TRANSPORT for London has awarded a controversial signalling contract for the second time, but the price has more than doubled and the deadline for completion has slipped by several years.

The £760 million project is to upgrade the signalling on the subsurface lines of London Underground -- the Metropolitan, District, Hammersmith & City and Circle -- which between them account for 40 per cent of the network's 400 route kilometres, and will be carried out by Thales. TfL said some of the existing signalling 'belongs in a museum', and that new equipment would allow an essential boost in capacity.

The project to modernise train regulation on the subsurface lines was awarded to Bombardier in June 2011 for £354 million. However, that bid was based on Bombardier equipment which was already in use in Spain and China, and the company withdrew from the deal two and half years later, after admitting that the 'fit' between its systems and the 'old and complex' Underground network was not right.

At the time, Transport for London said "at this stage there is no change to the original delivery timetable of 2018", but it now says that 'main benefits' of the upgrade will be seen in 2022.

Bombardier had already carried out preparatory work and built a unified control centre before it withdrew from the contract, for which it was paid a reported £80 million. If this is approximately correct, the total cost has risen from £354 million in 2011 to around £840 million now.

Transport for London has said that the two figures are not comparable, partly because of inflation but also because the original Bombardier contract did not cover all the modernisation work which is being done now.

The outgoing transport commissioner Sir Peter Hendy later said the collapse of the original Bombardier deal was a 'severe embarrassment', and he was reported to have been angered by it. Even so, Bombardier went on to win the £1 billion contract to build the new Crossrail fleet, also awarded by TfL, and signed another TfL rolling stock contract, for new Overground trains, at the end of June this year.

Transport for London said the new deal with Thales will boost capacity by a third and create up to 1,100 jobs and 60 apprenticeships. The contract follows major upgrades on some of the deep tube lines, including the heavily-used Victoria Line. After track upgrades have been completed by the end of August, the Victoria will be able to provide 36 trains an hour. Meanwhile, Alstom has recently completed a mid-life refurbishment of the Northern Line fleet.

London Underground managing director Nick Brown said: “Having successfully modernised three of the most heavily used lines on our network, we are ready to begin work to bring the next four lines into the modern era. This will transform the journeys of millions of our customers, significantly increasing service reliability and frequency. 

“We have a very clear delivery plan and timetable for the work and, as we have done with the modernisation of the Northern line, we will keep London moving and growing as we do it. In parallel, we will continue to deliver a better, more reliable service every day which builds on the work over recent years to reduce delays to their lowest ever level.”

Transport for London is also making comparisons between the value for money offered by the new Thales contract and the former public-private partnerships. It said: "The value of the contract with Thales for the signalling and control work is £760 million. The cost per kilometre of re-signalling the four lines is 18 per cent less than the successful modernisation of the Northern line which was around half the cost of the Jubilee and Victoria line modernisations delivered under the flawed Public Private Partnership arrangements, ended by the Mayor five years ago."

Work on the subsurface resignalling project is now expected to start later this year.