London Underground 1973 Tube Stock

The 1973 Tube Stock fleet was ordered to replace the mixture of 1938, 1959 and 1962 that operated on the Piccadilly Line. A larger fleet was also ordered as more trains were also needed for the extensions of the Piccadilly Line to Heathrow Airport in the late 1970s [1]. The trains entered service from 1975 and are now the second oldest stock on the London Underground.

Eighty six 6 car units were ordered with an extra 3 car unit for the Aldwych branch, seventy six of these are needed for peak time operation. The trains usually operate with 2 UNDMs in the middle though 20 units can operate as a complete 3 car unit with 2 DMs at either end however service trains usually contain 6 cars. When the Aldwych branch of the Piccadilly Line was still operating then a single 3-car unit was used on it [2].

Number built: 519 (86.5 6-car units)
Built: 1974-77
Builder: Metro-Cammell
Engine: 4 LT118 traction motors per motor car (630v DC fourth rail)
Formation: Driving Motor (DM)+Trailer (T)+Uncoupling Non+Driving Motor
(UNDM)[+UNDM+T+DM] (some as DM+T+DM)

At 18m long the 1973ts cars are longer than previous tube stock (which were usually around 16m long) this allowed for 6 car trains instead of 7 as was the case before with virtually the same capacity but a reduced cost due to smaller number of bogies, car bodies et cetera [3]. The 1973ts was refurbished by Bombardier in the late 1990s and has regularly been London Underground's most reliable fleet of stock [4].

The 1973ts is due to be replaced in the Deep Tube Upgrade Programme in the mid 2020s. It is possible that some 1973ts cars could live on to be used to replace the ageing 1938ts/Class 483s on the Isle of Wight Island Line.
235 at Acton Town

Ealing Common

Approaching Acton Town

157 at Acton Town

Another 73ts at Acton Town

Passing through Ravenscourt Park

[1] John Glover, London Underground Rolling Stock in Colour (Ian Allan, 2009) p. 8
[2] Anthony Badsey-Ellis and Mike Horne, The Aldwych Branch (Capital Transport, 2009) p. 72
[3] J. Graeme Bruce, The London Underground Tube Stock (Ian Allan, 1988) p. 114
[4] John Hawkins, "LU Train Reliability", Underground News No. 644 (August 2015), p. 458