S (Sub Surface) Stock
Introduced: 2010 Lines Operated: Circle | District | Hammersmith & City | Metropolitan
Number in Service: 192 Number of Carriages: 7 (S7 Stock) | 8 (S8 Stock) Max Speed: 62mph
The S7 & S8 Stock, part of the Bombardier Transportation Movia family of multiple units, was built to replace the life expired A60/A62, C69/77 & D78 Stock units from the Circle, District, Hammersmith & City and Metropolitan Lines.
Introduction of the units began in 2010 when the S8 Stock began to run in service on the Metropolitan Line, the last unit being introduced in September 2012. S7 stock was introduced onto the Hammersmith & City Line in 2012 with the last unit entering service in February 2014. S7 service began on the Circle Line & District Lines in 2013 with the last units entering service in February 2014 (Circle Line) and April 2017 (District Line).
At present S Stock is operated manually, but London Underground will activate automatic train operation once the necessary signalling is in place by 2022.