Piccadilly Line's new air-conditioned trains delayed by a year in blow to heat-hit Londoners

The new fleet of Piccadilly line trains was expected to be up and running by the end of 2025 before the date was pushed back (Picture: Siemens)

The launch of the new,air-conditioned Piccadilly line Tube trains has been pushed back by a year.

Londoners have been at the grips of a heatwave,with many facing an unbearably hot commute on the Underground as temperatures reached 33°C.

Only a handful of Tube lines currently have a cooling system,and new Piccadilly line carriages will be the sixth route with air conditioning once they launch.

The new Piccadilly line trains were due to be up and running by the end of 2025,but now this has been pushed back into next year,TfL revealed.

A CGI visual showing what the new Piccadilly line trains will look like (Picture: PA)

Transport for London had initially said the fleet of 94 new deep-level trains with 10% more capacity and walk-through carriages would be ready this year.

The ‘pioneering’ train is the first deep level Tube train with air conditioning in London,with the system placed under the train to save space.

However,after the novel trains were delivered and assessed by engineers,they found testing to get them ready for integration and passenger service will be ‘more complex than expected,’ TfL warned.

Stuart Harvey,TfL’s chief capital officer,said: ‘We’re proud and excited that these innovative new trains on the Piccadilly line will have a transformative effect for London.

‘This hugely complex project will boost capacity and make journeys more accessible and more comfortable for millions of people.

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‘But I would like to assure Londoners and visitors to our city that we are working extremely closely with Siemens to ensure that the new trains can be introduced as soon as possible in the second half of next year.’

Sambit Banerjee,the joint CEO of Siemens Mobility,said: ‘We’re sorry we can’t have our innovative trains running for passengers even sooner but,once they’re in service,the technology on these new trains will bring smoother,greener and more comfortable journeys for Londoners for the next 30 or more years.’

The Piccadilly line fleet has been serving Londoners since 1973,but they are in need of a revamp as passenger numbers and needs have grown.

Once the 86 trains are phased out,the line will have 27 trains every hour instead of the previous,meaning one train every 135 seconds at peak times.

Some of the new carriages were vandalised after they were delivered to the depot last year,months before they could even enter service.