The 1973 Tube Stock operates on the Piccadilly line of the London Underground and was introduced in 1975 for the opening of the extension to Heathrow Central (now Heathrow Terminals 1, 2, 3).

Construction

A total of 88 trains were built in 1972-75 by Metro Cammell in Birmingham. They entered service between 1975 and 1977 and were later refurbished by Bombardier Transportation. The stock was refurbished between 1996 and 2001; the last unrefurbished train was despatched from Northfields depot in early 2001 before re-entering service in July of that year. In 2005 an upgrade was made to the seats involving the royal blue seat moquette. Like all London Underground trains, they operate on a four-rail 630 V DC power system.

Operations

The Piccadilly line's 1973 stock trains are kept in depots at Cockfosters in the north-east and Northfields in the west. They are painted in the London Underground corporate livery - blue, white and red.

76 1973 stock trains are required for peak Piccadilly Line service.

Former rolling stock

The 1973 Stock was built to replace the 1956 Stock, 1959 Stock and the (seven) 1938 Stock trains formerly used on the Piccadilly line. The opening of the extension from Hounslow West to Heathrow Central necessitated the construction of new trains, which would also need to be suitable for passengers with large amounts of luggage. The trains thus have extra space by the doors to allow for the luggage of passengers travelling to Heathrow Airport. The 1956/1959 Stock was subsequently transferred to the Northern line and the 1938 Stock trains were scrapped.

Announcer system

The stock was fitted with a non-standard type of Digital Voice Announcer (DVA)(Julie Berry). Rather than other lines, which use wheel counters or GPS to automatically provide announcements, the 1973 stock announcements had to be operated manually by the driver keying in a unique code. This being rather cumbersome, most drivers made their own announcements, if at all. In November 2006, the system was changed to an automated announcer with a simultaneous upgrade to the dot matrix displays in the carriages. The driver can also select two settings "commuter" and "tourist". In addition to this, the driver can add extra announcements through a code for example "please stand clear of the doors" or "Let customers off the train first please"

In addition, the "alights" are missed out of the "commuter" setting.

The "Alight" sections include:

King's Cross St. Pancras tube station: "The Royal National Institute of the Blind"

Russell Square tube station: "The British Museum"

Covent Garden tube station: "London's Transport Museum"

Green Park tube station: "Buckingham Palace"

Knightsbridge tube station: "Harrods"

South Kensington tube station: "The museums and Royal Albert Hall"

Earls Court tube station: "Earls Court Exhibition Centre"

Holborn, Knightsbridge and Barons Court Stations are examples of stations which have an exclusive announcement due to their gaps: "Please mind the gap between the train and the platform."

In December 2007, the Piccadilly Line added St Pancras International to its dot matrix display and Digital Voice Announcer (DVA). The reading is as follows: "This is Kings Cross St Pancras. Change here for the Victoria, Northern, Hammersmith and City, Metropolitan and Circle Lines and national and international rail services".

In March 2008, the system went through another change - it has been the second announcer system to have the feature of saying "Please mind the gap between the train and platform" at the station before any other announcement, e.g: "Please mind the gap between the train and the platform. This is Barons Court. Change for the District Line. This is a Piccadilly Line service to Heathrow Terminals 1,2,3 and 5"

Additionally Hatton Cross and Hounslow West now plays an announcement to inform passengers about how to reach terminal 4 or 5 depending on the service.

Replacement

The 1973 Stock is scheduled to be replaced in 2014 by the proposed London Underground 2014 Stock.

Numbers

DM	DM	UNDM	T
100 - 253	854 - 895	300 - 453	500 - 653

Unit formation

Each train is made up of two units of three cars:

DM - T - UNDM + UNDM - T - DM

Some units are also formed with a second DM in place of the UNDM - these are known as "double ended" units. A Driving motor car (DM) has a driver's cab and traction equipment. A trailer car (T) has neither cab nor traction equipment. An Uncoupling Non-driving motor car (UNDM) has traction equipment without the driving cab, though it has control for purposes of uncoupling and shunting.

All trains in passenger service operate as two units, trains are only permitted to move as a single unit in depots. However one single double ended unit was used to operate the peak-hour Aldwych branch shuttle service, until the branch closed in 1994.

External links

• Transport for London - 1973 stock specifications
• Tubeprune - 1973 Tube Stock
• London Transport Museum Photographic Archive