Tailless fighters, reusable space vehicles, blended wing body transports and hypersonic strike missiles are just some of the technologies on the drawing board at Boeing's Phantom Works

Graham Warwick/WASHINGTON DC

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Boeing's Phantom Works appears increasingly aptly named as it becomes a "virtual" organisation linking the aerospace giant's advanced development centres.

Despite inviting comparisons with Lockheed Martin's renowned Skunk Works, Boeing has adopted a different approach, establishing a Phantom Works presence at all its major manufacturing sites and creating an enterprise-wide research and development organisation. Lockheed Martin, meanwhile, has elected to keep the Skunk Works as a standalone operation.

Begun as a rapid prototyping operation within McDonnell Douglas' St Louis fighter plant - home of the famed F-4 Phantom, after which the unit is named - the Phantom Works expanded to encompass the advanced development activities of the company's helicopter, missile, transport aircraft and space divisions.

Following the merger with Boeing in 1997, the unit's charter expanded again, to include the R&D operations of the heritage Boeing and Rockwell businesses. By the end of this year, the Phantom Works will have operations in all three of Boeing's groups - Aircraft and Missiles, Commercial Aircraft and Space and Communications.

"Phantom Works was justwithin Aircraft and Missiles; now it's across the entire enterprise," says general manager George Muellner. "We have three main activities: to co-ordinate R&D in Boeing to minimise duplication and maximise application; to pervade best practices and technologies throughout Boeing; and to put together 'system of systems' solutions that bring together different groups."

David Swain, executive vice-president of the Phantom Works, says: "Our role is to support each operating group, and to provide technology and advanced product help to improve their business performance in the near, mid- and long term." Across Boeing, the unit's activities range from validating design processes to building technology demonstrators.

"Near term, the Phantom Works can transition technology to improve the affordability of current products," says Swain. "Mid-term, it can validate processes for use in the design and development of future products. Long term, it can look for products that cut across or fall between the groups."

It is important to win start-up programmes that are five to 10 years away from engineering and manufacturing development, says Swain. "That way, we can start to work with the customer and start to apply new processes."

In this respect, the Phantom Works has been remarkably successful. In recent years, the organisation has won several advanced technology demonstration contracts awarded by the USDefense Advanced Research Agency (DARPA), NASA and the USAir Force. More often than not, these are cost-sharing contracts, with Boeing contributing up to half the total funding. They include:

• X-36 - a NASA/USAF demonstration of technology for an agile tailless fighter and for reconfigurable flight controls;

• X-37 Future-X Pathfinder - a NASA/USAF programme to demonstrate a reusable space vehicle that can operate in orbit, re-enter and land autonomously;

• Unmanned Combat Air Vehicle (UCAV) - a DARPA/USAF effort to demonstrate suppression of enemy air defences (SEAD) using unmanned strike aircraft;

• Dragonfly - a DARPA-led flight demonstration of Boeing's Canard Rotor/Wing (CRW) vertical take-off and landing (VTOL) concept;

Affordable Rapid Response Missile Demonstrator (ARRMD) - a DARPA programme to design low-cost hypersonic strike missiles;

Solar Orbit Transfer Vehicle (SOTV) - a USAF-sponsored demonstration of a solar-powered spacecraft able to deliver payloads to higher orbits at low cost.

The Phantom Works is also engaged in several internally funded programmes, including studies of the Blended Wing Body (BWB) ultra-large transport aircraft and the ultra-short take-off and landing Advanced Theatre Transport (ATT). The advanced development unit is also responsible for final assembly of Boeing's two X-32 Joint Strike Fighter (JSF) concept demonstrator aircraft.

Increasingly, the Phantom Works is bidding for, and winning, programmes that involve several of the company's manufacturing sites. Key recent wins are the X-37 and UCAV programmes, which bring together elements of the heritage of Boeing, McDonnell Douglas and Rockwell. "We bring people located at the different manufacturing sites together on major programmes," says Swain. "They have different perspectives, backgrounds and product domains, so we get the best of Boeing."

Another reason for this approach is to spread knowledge of new processes and technologies throughout the company as quickly as possible. People who worked on the successful X-36 programme, for example, are now engaged in the CR/W and UCAV efforts. Although the X-36 was a St Louis product, the new programmes are run out of Mesa and Seattle, respectively.

"We put the centre of gravity [of a major programme] as close as we can to the operating group manufacturing the product," says Swain. "We bring the operating group the latest technology - they provide the detailed domain knowledge." The UCAV programme, for example, is run out of Seattle because of that site's experience with complex command and control systems.

