Is the age of supersonic passenger travel well and truly over?

It might as well be. After October this year, Concorde, the only supersonic passenger jet in service, will be mothballed forever. The plane's demise was triggered by two big problems: not enough bums on seats and spiralling maintenance costs. Concorde can carry only 100 passengers and only turns a profit because everyone flies first class. With companies tightening their belts, more and more seats remain unfilled.

Concorde, like an old jalopy, has been struggling. Ever-rising costs of keeping the ageing fleet in operation meant it made more sense to take the planes out of service. In the last five years, the cost of keeping Concorde in the air has shot up 23%. If kept in service, British Airways estimates it would need to spend $40m over the next five years on basic maintenance for its seven airliners. According to a BA spokeswoman, the plane will never be viable again. "We don't think the market is right now and we don't think it ever will be." The fleet, which includes five owned by Air France, is not for sale.

Rather than pushing for faster and faster planes, the industry is under pressure to make cheaper, more fuel-efficient and quieter aircraft. In 2001, Boeing revealed their plans for the "sonic cruiser", an airliner that would fly at just under the speed of sound. But the airlines weren't keen and Boeing shelved the project last December.

"As well as burning far more fuel, who wants to pay more to get somewhere 45 minutes early, when there's really no need?" says Tore Prang at rival manufacturer Airbus. "Instead, you can just sit back and relax a bit."

Because the cost of developing a new supersonic plane is so high, the big industry players are likely to avoid it for at least the next 30 years, adds Prang.

Concorde was not the first supersonic passenger aircraft to fly. The suspiciously similar Russian TU-144, dubbed Concordski, made its maiden flight in December 1968, two months earlier than a French Concorde prototype. But when Concordski crashed five years later at the Paris air show, its fate as a commercial airliner was sealed. It is now a flying laboratory operated jointly by Russia and Nasa.

One problem Concorde has always faced is a ban from flying supersonic over land, because of the deafening sonic boom it produces. Get rid of the boom and you could open up more routes, sell more planes to cover them and entertain making a profit again. Japan's national aerospace laboratory last year tested a prototype miniature supersonic jet designed not to make a sonic boom. It didn't get the chance to, crashing in the Australian outback seconds after launch.