Difficult birth - and death - of a national emblem

Concorde was, and is, much more than an aircraft. It's an emblem. Alan Bond, an aeronautical engineer who has for years laboured to develop a successor, sees it as Britain and France's equivalent of the space programme.

"It wasn't as large an expense [as the Apollo project], but technically it was as large a challenge," says Bond, who runs Reaction Engines, a company that is working jointly with an Italian team on a "spaceplane". So far his project remains mostly on the drawing board - as did Concorde until about 1956.

In fact, one can track the delta-winged plane's genesis back to the specification issued in 1943, when the British government sought designs for an experimental aircraft able to fly at one and a half times the speed of sound. Although the design, codenamed "Miles M.52", was dropped near its completion in 1946, it sparked an idea which grew, by 1956, into the Supersonic Transport Aircraft Committee.

France turned out to be thinking in the same way, and the government's desire to get Britain into Europe - and not to waste money when bills could be shared - led, on 29 November 1962, to a treaty of cooperation between the two countries. One thing the British overlooked in their eagerness, however, was a no-cancellation clause inserted by the French. But, with the development cost estimated at only £200m (about £2bn in today's figures), who would want to cancel it?

Then the rubber met the runway, and the problems started. The trouble with Concorde was the trouble with any supersonic aircraft: it's enormously difficult to go that fast. The faster you go, the more air resistance builds up in front of the plane, making the process less and less efficient. Breaking the sound barrier helps - but Concorde has to fly at twice the altitude of normal commercial aircraft because it simply cannot make headway at a lower one.

Then there was the problem of the heating of the metal skin at high speeds (so that the plane actually expands and shrinks during its journey); and the difficulty of making an aircraft that was both an efficient subsonic plane - for takeoff and landing - and supersonic. .

A couple of years after the treaty was signed, the young, thrusting minister of technology in Harold Wilson's new "white heat of technology" government noted that it was the biggest aircraft project in the world: "If it succeeds," he said, "then in one single aircraft the development work of the last 50 years will have doubled in efficiency."

However, Tony Benn - for it was he - now notes that in fact, Labour wanted to cancel the project when it came to power in 1964, worried about the spiralling costs. But the French had pointed to that inconvenient clause...

The costs went up, to £700m, even as Benn talked up the prospects of selling "200, 400" Concordes to foreign airlines.

When he returned to government in 1974, the Treasury was still trying to kill the project: "I had the job of trying to save it." But he thinks that it "has been a success". Though only, one would think, if you enjoy Pyrrhic victories. All the airlines in Europe, North and South America and the Far East, which had earlier had options on aircraft, dropped out. Only British Airways and Air France bought them, getting them for a song.

For, in the US, Boeing was implementing its new airframe. "I think you could say that the difference was the British attitude, which I'm afraid is still prevalent, about such things being for the privileged classes," says Bond, "while the Americans thought about doing it for everyone." The result: the 747 "Jumbo jet" was designed to carry hundreds of people; Concorde, about 120. Concorde's travelling range was also limited - because of its fuel consumption, getting across the Atlantic was the best it could manage.

But the engineers laboured, and Concorde, for all its problems, was born. Like all great designs, it looks obvious and elegant from a distance. Close up, you discover that every minor angle and curve, the finely judged camber of the wing, the degree to which the delta tapers to the back, is the result of extensive testing. Nothing about Concorde is guesswork.

But that is also its curse. The avionics on board are still those of the 1960s; it is reckoned that they cost seven times more to maintain than modern systems, simply because today's aircraft have onboard systems that begin investigating what is working and not working as soon as they land.

And even in the 1960s, people had noticed how noisy it was. That is because of another immutable fact about air and engines: the noise created by an engine is strongly determined by its exhaust velocity. "If you double that, you get 16 times the noise," confirms Bond. "That's why modern planes have huge fans: they push just as much air as smaller ones, but they're quieter. Concorde makes 80 times as much noise for the same thrust as a Jumbo."

As a plane that always lived on not one, but three razor edges - economic, political and technical - Concorde was always going to be sensitive to changes in conditions. Any successor would have to fly further, carry more people, make less noise. And that would mean re-testing all those equations.

So is there any hope of seeing another supersonic plane? "I think the Chinese might," says Bond. "They have a big country; they want to deal with the Americans - and that means flying over the Pacific. I think they could, in the next 20 to 30 years." After all, they have only just launched a man into space - but that was a 1960s project originally, too.