the fighter. The new document harmonized service requirements for speed, stealth, weapons payload, range, and other factors.

Doing away with shifting or competing requirements in the development phase has contributed to stability and reduction in cost.

“ Their requirements for those platforms have stayed absolutely steady since ... they were signed,” Hudson noted. He added that there have been no changes in threat that would require changing the document.

The F-35 development project—called SDD, for System Development and Demonstration—will yield 22 airframes. Fourteen will be flight-test articles, a mix of all three variants. The remaining eight airframes will be used for ground evaluations such as loads testing and component fit.

Though the F-35 program is moving at a brisk pace, the military services are already embroiled in internal debates over how the JSF will fit into their future force structures.

The largest number of new F-35s—about 1,700 of them—will go to the Air Force, which needs them to replace F-16s and A-10s in its current fleet.
The service is facing a possible conflict between its premier fighter program, the F/A-22 Raptor, and the F-35. Because USAF is planning to stretch out the F/A-22 buying plan, it will overlap with initial purchases of F-35s. (See “The F/A-22 Gets Back on Track,” March, p. 22.)

It’s a situation the Air Force would like to avoid. The service’s leaders prefer to stagger aircraft purchases to prevent budget spikes for fighter procurement in any given year.

Air Force Secretary James G. Roche, in an interview, said he doesn’t anticipate a problem. He explained that the typical pattern of fighter development programs will probably allow the shift to occur painlessly.
Roche, who had a full career in the Navy and then served as a top official in the aerospace industry, said his experience tells him the F-35 may not arrive on time.

“ I may, as a guy from industry, believe that the F-35 estimates today are optimistic,” Roche said.

Delays in the F-35, Roche observed, would allow the Air Force an extended buying period for the F/A-22 without causing the dreaded budgetary bow wave of two major programs running simultaneously.

However, the Air Force is not planning to tinker with its JSF plan just yet.

The X-35 STOVL demonstrator accomplished short takeoff, supersonic flight, and vertical landing all in one mission—hence the “hat trick” insignia on the tail.

No Pre-emptive Surrender

Roche said that Undersecretary of Defense Edward C. Aldridge Jr., DOD’s top acquisition official, is “quite right” not to engage in “pre-emptively surrendering” and simply assuming the F-35 will not meet its marks on time.
“ We’re going to stick to the program and let the program go” as currently structured, said Roche. However, he added, if the F-35 does arrive on time, the service would be willing to let the Marine Corps and Navy have their F-35s in larger amounts early in the program. They are in more urgent need of replacement aircraft, Roche asserted.

The JSF production line would be able to accommodate such changes, Hudson said. “Could we change the variant mix as it goes down the assembly line?” he asked. “Absolutely.”

He went on, “We’re going to build each variant on the same production line. This was one of the concepts we wanted to make sure we had taken care of, because we didn’t want to have three separate production lines, with three variants.”

Having the same production line—and using the same tooling—is possible because computer-aided design and manufacturing allows the tooling to change and adapt to the version coming along.

There are “some unique components that go into the STOVL jet,” Hudson hastened to add, meaning that a speed-up in the Marine/UK version would require a long-lead-time decision to have those parts ready when construction starts. Over all, however, the “family-of-airplanes concept makes it easier to make adjustments in the mix over time,” Hudson concluded.

Roche said the Air Force will not directly or indirectly do anything to upset the F-35 applecart. That is because USAF, under the unique JSF leadership-swapping arrangement between the Air Force and Navy, will be the service “in charge” during any alterations to the buying profile.

“ About the time this becomes a serious problem, guess who ‘owns’ the F-35?” asked Roche. “So, we have a vested interest [in seeing] that this is done right.”

A computer rendering shows the USAF production model. Inlets were moved aft to improve visibility for the pilot, and the overall airplane grew seven inches to permit room for growth in avionics.

When the JSF program manager is an Air Force officer, he reports to the Navy’s acquisition executive, and his deputy is a Navy or Marine officer. When he is succeeded by a naval officer, the Air Force acquisition executive assumes oversight of the program, and the deputy becomes a USAF officer.
The Navy, too, is reconsidering its buy of the JSF. As a result of a new streamlining effort that will merge Marine Corps and Navy squadrons, the services think their JSF requirement will decline as well.

