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A60/62 stock

This page was last modified on 9 December 2002.

Introduction

The A stock was built by Cravens of Sheffield in two batches, designated as A60 and A62. It is used on the Metropolitan Line, from Aldgate and Baker Street to Amersham, Chesham, Watford and Uxbridge; it also serves the East London Line, formerly part of the Metropolitan system. Trains are made up from four-car units, with all trains being eight-car except those working the East London Line and the Chesham shuttle; each unit consists of two Driving Motor cars sandwiching two trailer cars.

OPO conversion

Following modifications to slightly more than half the driving cabs to equip the stock for One Person Operation (OPO), most units can be driven from the "leading" cab only: the "middle" cab is not fitted with door controls and train radio, and can only be driven from with the train empty, and the driver in contact with control using a portable train radio. This is not a particular hardship until the depots run out of A-end units and have two D-end units with no way of deploying them, and one more train required imminently... All other types except C stock and 1992 stock work on the same principle, except that some types have no cab at all in the "middle" position, just a cabinet with rudimentary controls to allow shunting movements. As with 1973 tube and D stock, there are some double-ended units of A stock, having a working cab at both ends, to give greater flexibility and to provide reversible trains for the Chesham branch and East London Line. On A stock (as on 1967 and 1972 MkII stocks), active cab-ends are painted red while "middle" cabs carry the blue and white livery of the bodysides.

Further description

Metropolitan Line journeys can be more lengthly and less crush-loaded than, for instance, Circle Line trips, and so all the seating is transverse 3+2 with headrests. A bone of contention at the time of customer acceptance for the A stock was the provision of `parcels racks' for briefcases and coats, and especially umbrella hooks which are still in place today. These features, together with the choice of stopping, semi-fast and express services over the line, all help to set the Met apart from the other Underground lines and give it its suburban-line feel. The heavy refurbishment of the entire fleet was completed during January 1998, and entailed the repainting of LUL corporate livery, redesigned interiors and, equally importantly, improved suspension and brakes. The quality of the work is such that many people are convinced the trains are brand new, despite their being nearly 40 years old!

Following the withdrawal of the Northern Line's 59/62 tube stock, the `A' subsurface stock is the oldest type in passenger service on London Underground, and the only one to retain separate controls in the cab for motoring and braking. Although it is expected to be replaced with a generic Subsurface stock, this is unlikely to happen before the stock's 50th birthday in 2010.

Above: South-facing D-end unit number 5207, looking smart in LUL corporate livery, approaches Finchley Road southbound as train 414, heading to Baker Street.

Just behind the caged-in ladder leading up to the cable-gantry on the left, a gap in the sequence of red doors can be seen: this is where the two single-ended units are coupled back-to-back, and the "middle" cab ends are painted to match the bodysides. Careful examination also reveals that the motor cars at either end of each unit have a single-leaf door right at their non-cab ends, whereas the trailer cars have three evenly-spaced sets of double doors. The single-leaf doors are a reminder that Guard's positions used to be located at those points (as on other stocks), prior to disuse after OPO conversion and removal during refurbishment.

The track worker wearing the regulation hi-viz suit is acting as lookout-man for a signal engineer working out of shot to the right; the lookout blew his whistle and waved his flag about ten seconds before this picture was taken, and the Train Operator also gave a quick blast on the train whistle on spotting the lookout-man. (Friday 8 January, morning.)

Above: The next southbound Met service was train 405 heading to Aldgate.

I'm confused by the fact that unit 5006 is leading, because it is an A-end unit and should be facing northwards. 5006 isn't a double-ended unit so it must have got `turned' on the Watford triangle, probably by working an early-morning one-way service over the Rickmansworth — Watford curve. The signal engineer who was being protected by the lookout man in the previous shot can be seen in a `place of safety' on the left; he was lubricating the train-stop seen beneath the right-hand side of the train. The signal commanding that train-stop is MD27, part of which can can be seen to the top left; it allows northbound workings over this southbound platform track, the area having been equipped with bi-directional signalling. "MD" refers to Baker Street control centre. Beneath the signal and partially obscured is a Rail Gap Indicator, which displays a triangle of red lamps if the traction current is discharged in the section ahead; the unsightly cabinet obscuring part of it is an anti-glare box containing CCTV monitors, installed for OPO, which show the Train Operator what is happening on the platform.

