This page was fully revised on 17 August 2008, and
last modified on 8 November 2010.
The 1973 tube stock was built specifically for the Piccadilly Line; since its entry into service, during the period 1975–79, it has formed the entire Piccadilly fleet.
It replaced the 1959 stock which was cascaded to the Northern Line. As its delivery progressed, so did the Piccadilly Line’s extension towards Heathrow airport—first from a remodelled Hounslow West to Hatton Cross in 1975, and then onward to Heathrow Central (since re-named Heathrow Terminals 1, 2, 3) in 1977.
The 1973 tube stock was quite revolutionary at the time of its introduction. Its cars are somewhat longer than seen on previous types, and the trains are made of two 3-car units rather than the previous 3+4 formations to simplify maintenance and provide space near the doorways for airport-travellers’ luggage.
Most 3-car units are formed DM-T-UNDM, but 21 double-ended units were provided and have driving cabs at both ends.
It was the first stock on the Underground to do away with the Westinghouse Automatic Brake. The latter had provided fail-safe braking using the Train Pipe carrying compressed air which, if exhausted, caused the brakes to apply. Instead of a pipe, this stock has an electric wire which, if de-energised, causes the emergency brakes to apply. This is the round-the-train circuit, into which are connected items of safety equipment such as the tripcock, deadman handle, and emergency brake buttons. This system was adopted on all subsequent stocks.
The LT118 traction motors produce both tractive effort and rheostatic braking under Pneumatic Camshaft Mechanism control, as with stocks of the previous half-dozen years; however the 1973 stock incorporated control of both motoring and braking using one single camshaft.
Roger Viggers adds:
When built the platforms did not extend all the way to Northolt Road, the building at the front end of the present platform was the booking office etc.
The platform extensions, stairs and new booking hall were built in the 1930s and the stopping point for trains moved closer rendering the original platform length surplus. The original station building then became the Station Manager’s office and traincrew accommodation.
The 1973 tube stock fleet was refurbished in the late 1990s and early
2000s at Bombadier Prorail in Horbury, Wakefield; among the
improvements are the painting of the exterior in LU corporate livery
(previously this stock was finished in bare aluminium apart from half-red
cab-fronts), re-working the car interiors completely, and fitting a new passenger detrainment system in the
cabs. The final unrefurbished train in passenger service was Train 357,
formed by units
860+251 in the morning of Monday 21 August
2000; it is presumed to have been exchanged during the day as it was
officially “stopped” the same day. The last re-entry into
service following refurbishment was unit
894 on 10 July
The general design appears to owe much to the 1967 stock, with long dual-glazed windows in the saloons and wrap-around windows in the cabs. However, these cars are longer and have enlarged “stand-back” areas around the doorways; yellow labels visible above indicate that baggage should be placed there. Whether foreign travellers just arrived via Heathrow would agree with the security aspects of this is questionable.
The refurbishment programme included a total re-working of the car-interiors:
Both photos were taken at/near Cockfosters, on Friday 21 May 1999.
The cab interior of brand newly refurbised unit
145), which had in fact come direct from Ruislip (and
Wakefield) to Steam On The Met 1999’s rolling-stock
display at Rickmansworth, without entering service first. Despite the
provision of apparently more comfortable and spacious surroundings for
the driver, the opinion generally seems to be that the unrefurbished cabs
were preferred. Note the distinctive tapered wrap-around driving window,
seen from this unusual perspective.
At extreme right, with the yellow key in the top, is the selector switch; this is used to select forward, reverse, (automatic is not connected!), a test mode and to shut the train down. The deadman’s handle is in the centre of the picture, where the driver’s left hand would be; its proper name is the Traction Brake Controller. The driver keeps it held down and then rotates it towards him to select Shunt, Series or Parallel motoring, and moves it away from him to select Coast, Hold, three rates of braking and Emergency, plus a Shutdown position. On the desk are door and whistle controls, and an automatic announcer system controlled by the box on the wall. Out of shot to the right is the front door of the train, with a Public Address / Radio handset mounted nearby. The recess nearest the camera is a drinks-holder.
The refurbishment of the 1973 stock incorporated the first example of
an entirely re-thought means of providing an emergency exit via the front
and/or rear of Underground trains. Earlier arrangements consisted of a
little wooden fold-up Emergency Ladder that is stowed under a seat in the
passenger saloon (cantrail marking
EL), and this would be
hooked into position; it had to be descended facing backwards.
The refurbished 1973 stock has a ladder with handrails which is integral to the cab-front, with the steps sliding under the cab floor and the handrails folding up against the front of the train; passengers can now be led directly out of the train with a handrail to hold on to. At top right is a lamp for illuminating the emergency detrainment procedure, and at the extreme ends of the solebar are a further two low-voltage lights for the same purpose. Other features visible include the yellow calling-on light (above the other cab window), and the yellow TripCock Isolating Cock (TCIC) on the left of the solebar, in the “cut in” position.