"Generally, we bring people together virtually," says Swain. "It works better than anticipated. The most effective tools are e-mail and conference calls with PC connections." Real-time video links are being used with good effect on the JSF programme, allowing designers in Seattle to "walk round" the aircraft in final assembly at Palmdale, California.

The links become complicated when it comes to programmes like the X-37, which involves several Boeing sites in southern California as well as the Phantom Works plant in St Louis. But the programme is viewed as a testbed for sharing research and transferring technology, and the potential payoffs from the synergies are expected to be high.

The four-year, $173 million programme is funded roughly equally by Boeing and the US Government. The X-37 will be the first X-plane in orbit and will demonstrate technology for low-cost access to space. After release from the Space Shuttle payload bay, the vehicle will be capable of autonomous operation in orbit, through re-entry to a runway landing.

The vehicle is a 20% scaled-up derivative of the X-40 Space Manoeuvre Vehicle (SMV) technology demonstrator built by the Phantom Works for the USAF. The unpowered X-40 was drop-tested from a helicopter last year to validate its autonomous approach and landing capability. The X-40 itself is a 90% scale model of a small reusable spacecraft capable of functioning as a satellite bus or upper stage.

Several X-37 technologies have already been tested in the X-40, including autonomous approach and landing guidance using a differential global positioning system and air data calculation using a global positioning/inertial navigation system. Further X-40 drop tests with improved flight control algorithms are planned for next year. They will be precursors to X-37 drop tests planned for 2001.

Orbital flights

Two orbital flights are planned for late 2002, one lasting a few days and one up to three weeks, both ending with "aggressive" re-entry flight profiles at speeds up to Mach 25 and autonomous runway landings at either Edwards AFB or Vandenberg AFB in California.

The X-37 will be assembled at Palmdale. The modular airframe will be composite, with carbon silicon carbide wing and tail skins and reusable thermal protection blankets and tiles. The 7,000lb-thrust(31kN) Rocketdyne AR2-3 engine will use storable hydrogen peroxide and kerosene propellants.

Boeing sees a reusable spaceplane derived from the X-37 as a viable option for replacing its Delta IV launcher after 2010, as the upper stage of either an expendable or reusable, DC-XA-type, two-stage-to-orbit vehicle.

The UCAV programme, meanwhile, will bring together Phantom Works sites in Seattle and St Louis with locations in Mesa and southern California. Under the $131 million cost-share effort, Boeing will build two air vehicles and a reconfigurable mission control station to demonstrate the technical feasibility, operational capabilities and affordability benefits of integrating UCAVs into manned air combat operations.

"UCAVs represent a revolutionary new weapon system that can significantly increase the effectiveness and survivability of manned fighter aircraft while lowering the overall cost of combat operations," says Swain. Demonstrat-ing their feasibility will require the Phantom Works to draw on Boeing's experience with manned strike aircraft, weapon systems, unmanned air vehicles (UAVs) and C4ISR (command, control, communications, computers, intelligence, surveillance and reconnaissance) technology, he says.

"The key challenge is not to go out and fly," says Muellner. "It is whether you can have an unmanned vehicle that can kill. The UCAV has to be interoperable with manned aircraft and ground forces, and that means a system of systems solution."

Muellner says the Boeing team will draw from several other PhantomWorks programmes. These include simulation and modelling techniques developed for the JSF; the Small Bomb System, a 113kg (250lb) precision-guided weapon; the Rotorcraft Pilot's Associate decision-aiding system; tailless thrust vectoring and reconfigurable flight controls from the X-36; and landing and recovery techniques from the DarkStar UAV programme.

The USAF sees UCAVs augmenting the manned aircraft force structure after 2010 for high-risk, high-priority missions in which success and survivability are key. The first role planned for such vehicles is suppression of enemy air defences ahead of manned aircraft. UCAVs are also expected to have lower acquisition, operation and support costs. The "fairly stressing" targets, says Muellner, are for an acquisition cost one-third that of a low-end fighter today, and an 80% lower operating cost.

Tailless design

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Boeing's design for the full-scale UCAV demonstrator draws heavily on the X-36. It is a tailless aircraft 8.2m (27ft) long with a 10.3m wingspan and 3,600kg empty weight. The air vehicle is powered by a 6,500lb thrust-class AlliedSignal F124 non-afterburning turbofan. Line-of-site and satellite links will be required to maintain communication with the UCAV from the ground or other aircraft.

