FRANCE. As Concorde soars into its 10th year, designers dream of faster things

On its 10th birthday, Concorde is flying high. After years of losses, the world's only supersonic passenger jet is finally profitable. And its French and British designers are dreaming of bigger exploits, a ``hypersonic'' plane that would fly even higher and faster.

The optimism is a bit relative. When it was conceived in 1962, Concorde was supposed to revolutionize air travel. Instead, it almost sunk financially both the British and French aereonautic industries, costing a total of nearly $7 billion.

Concorde's supporters argue that the plane should not be judged in cut-and-dry economic terms. For one thing, they say, it brought the technological knowhow that made it possible to develop another commerical aircraft, the profitable French Airbus.

They also say that Concorde helped bolster both countries' high-tech images, counteracting the traditional notion of Britain as a declining industrial power and of France as a producer of only luxary products such as designer fashions and foie gras.

``It gave us credibility,'' argued Paul Gauthier, one of the plane's creators, at the birthday celebration. ``It showed that France and Great Britain were capable of creating a plane that neither the Americans nor the Soviets could achieve.''

But even Gauthier admits that Concorde never achieved its original optimistic goals. The plane consumed exorbitant amounts of fuel, appearing on the market at a time when oil prices were soaring. Ticket prices were also extremely steep.

Only 18 planes were built before the production run was stopped. All were bought either by Air France or British Airways.

Both companies originally tried to use the plane on runs to multiple destinations around the world. That attempt incurred huge losses.

Now Air France limits its seven Concordes to the North American route, running 11 flights a week from Paris to New York. Two of those flights continue to Washington, and another two to Mexico City.

The service is making money. A one-way ticket to New York costs 14,315 francs, almost $2,000. Businessmen are willing to pay the sum, however, because the plane leaves Paris at 11 a.m. Paris time and arrives in New York at 8:45 a.m. New York time, allowing a full day of work. Last year Air France officials said Concorde had earned 36 million francs, slightly more than $5 million.

British Airways benefits from a similar strategy. Its 11 Concordes are operated on a regular schedule between London and New York. British Airways also has found that it can profitably charter the plane to groups for special excursions.

How about a one-day tour leaving London to visit Egypt's Pyramids? Concorde is the only passenger plane in the world that can do it.

However, Concorde's legacy might not be the ultimate expense account vacation or the ultimate in exotic travel. It could be a new generation of airlines.

Partly because of the experience with Concorde, the European aerospace industry has prospered during the last decade. Airbus conventional passenger jets are selling well, offering American airplanes their toughest competition, and the European space program has produced the successful Arianne rocket.

Now the Europeans are talking about their own space shuttle, dubbed Hermes. Along with it may come a type of ``hypersonic'' jet that would rocket into the stratosphere and descend on the other side of the planet. Sydney, Australia, could be reached from London in one hour. A dream?

``Not at all,'' replied Gauthier. ``After Concorde, I believe no technical problem is insurmountable. It's only a question of political will.''