Made of wood, with no engine and few seats, the first look at a Boris bus

It is made mainly of wood and plastic and has neither engine, driver, conductor nor even many seats.

But it brought to life for the first time the Mayor's £7.8million vision that may soon be dubbed the "Boris bus".

The Evening Standard was given a sneak preview of the life-size replica being built by Northern Ireland firm Wrightbus in advance of the completed model arriving in London next month.

The first bus will take at least another year to be delivered and will undergo testing - possibly picking up passengers in the capital - in about a year.

Six will then enter service in January 2012, concentrating on central routes that call at the busiest rail stations.

The roll-out has yet to be agreed but TfL says 600 could be in central London by Christmas 2012. The bus is designed to be more accessible than a conventional double-decker, with two staircases and three sets of doors at the front, middle and back. This restores the rear open platform beloved by many passengers as it allows them to hop on and off if it gets stuck in traffic.

"It's revolutionary and will be pop- ular because it's easy on, easy off," said William Wright, the 80-year-old group director of Wrightbus, which he founded with his father in 1946.

"We were given a blank sheet and we tried to move the bus into the next century. I think customers will like it.

"London and the Mayor deserve a great deal of credit for having the nerve to go ahead. A lot of cities will take advantage of what they've done."

Engineers at the firm believe they have ach- ieved a design breakthrough by creating a rear door that can be locked open when a conductor is on duty - in peak daytime periods only - yet be opened and closed remotely by the driver at other times.

The vehicle also has a hybrid diesel and electric engine half the capacity of a conventional double-decker and will have 40 per cent fewer emissions.

Each will have an Oyster card reader and carry 87 passengers - 25 standing - who will not need to show the driver their ticket. There will be space for a wheelchair. The old Routemaster, withdrawn in 2005 as it breached disability laws, seated 72, with five standing.

The Mayor's transport adviser Kulveer Ranger said TfL will hold the patent but added: "We'll be happy to see the bus in Hong Kong or Las Vegas."

Stephen McMaster, a coach builder at the firm, said: "This may well be the bus of the future."