“ We expect it will be in the 409–419 aircraft range, something like that,” a Navy budget official reported.

However, he quickly added that the consolidation will not affect the JSF program until it is well along—“well into the out-years” of the defense budget.
Plans call for first JSF procurement money to come from the Air Force in 2006, Marine Corps in 2007, and Navy in 2008.

Aldridge, asked about Navy plans and their impact on the program, said he expects there will be such overseas demand for F-35s that any reduction from the Navy’s air wing reorganization would be offset by international sales.

3,000 Fighters Needed

Government and industry experts forecast a requirement for as many as 3,000 F-35–class aircraft over the next 30 years. This is more than the number required by the US armed forces.

“ It wouldn’t surprise me that the services are looking at the production flow quite a bit,” said Tom Burbage, Lockheed Martin’s JSF program director. “It would not affect the SDD contract” if the Air Force or Navy opted to change their buy numbers, he said, because such changes would affect the production portion of the project, not development.

However, Burbage went on, “I think there’s a desire, at least on the part of [the Office of the Secretary of Defense] to keep the program as stable as they can.”
Hudson agreed.

“ We’re doing everything the same in development, regardless” of the final buy target, he said. “I have consistently said that if we perform well—if we do well on our cost and schedule performance and also our technical performance—that will help us keep great support, and, by keeping that support and keeping the stable funding, in turn we’ll be able to perform well.”
Burbage and Hudson noted that doing lots of groundwork in the concept definition phase helped speed things along in initial development and reduce risk. Even so, they said, serious technical challenges remain.

Though “no inventions ... have to happen,” said Burbage, some new technologies such as sensor fusion will be taken to a higher level, requiring unprecedented amounts of software. “We’ve got an excellent plan,” he asserted, but it’s too early in the program to gauge success.

The F-35C will fly from Nimitz–class aircraft carriers, as shown at top, as well as the CVN-X next-generation carrier. The Navy version will have larger wings and a beefier structure to sustain hard landings.

The Software Challenge

Hudson also cited software as the top challenge. He said there will be about six million lines of code in the airplane and another six million in the simulator, plus about three million in associated systems. While some of the 15 million lines of code can be lifted from other programs, the task is still “huge,” he said, and he is taking care to ensure that “we don’t underestimate the time and budget required to get the job done.”

Another challenge concerns “integrated subsystems,” Burbage noted.
He said, for example, that the JSF program wants to produce a single hardware item to provide auxiliary power, vapor cycling, and environmental control. This will save weight, because today’s aircraft have three separate devices.

“ There’s nothing unique about the requirements of the three machines,” said Burbage. “What’s unique is that we’re integrating them into one machine.” This is another area where “we’ve still got to prove” it can be done, he added.
Yet another challenge is the durability of the engine and the materials connected to it, such as the clutch and drive shaft for the STOVL version, he said.

Finally, Burbage said foreign customers will want to add their own requirements to the airplanes they buy, complicating the assembly process. The key will be to ensure that these demands are “not disruptive to the basic program.”

Hudson said the Pentagon will have to maintain “open architecture” for avionics. This means providing for the quick pace of electronics technology and leaving the system open to accept new and better hardware as it comes along, without suffering from the problem of disappearing vendors or equipment that becomes obsolete before the aircraft even flies.

The JSF is slated for several technology refreshes during development, specifically to head off avionics obsolescence. It was a key lesson learned from the F/A-22 program.

Another lesson stems from the tail buffet problem experienced by the F/A-22, the F/A-18, and other twin-tail designs, Hudson pointed out. The tail buffet problem—which led to an unexpected beefing up of the F/A-22’s tail—manifested itself just as the JSF was going through a structural analysis. It was “tremendously helpful” to have such forewarning, and what was learned from the vortex flow on the Raptor’s tail was applied to avoid the problem on the twin-tailed F-35.

“ We were early enough in the design cycle to take the lessons learned,” he said.

Other lessons include the complicated process of weapons separation from an internal bomb bay on a fighter, Hudson noted. “It’s something we absolutely have to do right on Joint Strike Fighter.”

