Next-Generation Air-Mobility Concepts Focus on Efficiency.

In anticipation of future investments by the U.S. Air Force in air-transport and in-flight refueling aircraft, aerospace giants Boeing Co. and Lockheed Martin Corp. are pushing their own air-mobility platform concepts, hoping that their ideas will result in long-term business opportunities.

The notion of a single platform--that would serve both as a transport and as a refueling tanker--underpins some of the ongoing work by design engineers at Lockheed Martin Aeronautics Co., in Marietta, Ga.

"We used to think of airlift as an end in itself," said Edwin E. Tenoso, the company's director of customer requirements. "I think we should think of airlift as part of the transportation system," he said during a Defense Week conference on military airlift in Washington, D.C. For that reason, he explained, tankers should not just be used for refueling, but also as a cargo-carrying platform. The Air Force KC-10 is an example of a dual-capable aircraft.

When planning for the future, the Air Force should not think about a new cargo plane or a new ranker, separately, but should focus on a large "mobility" aircraft that can serve as either, Tenoso said. "The Air Force should challenge those of us in industry to solve the mobility problem, not just a tanker problem.

"Should the Air Force be interested in a large mobility aircraft, we would be willing to engage in serious discussions," he said. So far, "the Air Force has not stated a requirement. When they do, we'll be ready to make a proposal."

Lockheed's concept is for a so-called advanced mobility aircraft, a multi-boom tanker/transport. That aircraft would be suitable as a KC-135 tanker replacement, and also could supplement the C-5 and the C-17 heavy transports.

"We have looked at several different types of large mobility aircraft," Tenoso said. The most promising so far, he said, is a concept for a tail-less aircraft called the "box-wing." As its name indicates, the box-wing is a diamond-shaped rigid structure, with two wingtip booms or drogues for in-flight refueling. This aircraft would be able to carry 200,000 pounds of cargo.

It would be about the same size of a KC-135, maybe slightly bigger, Teneso said. "[But] you could drive it into the KC-135 hangar."

The box-wing is a paper-only concept, but Tenoso said a model has been built and flown in a wind tunnel.

The box-wing, additionally, could serve as a strategic platform--as a command and control post or as a ground surveillance system. Tenoso believes the Air Force could use the box-wing airplane as a command platform to remotely control various unmanned aircraft.

A price tag for the box-wing has not been estimated, he said. "We haven't worked through the cost." He believes that, if the Air Force planned a large buy, it would help spread the development costs over many aircraft.

Andy Bennett, manager of air mobility systems at Lockheed Martin, said the box-wing could be built as a stand-alone transport or tanker, or it could be a dual-mode configuration. The multiple booms available in the box-wing offer a significant improvement, Bennett said in an interview.

"The intent is to have more booms in the sky ... do more missions with fewer tankers. But the most important thing is that you can refuel multiple aircraft in a shorter period of time." It could be designed to land on short airstrips.

Even though the box-wing concept appears futuristic, said Bennett, it could be built with conventional technology. "We could build one today."

But, given the Air Force budget plans, Lockheed Martin would not expect to be producing a new aircraft for at least 15-30 years, he said. The KC-135 would need to be replaced sometime between 2013 and 2040.

Besides working on advanced aircraft concepts for the Air Force, Bennett also has been involved in a Navy project to make the C-130 tactical transport water-capable.

The idea was to enable the C-130 to land in water and take off from water. "It's not a huge technological challenge," he said. The problem is not the technology but the lack of qualified aerospace engineers. "The people who know how to design that type of hull shape are rapidly disappearing," he said. "Sea-planes were last built in the 1960s so the technology base is shrinking fast."

In addition to the box-wing, Lockheed Martin developed another large cargo aircraft concept, based on commercial technology for structures and aerodynamics, said Bennett.

The company also is working on a so-called blended-wing body configuration, which looks like a flying wing. "It would have a shorter and wider fuselage," Bennett explained. The blended-wing aircraft would be capable of carrying 54-foot containers, like the ones used on ships.

Air Force Gen. Charles T. Robertson Jr., chief of the U.S. Transportation Command, believes that a multi-mission, ranker/transport aircraft, in principle, is "a good idea."

But he cautioned that "the requirements in almost every scenario are going to be simultaneous, Like [with the] KC-10s, you can't assume you can always use them as a tanker. And you can't assume it's an airlifter [only] either."

Robertson would support the concept of a multi-mission aircraft, "as long as it doesn't drive the cost too high because you try to do too many things, and as long as you don't double count." That means nor assuming that they can be used as cargo planes and as a rankers at the same time, in two different parts of the world.

The Boeing Co., meanwhile, is banking on the success of a commercial version of the C-17, called the BC-17X. Several years ago, it was known as the MD-17.

Sales of this aircraft would not only help keep the Long Beach, Calif.-based production line open beyond 2004, but also could indirectly make more of these planes available to the Air Force, via the Civil Reserve Air Fleet (CRAF) program, said Boeing officials. Approximately half of the Air Force's airlift requirements are fulfilled by CRAF.

The Air Force and Boeing recently unveiled a plan to encourage private cargo carriers and airlines to purchase the BC-17X. "The idea would be to have more BC-l7Xs available from commercial carriers for military use under the CRAF," said Boeing spokesman Rick Sanford.

No BC-17Xs have been sold yet, he said.

Under the CRAF program, airlines and air-freight service firms contractually pledge aircraft to the Air Force, which would request their use for national emergencies. To provide incentives for civil carriers to commit these aircraft, the Air Force generally awards peacetime airlift contracts to civilian airlines that offer aircraft to the CRAF.

The so-called international airlift services contract is the largest of these. For fiscal 1999, for example, the guaranteed portion of the contract was $345 million, in addition to more than $300 million of business that was not guaranteed.

To join CRAF, carriers must have U.S.-registered aircraft capable of over-water operations, at least 3,500 nautical mile range, and 10 hours per day utilization rate. Carriers must also commit and maintain at least four complete crews for each aircraft. As of January 2000, 34 carriers and 729 aircraft were enrolled in the CRAF.

The Air Force unveiled a proposal in mid-December, recommending that Boeing build the BC-17X under the assumption that those aircraft would be used in times of war, under the CRAF program. Preliminary plans indicate that Boeing would build 14 BC-17Xs beginning in 2004.

John Sams, director of product support at Boeing, said the BC-17X would target a niche market that currently is filled by the Ukraine's AN-124.

"Our research shows that there is a marker that can support this," said Sanford. A BC-17X would cost under $200 million.

It would be quite similar to the military C-17, except that it would not carry ranks, but Caterpillar tractors to airstrips near construction sites, he explained. "They do not require runways."

A BC-17X, unlike the C-17, would not be allowed to airdrop cargo or people. And it cannot be refueled in flight.

"We see a global market but also a strong domestic market," said Sanford. The engines flown into Boeing's Seattle factory come in AN-124 airplanes. "We would rather have our own airplanes fly in the engines."

As a tanker replacement for the KC-135, Boeing currently is marketing a variant of its commercial 767 jet.