The beak-nosed, supersonic Concorde was once described by a British ambassador as the "flower of the aerospace industry."

But while the sleek plane could cut travel times in half, it was ultimately doomed by a combination of high maintenance expenses, a slower market for air travel after the Sept. 11 attacks and high ticket prices. A round-trip flight from London to New York could cost as much as $18,260 in today's dollars.

Now, almost 14 years after the Concorde's last flight, a handful of companies and entrepreneurs are betting that technological advances in materials and computing, as well as the boom in global business travel, could power a resurgence in economically viable supersonic passenger jets.

"We're benefiting from 50 years of progress in fundamental aerospace technology," said Blake Scholl, chief executive of Boom Technology Inc., a Centennial, Colo. start-up that's aiming to build a supersonic airliner called the Boom. "Since the Concorde was developed, the amount of international business and international travel has skyrocketed. You can find a huge market."