Celebs cool their jets waiting for new Concorde to be built. (Media & Technology).

Tiger Woods, Paul McCartney, Claudia Schiffer and other jetsetters who zipped across the Atlantic in three hours on the Concorde may have to get used to more conventional travel for about the next decade.

Boeing Co. and Airbus SAS said it's likely to be at least that long before a supersonic successor to the Concorde is built.

The value of speed is so high for a select few, such as celebrities, sports stars and executives, that plane makers working on supersonic designs don't doubt a successor of some kind will be built. It probably will be a business jet, seating about 10 passengers, to surmount the technological hurdles of building a cost-efficient supersonic plane.

"Time is money and time is a lot of money for some people," said Keith McMullan, managing director of Aviation Economics, a consulting company.

Boeing, Airbus, Lockheed Martin Corp., France's Dassault Aviation SA and General Dynamics Corp.'s Gulfstream unit have all studied making a supersonic business jet. They concluded that a scheduled transport like the Concorde, which seats 100 and flies twice the speed of sound, isn't viable.

"The market right now is moving toward lower-seat mile costs," said John Leahy, chief commercial officer at Airbus, the successor company to the Concorde's builders. "The Concorde was one of the great engineering marvels of all time, but it was never an economic success."

Concorde alternatives

Air France has said four out of five Concorde seats were going empty. The plane burns twice as much fuel as a Boeing 747, costs three times as much to operate and falls short of modem noise standards.

Anticipating the end of the Concorde later this year, many plane makers stepped up research into supersonic technology in recent years. Boeing proposed a 225-seat "sonic cruiser" that would fly at close to the speed of sound, only to drop the idea when few airlines expressed interest.

Gulfstream and Lockheed Martin studied a business jet that would seat eight people and fly twice as fast as the $40 million Gulfstream V, cutting a typical New York-Paris trip to about four hours from eight hours.

Dassault proposed a similar plane. The company's chief executive, Charles Edelstenne, said last month that the company is still trying to make a viable business case and find an engine for the plane. He said Dassault is talking to several U.S. companies about working together on the project.

Turmoil in world economic markets and unresolved technological hurdles may leave planemakers reluctant to invest substantial sums for now. "There surely is a need for airplanes that are fast," said Pierre Rodocanachi, senior vice president at Booz-Allen & Hamilton Inc. in Paris. "But credible studies of the market can't be done before two years from now."

The war in Iraq, threats of terrorism, the outbreak of a killer respiratory disease in Asia and cuts in business spending have led to record airline losses. Business travel may not rebound until 2004 or later, according to a survey by the National Business Travel Association. Boeing, Airbus and other plane makers have all cut production.

"I would not expect any serious consideration of a supersonic airplane in the Boeing Co. for quite a while," said Todd Blecher, a company spokesman. "We couldn't close the business case."

Landing at rapid speed

One big obstacle is quieting the "sonic boom" of supersonic travel, said Gulfstream spokesman Robert Baugniet. The Concorde was limited to flying over water or at subsonic speeds over land. To be viable, a new supersonic business jet would have to be able to fly over the continental U.S., Baugniet said.

The U.S. Defense Advanced Research Projects Agency has awarded $35 million for Gulfstream, Lockheed and others to study ways to mitigate the boom. That's a fraction of the $3 billion to $4 billion that a supersonic business jet would cost to develop, said Richard Aboulafia, an analyst with the Teal Group, a consulting company in Virginia.

A supersonic business jet would also need to land at rapid speeds because of the shape of its wings, making it unsuitable for many smaller airports, said Philippe Jarry, chief of strategy at Airbus. An executive may not be able to reach many out-of-the-way places that he can in today's business jets, Jarry said.

"We have to humbly admit that the technology is simply not there," he said. "Not in this decade."

Aboulafia was less pessimistic.

At some point the market will rebound, and price is less of a concern when selling to jetsetters and top executives than it would be in marketing to airlines, he said. Some carriers could also develop their own services.

Deutsche Lufthansa AG, for example, now uses PrivatAir, a Geneva-based charter carrier, to offer business-class flights to the U.S. on two routes using Airbus A319s that seat 48 instead of 124 passengers. A similar service with high-speed planes could make sense, Aboulafia said.

Boeing's commercial-airplanes chief, Alan Mulally, has said the company might someday develop a high-speed business jet that could seat 15 to 30. "I'd be very surprised if civilians couldn't fly supersonic again by 2020," Aboulafia said. "Until then, of course, you can do that by getting into the back of an F-16."