Two major gripes of London’s Underground system will be answered in full when new Crossrail trains come on line in a couple of years.

The new rolling stock will be both wi-fi enabled and air-conditioned, London Boris Johnson said as he unveiled the design on Friday (November 20). Wi-fi and 4G connectivity will be available on the platforms and trains throughout the route.

The trains, built by Bombardier Transportation’s UK factory in Derby, will have space for 1,500 customers in nine walk-through carriages. Each train will be more than 200m long – the size of two full-sized football pitches or 18 Routemaster buses.

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They will also put electricity back into the network when braking, meaning they will use 30% less energy. They will be in service from May 2017.

Mr Johnson said: “I am delighted that these British-built trains have been designed with customers at their heart, with on-board facilities that are fit for a truly 21st-century rail link.”

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Rail minister Claire Perry said: “The spacious layout and longer trains will provide a significant boost to London’s rail capacity, meaning better journeys for passengers, and transforming the way people travel between east and west.”

The trains will have wide interconnecting gangways and three double doors on each side of each carriage, providing high capacity and quick boarding and alighting times as well as real-time travel information on board.

Timetable for introduction of Crossrail services

  • Liverpool Street to Shenfield – May 2017
  • Heathrow to Paddington (mainline platforms) – May 2018 (when the Crossrail concession takes over the Heathrow Connect service)
  • Paddington (Crossrail platforms) to Abbey Wood – December 2018
  • Paddington (Crossrail platforms) to Shenfield – May 2019
  • Full through service (including services to Reading) – December 2019