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
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 tanker, 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
“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
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
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
Air Force Gen. Charles T. Robertson Jr., chief of the U.S. Transportation
Command, believes that a multi-mission, tanker/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 not assuming that they can be used as cargo
planes and as a tankers 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
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-17Xs available from commercial carriers
for military use under the CRAF,” said Boeing spokesman Rick
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
“Our research shows that there is a market 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 tanks, 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.