A key concept to be demonstrated by the DARPA-led programme is that of "variable autonomy", which will allow the vehicle to make its own decisions depending on the phase of flight while ensuring that any lethal action remains under human control. End-to-end demonstration of the UCAV concept, including interoperability with manned aircraft and weapon release, is planned for 2002.

By then, Boeing plans to have flown another unusual demonstrator. Under a 37-month, $37 million 50:50 cost-share agreement with DARPA, the Phantom Works is building two subscale, unmanned technology demonstrators to validate the CRW advanced rotorcraft concept. The effort is being led by Boeing Mesa, where the demonstrators will be assembled, and involves Philadelphia and St Louis sites.

Boeing says the CRW combines the speed of a fixed-wing aircraft with the flexibility of rotary-wing flight. The aircraft takes off and lands like a helicopter, using a two-bladed reaction-drive rotor powered by exhaust gas diverted from the turbofan engine. For forward flight at speeds exceeding 375kt (695km/h), the rotor is stopped and locked in place, becoming a wing, and the exhaust is diverted aft to a jet thrust nozzle.

Reaction drive eliminates the need for a mechanical gear train and anti-torque system, reducing weight, complexity and cost, says the company. Transition between fixed-wing aircraft and helicopter modes would occur at between 90kt and 120kt, taking "seconds".

The two CRW demonstrators will be 590kg vehicles, appropriately sized to meet DARPA's requirement to demonstrate the concept's suitability as a VTOLUAV. This also allows the PhantomWorks to reuse assets, including the 1,270lb-thrust Williams International turbofan from the X-36 programme. Windtunnel tests are under way, as are ground tests of the gas path, and flight tests are planned for 2001.

Boeing has studied growth versions of the CRW ranging from a 1,100kg maritime VTOL UAV to a 10,000-11,000kg manned aircraft, suitable for use as an armed escort fighter to accompany the V-22 tiltrotor transport.

Demonstrating the breadth of Phantom Works activities is the 18-month, $10 million AARMD contract to study an affordable hypersonic strike missile. This involves sites at Seal Beach, California, and Duluth, Georgia, as well as St Louis. Two missile concepts are being pursued, each capable of speeds exceeding M6, but with an average flyaway price of only $200,000.

The ARRMD is intended for launch from aircraft, surface ships and submarines against mobile missile launchers and buried command centres, with a time to target of less than 7min from a stand-off range of more than 650km (400 miles). One design is a "waverider" powered by a Pratt & Whitney supersonic-combustion ramjet (scramjet). The other has a more conventional cylindrical shape and an Aerojet dual-combustion ram/scramjet.

Affordability objectives

If performance and affordability objectives can be demonstrated, DARPA plans to proceed into a 30-month demonstration programme for one or both of the concepts. Boeing believes a hypersonic strike missile could be operational as early as 2010.

At the other end of the speed scale is the SOTV, which will use a Rocketdyne-designed solar thermal propulsion engine to move satellites into geostationary orbit (GEO) with twice the efficiency of chemical stages. The trip will take 20-30 days because of the engine's relatively low thrust, but once there, the SOTV will provide electrical power for the satellite for up to seven years.

Under a $48 million USAF contract, the Phantom Works is planning a subscale, autonomous on-orbit demonstration of the bimodal solar thermal propulsion and power concept for late 2001 or early 2002.

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In addition to these programmes, the Phantom Works is looking for funding to fly subscale unmanned ATT and BWB demonstrators around 2001. The ATT (above) is a tilt-wing concept built around the C-17 fuselage with the ability to lift a 32,000kg payload from a 230m (755ft) airstrip. The BWB is a large flying wing with integrated engines that offers aerodynamic and structural benefits. Boeing has yet to decide whether to proceed with either of these projects beyond the study stage.

Many of the technologies under development at the Phantom Works, including open-system avionics, survivable flight controls, phased-array antennas and advanced manufacturing processes, apply equally to Boeing's commercial and military products. "We get good migration of technology from commercial to military," says Muellner.

The gap between aircraft and space programmes is also closing. "We are finding more and more that the technologies are merging," says Swain. With R&D investment in aircraft essentially flat, and that in space increasing, sharing technology effectively is becoming essential, says Boeing.

Swain sums up: "The Phantom Works' job is to be a conduit that cuts across the operating elements. We demonstrate the future in everybody's back yard."

Source: Flight International