All in all, having veterans of the F/A-22, F/A-18, and other projects in the program office has provided invaluable “corporate knowledge” for dealing with problems before they occur, Hudson remarked.

Hudson and Burbage noted that Pratt & Whitney has made progress in getting the F135 ready for flight. Prototype versions scarcely missed a beat during the concept demonstration flight-test phase—a performance unheard of in previous programs using a new engine.

Pratt’s F135 will be installed in the initial aircraft. Around the fifth production lot, General Electric’s F136 will be brought in as an alternative, and the two companies will compete for the annual buy.

In the “great engine war” of the 1980s and early 1990s, those two companies jousted to sell power plants for Air Force F-15s and F-16s. This time, however, the two engines for the JSF must be functionally identical. One will be interchangeable with the other in terms of software, repair tools, and its function in the airplane, even though they may be quite different internally. In previous competitions, aircraft could use only one type of engine, which required unique air inlets and other features to work properly.

The F-35 is designed to use either engine at any time. This practice will reduce the number of spare engines and parts that must be taken to forward operating areas. It will also lead to streamlined training, software updates, and support gear.

Both engines have to accommodate the JSF’s single-piece air inlet. There is no plan to enlarge the inlet should either engine house develop a more powerful variant of its power plant. The existing inlet can accept some growth in the generated power, Burbage said.

Since the selection of Lockheed Martin’s JSF design, the length of the aircraft has grown by about seven inches. This will allow growth in the number of systems that can be carried. More area was added to the verticals for increased stability. Weapons bay doors have been enlarged so the STOVL version can carry 2,000-pound-class weapons.

The F-35 will be able to fly with either the Pratt & Whitney F135 engine or General Electric F136 engine. The two power plants, though internally dissimilar, must be interchangeable in size, maintenance, and performance.

New Way of Building

The JSF will be assembled in a new way, too. Lockheed will build the front of the airplane in Fort Worth, Tex., and the plant will also perform final assembly. The midsection will be built by Northrop Grumman at Palmdale, Calif. The tail will be built at BAE Systems’ Samlesbury, UK, facilities.

The midsection and aft will come “stuffed,” Hudson said. That means they won’t be shells to fill with equipment but will have all the necessary equipment already installed when they arrive for final assembly.

It’s not accurate to say the three subassemblies will snap together, but the analogy isn’t too far off, Burbage said.

Wiring harnesses—developed in the Netherlands—will be in place in each section. At final assembly, they will be joined by connectors. The approach saves time by allowing pieces to be installed before being surrounded by other parts of the airplane and also saves weight and improves stealth by reducing the number of hatches and access panels.

Some members of Congress attacked the award of the F-35 contract to a single firm. They complained that the move would cripple the nation’s capability to develop future fighters competitively. They lobbied the Defense Department to insist that Boeing, loser to Lockheed in the JSF competition, be given some of the work. The Pentagon declined, leaving the contract as a winner-take-all but allowing Lockheed Martin the option of awarding work to Boeing if it wanted to.

Boeing wanted to be a “fourth strategic partner” on the F-35, Burbage said, but “there was no way to do that.” He said, “We already had the work spread across three prime contractors and across about 10 or 12 major subcontractors,” with Lockheed Martin itself only having a 19 percent share of the overall work. There simply wasn’t enough for another member.

“ The current team members invested heavily as a team, in a winner-take-all program, and it would have meant taking significant work share away from us or Northrop Grumman or BAE Systems to bring Boeing on.” Boeing will be allowed to bid on any remaining work not yet under contract, “as other people are allowed to bid,” Burbage said.

The JSF gets a lot of top-level attention, Hudson pointed out.

“ We have the service acquisition executives review this program every three or four months, ... and the service Secretaries and Mr. Aldridge, and the CEO–level folks from our contractors all get together about every five months and review this program,” he explained.

Additionally, there are committees of warfighter flag officers that review progress and relevancy of the program, a configuration steering board, an acquisition steering board, a committee on logistics and training, and other “high-level forums,” Hudson counted off.

“ This,” he said, “keeps a lot of bright lights on this program.”