S-Stock rolled out on London Underground's District Line

New Bombardier S-Stock trains entered service on the London Underground District Line’s Ealing Broadway branch on June 13. Just four days later, operations were extended to the Richmond branch as well.

This follows the first S-Stock passenger service that ran on the Wimbledon branch on February 7 (RAIL 742), and further rollout on the branch later the same month. The S-Stock has replaced 40-year-old C-Stock, which ran for the last time on June 3 on the Edgware-Wimbledon branch of the District Line.

Signal sighting tests were carried out in May in preparation for the S-Stock’s introduction (RAIL 749).

The seven-vehicle ‘S7s’ have already entered service on the Hammersmith & City and Circle Lines, making the District Line the last of the sub-surface Tube lines to receive this configuration. 

Eight-car ‘S8s’ have been in service on the Metropolitan Line since 2010, and all have now been delivered. However, the ‘S8s’ have been returning to Bombardier’s Litchurch Lane works for modifications to improve the interior aesthetics and functionality, as well as modifications to the bogie and axle components to provide longevity.

‘S7s’ were not included in the modification work programme - the vehicles were built later, and so included the changes as part of the build process.

An equivalent to the S-Stock is currently being investigated for the deep-level Tube lines, as part of LU’s ‘New Tube for London’ programme. LU is currently looking for a supplier for these trains (RAIL 744), which will feature air-conditioning and walk-through gangways, as is seen in the S-Stock. An Invitation To Tender is expected to be issued in early 2015, seeking a supplier for 250 trains.