Lockheed Martin's Skunk Works is leading a project to develop
a supersonic business jet (SSBJ), funded by an unidentified customer.
It uses patented technology to suppress the sonic boom, so that
the new SSBJ could fly at supersonic speeds overland. Some 50 engineers
are working behind code-locked doors on the project.
According to program manager Tom Hartmann, Lockheed Martin's secret
project has been under way since 2001, and wind-tunnel tests and
computer studies have shown that a low-boom jet is technically feasible.
Now, Lockheed Martin engineers-supported by powerplant specialists
at Rolls-Royce, General Electric and Pratt & Whitney-are working
to define how much time and money it will take to complete the project.
One key issue is whether it will be necessary to build a near-full-scale
demonstrator in order to convince government regulators that low-boom
supersonic flight overland is acceptable.
Hartmann won't be drawn on an exact timeline for the project and is even more
careful about information pointing to Lockheed Martin's backer.
However, a number of indicators point to NetJets owner Warren Buffett.
Lockheed Martin first broached the idea of a low-boom supersonic
jet, in collaboration with Gulfstream in 1998-99. Micky Blackwell
(then leader of the company's aeronautics group) asked NASA administrator
Dan Goldin to back the project-and was joined at that meeting by
an unnamed customer, believed to have been Buffett.
Since then, NetJets leaders have repeatedly expressed enthusiasm
for a supersonic project-and Buffett could bankroll the entire program
and still not lose his second-place standing on the Forbes 400 list
of America's richest individuals. Show News was politely informed
by a representative of Buffett's Berkshire Hathaway company that
the Oracle of Omaha is not giving interviews, on this or any other
subject.
The potential payoff is enormous. The October 2002 issue of Lockheed
Martin's Aerostar company newspaper reported an award to Hartmann,
saying that he was "Instrumental in launching a major, highly
sensitive program, which could result in the design, development,
certification and production of 300-500 flight vehicles."
(This issue has vanished from the company's website.) In addition
to the corporate jet market, the SSBJ could be used for intercontinental
fast-package services and military missions.
Low-boom technology received a major boost on August 27, when
Northrop Grumman carried out what seems to have been a very successful
test under the Defense Advanced Research Project Agency (DARPA)
Shaped Sonic Boom Demonstration (SSBD) project. (SSBD is part
of DARPA's military-oriented Quiet Supersonic Platform effort
and Lockheed Martin has access to SSBD data.) An F-5E fighter
with a bulbous, recontoured forward fuselage made a supersonic
run near Edwards AFB, followed minutes later by an unmodified
F-5E at the same speed on the same flightpath.
Ground and air measurements showed that the differences between
the two booms were very close to computer projections. This is
vital: no wind tunnel can reproduce the behavior of a shock wave
as it expands away from the airplane, so anyone seeking to design
a low-boom aircraft has to place a great deal of trust in the
computers.
Patent drawings show that Lockheed Martin is not looking for a
single magic-bullet solution to the boom problem. Instead, the
company is using a series of shaping measures-an annular fairing
around the nose, gull-shaped wings and boom-canceling shrouds
around the engines-to reduce boom impact on the ground.
Many of the low-boom features used by Northrop Grumman and Lockheed
Martin correspond to theoretical studies by Dr. Richard Seebass,
a professor at the University of Colorado. Seebass-who died in
2000-started looking at low-boom designs in the early 1970s, but
until the mid-1990s not even the most powerful CFD codes could
model the phenomena that Seebass described. Seebass, says Hartmann
today, "will be the Wilbur and Orville of low-boom."
Lockheed Martin is not the only player in the SSBJ game. Boeing
Business Jet leaders and other senior Boeing executives have said
on several occasions that an SSBJ could be a reality by 2010.
Newly released patents show that Boeing's Sonic Cruiser Mach 0.98
airliner project, shelved late last year, was one member of a
family of airplanes that would have included an SSBJ, and that
clearly reflected the influence of Sukhoi's supersonic cruise
designs.
Sukhoi itself has formed a technology partnership with Dassault,
with SSBJs as one of its topics. Dassault-which announced an SSBJ
project in 1997, but later shelved it for want of a suitable engine-still
has an SSBJ study team in place.
Gulfstream, which has maintained an SSBJ design team since ending its relationship
with Lockheed Martin in 2000, has also continued to evolve its designs,
aiming at a 4,000 nmi-range airplane with a Gulfstream II-size cabin.
The company's latest design concepts feature a swing-wing (like
Boeing's supersonic transport designs in the 1960s) in order to
reconcile supersonic efficiency with the ability to use the same
6,000-foot runways as Gulfstream's subsonic jets.
