The Last Routemasters: The conductor's bell tolls for these

Philip Thornton laments not just the end of a line, but also the lack of imagination of London's bosses

If London were a brand rather than just a world city, it would fight tooth and nail to defend its distinct image against all-comers. Imagine the response of McDonald's to a rival appropriating its giant "M" or Nike discovering a shoemaker had copied its "swoosh" logo. But it seems London - or at least its collective masters - seems hell-bent on removing one of the remaining images that make the city immediately identifiable around the world - the Routemaster.

The final route to go is the number 159 from Marble Arch to Brixton, which retires on 9 December. From then London will have no Routemasters operating full-time on a regular bus route for the first time in 51 years. Although 10 were transferred to two "heritage routes", you will probably find more running in India than in the city of their birth.

The bus's curves are more appealing than the box-shape of the modern design. But more important is the fact that as a method of urban transport, it is very efficient. Its two-person crew means that the bus only need stop long enough for all the waiting passengers to get on board, as the conductor can collect fares on route. On other buses the driver can't move off until he or she has collected the fares and checked all the tickets - a process that can be severely delayed by the person who can't dig the correct change or pass out of their pocket.

No one is eager to shoulder the blame for the disappearance. The bus operators say it is a decision for Transport for London (TfL), the capital's transport authority - although conversion to one-person-operated buses improves their wage and pension bills. TfL says legislation outlaws buses that cannot accommodate the physically impaired - even though it will not take effect until 2017.

But most people blame Ken Livingstone, the Mayor of London, who said in 2001, after his first election, that "only a ghastly dehumanised moron would want to get rid of the Routemaster". Two years later he stood for re-election with a pledge to retain the iconic vehicle. But Livingstone says that it was right to replace them with buses that were easier for parents, shoppers, the disabled and elderly to use. "The time was long overdue for London's buses to be accessible to all," he says. "In the five years that new low-floor accessible buses have been introduced, passenger numbers have increased by 50 per cent, so clearly bus users like the modern fleet."

But perhaps the main unanswered question is why no one designed a replacement that would preserve the best of the old with the benefits of the new. Minis managed to reinvent Alec Issigonis's iconic design and - more pertinently - the new TX1 London taxi combines the familiar curves of the Fairway with full wheelchair access and mod cons such as an intercom.

Back in the 1960s executives at London Transport made one version of a Routemaster with a front entrance, called the FRM, but that proved unsuccessful. At the same time London Transport (LT) made around 100 coach versions with electronically controlled doors. The FRM almost became the XRM, a bus designed by LT with disabled access. According to Travis Elborough, the author of The Bus We Loved, a history of the Routemaster: "They'd put the engine under a central staircase so it could have one or two doors and keep the rear platform - and a conductor, if you liked."

A recent booklet from the Policy Exchange think-tank identifies eight "children of Routemaster" that were offered to London's transport chiefs. The author Andrew Morgan, a founder of the Routemaster Association, wrote: "The designs and technology are there to build a worthy successor to the Routemaster."

Proposals included a plan for a twin-doored high-tech vehicle by Coventry University student, Blake Cotterill, that won a global automotive design award.

Five years ago Colin Curtis, a former LT chief engineer, produced a design for a bus with a flat floor and more accessible staircases and platform. "Several meetings took place with TfL from 2000 but no commitment from them was forthcoming," Morgan said.

It was clear two-person crews were an obstacle. TfL said returning to conductor-and-driver services across London would add £160 to the annual council tax of a band-D property.

Nevertheless, it is depressing that a country that can produce the designer of Apple's computers and iPods has failed to come up with an alternative bus that would please both operators and enthusiasts.