London Underground A60 and A62 Stock

Infobox Underground stock


name=A60 and A62 Stock
InService=1960-present (A60)
1962-present (A62)
Manufacturer=Cravens
LinesServed=East London
Metropolitan
CarLength=16.17 m
CarWidth=2.95 m
CarHeight=3.70 m
MaxSpeed=70 mph
(capped to 50 mph)
Weight=21.8-32.1 tonnes
SubsurfaceStock=true

The A60 Stock is a class of sub-surface train run on the London Underground, and was built in 1960 by Cravens of Sheffield for the extension of the electrification to Amersham. The A62 Stock is a batch of almost identical units, built in 1962 for Uxbridge services. They are both commonly known simply as 'A' stock, as there is no need to distinguish between the two batches (or between them and the 1903 trains, also known as "A Stock"). The only significant difference between the A60 and A62 types is their compressors: the A60s are fitted with rotary compressors whereas the A62s have reciprocating compressors, and the different sound of these can act as an identifying feature.

The 'A' in the unit designation stands for 'Amersham', as the trains were ordered as part of the electrification of the Metropolitan Line to that station.

The trains were required to be a compromise between the needs of longer distance 'outer suburban' passengers on the outer reaches of the line and short distance 'urban' passengers over part of the heavily trafficked Circle line. For this reason they feature three sets of doors per carriage.

They work in an eight-car permanent formation on the Metropolitan Line, and in a four-car formation on the East London Line until 22 December 2007 when the line was closed for refurbishment and extension. One four-car unit operates the Chesham to Chalfont & Latimer shuttle. They were refurbished by Adtranz (now Bombardier) Derby in the mid to late 1990s.

When built they had a top speed of 70 mph (World's fastest 4-rail train), and operated at this speed until the late 1990s/early 2000s. They are capped now to only 50 mph to improve reliability. Despite this, these trains are the fastest on the London Underground network. The A60/62 trains are the only ones left on London underground that still feature independent brake and traction control.

A distinctive feature of this stock is 'transverse' seating. Being designed for journeys which can last over an hour, the seating is of the high capacity 3 + 2 design, being oriented across the car's width as opposed to a longitudinal layout, where seats are arranged along the sides of the carriage. Nevertheless, despite each 8-car train seating 448 passengers, these trains still provide fewer seats than the locomotive-hauled and T stock trains they replaced. However, the stock will provide more seats than the S Stock, which will replace the A Stock from 2009.

For the convenience of longer distance passengers the A stock is also equipped with luggage racks and umbrella hooks, being the only stock on the system to have these features thus being dubbed as the only "proper" train on the system. This is the reason why many find this train the most comfortable train to travel on out of all the stock operating in the underground. [cite web|url=http://www.railforums.co.uk/archive/index.php?t-82.html|title= Best LUL stock poll]

At 9'7" by (approx 2.95 m) these are London Underground's widest trains. [cite web |url=http://www.trainweb.org/tubeprune/Dimensions.htm|title= London Underground Rolling Stock Dimensions|accessdate=2008-04-03 |publisher= London Underground]

Replacement

An order has been placed for new rolling stock to replace the A60 and A62 units. On the Metropolitan Line, the new S Stock will enter service around 2009, while the East London Line will receive new Class 378 Electrostar rolling stock once its extensions are open.

Although the S Stock trains are expected to be physically identical for all the sub-surface lines (Metropolitan, District, Circle and Hammersmith & City) Metropolitan trains will be 8 car, not 7, and will be a separate sub-fleet. It is likely that the Metropolitan S Stock will have more seats than those trains for the other lines.

References