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New York to L.A. in Two Hours
A new generation of supersonic private jets could trigger a boom in luxury high-speed flight -- without the sonic boom normally associated with breaking the sound barrier.
Lockheed Martins advanced Skunk Works unit is designing a small, 12-seat passenger jet that would travel at 1,200 mph (Mach 1.8) but which would produce only a whisper of the annoying crack once emitted by the retired Concorde.
The sleek, 130-foot-long QSST (for "quiet supersonic travel") aircraft is being designed for a Nevada consortium called Supersonic Aerospace International, or SAI, at an estimated cost of 2.5 billion.
Aimed at business executives and diplomats, the QSST will fly at nearly twice the speed of conventional business jets and have a range of 4,600 miles nonstop -- Los Angeles to New York in just over two hours.
It could be ready for boarding by 2013, according to the company.
"Our design uses innovative aerodynamic shaping and employs a patented inverted V-tail that is instrumental to the radical reduction in sonic boom," said Frank Cappuccio, Skunk Works executive vice president.
Designers expect the QSST to make a sonic boom less than a hundredth that of the Concordes aural impact. Concorde was barred from flying at supersonic speeds over the United States when it debuted in the 1970s because excessive noise was produced by pressure waves colliding in the planes wake.
Now, using modern computer-aided design software to model quieter "boom reshaping" techniques pioneered by military test fighters, SAI hopes to use a smaller craft to fill a gap left by the collapse of the Concordes service following a fatal 2003 crash in Paris.
SAI revealed new details to aerospace analysts at the Farnborough International Airshow in England last month, claiming to have received interest in creating a scheduled supersonic service linking the worlds financial centers.
But QSST is not the only group scrambling to create a superfast executive commuter network.
Rival Aerion, also of Nevada, is designing a slower 12-seat supersonic business jet, or SSBJ, that would reduce aerodynamic drag using straight, natural laminar flow wings.
The SSBJ would produce a quieter, Mach-1.6 boom over water and fly at near-supersonic speeds over land. The wings will be tested at Albuquerque, New Mexico, this month.
Both companies have identified a market for up to 300 jets in little over a decade, each craft costing around 80 million, and are looking for investors and development consortia.
But engineers will have to carefully navigate laws restricting overland supersonic flight if they
e ever to take off, said Bill Dane, senior aviation analyst with aerospace research firm Forecast International.
"The two major obstacles are available engines and the need to significantly reduce or to outright eliminate the sonic boom phenomena," he told Wired News. "If such an aircraft is to be a commercial success, it will have to fly over land and not just oceans."
Dane said there also needs to be an international set of rules regarding the noise issue.
"Several company spokespersons have said flat out that they do not want to invest millions or more in SSBJ research only to find that the aircraft cannot be operated in some regions or countries," he said.
Dane added that teams in France, Italy and Russia are also pursuing supersonic passenger jet designs. Delaying half the sonic waves so they do not reach the ground at the same time and create the unwelcome boom is one concept being explored, he said.
Some of the designs look into a crystal ball and assume the laws prohibiting sonic booms from civilian aircraft, first introduced in 1968, will be redrafted to take account of newer, quieter technologies.
"Over the next several years, regulations for low sonic boom will be developed and low-boom technology will be improved," says Aerions promotional material. "Aerion will then develop low-boom aircraft to operate under the new regulations."