Visible in the windscreen above the train number and headlights is a yellow square; this is the Flag Switch, and consists of a rotary switch which raises the yellow "flag" into view in the `on' position: it allows the driver to enable or disable Weak Field operation. Traction motors running in equilibrium can be made to go faster by reducing the strength of their (electrically-provided) magnetic field; this of course takes more current and is only worthwhile for longer high-speed runs. Thus it is normally enabled on Metropolitan Line trains, and the weak field notch comes in by itself after the current drops below a given level in Full Parallel operation; on lower-speed lines mostly in tube, such as the Northern Line, use of the Flag Switch was prohibited everywhere (of course this is now irrelevant, no Northern Line trains have a flag switch!).

This unusual view of A stock was afforded by the Emergency Response Unit's demonstration of how they re-rail trains that have come adrift; this was amongst the rolling stock displays at Rickmansworth sidings, Steam On The Met, 1999.

Visible are the Automatic Coupler and the sprung buffer above it (which shows that this (unidentified) car is a `D' end car). On the headstock can be seen the red Dead-Man Valve Isolating Cock (at right hand side), the TripCock Isolating Cock (just below headlights) and Unit/Train Isolating Cocks below that. The white-painted pair of step-rungs provide means for the driver to get into or out of his cab from track level. All Underground trains — except those on the Victoria Line — are fitted with Correct Side Door Enable (CSDE), which prevents the passenger doors being opened when there is not a platform alongside all of them; this is done by a loop of cable on the platform-edge (or opposite it, on some lines) whose magnetic field is picked up by a sensor on the train. The A-stock's sensor, a little probe that looks rather like a geiger-counter, can be seen pointing sideways from its mounting-bracket just below and to the right of the white steps.

In the driving cab

Above: This is the instructor's view of the oldest driving cab layout in daily use on the Underground.

In sharp contrast to all other service stocks (eg C stock), this type has separate controls for motoring and for braking the train; it is also the only type to be fitted with hinged cab-side doors (all the other stocks that have cab-side doors at all have air-operated sliding doors similar to those found in the passenger areas). The cab interior was painted a "restful" (?) shade of sky blue during refurbishment, but the equipment has remained essentially unchanged. Beyond the fold-down driving seat is a panel with controls for the headlights, tail lights and control governer (to name three). The sticker at the bottom of the `M' door (at right) reminds the driver of the need to follow correct procedure when passing signals at danger, and also that "unauthorised persons are not allowed in the driving cab"; the outward-facing reverse side of the sticker carries the "Metropolitan Line" legend.

In the foreground is the upward-sprung "dead man's" handle of the Master Controller; when a direction is selected using the Reverser key (hidden behind deadman) the handle must be kept depressed or else the brakes will be applied. At each station, if the driver wants to rest his hands he must move the Reverser key back to the Off position, after which he can safely remove his right hand from the master controller.

The brake handle (or, to give it its full name, the Driver's Brake Valve handle) is under his left hand and difficult to see from this angle as it is facing away from the camera; its hexagonal brass domed nut can be clearly seen. To make a brake application the driver would rotate the handle anticlockwise, the amount of rotation determining the amount of brake applied at any time; this caters for the normal, Electro-Pneumatic (EP) braking. However, if he wishes to use the Automatic Westinghouse brake (which is fail-safe and is applied automatically if anything goes wrong) he must "throw" the handle to the six-o'clock position and then control the pressure in the Brake Pipe from there. Finally, an Emergency position is provided (at about eight o'clock) which exhausts the Brake Pipe to the atmosphere and additionally gives an EP brake application equal to 30lbs of brake cylinder pressure.

Other things visible in this cab include the pressure gauges, pilot light, speedometer and car number (5014), on the corner pillar; newly-resited door controls on the panel beneath the driving window; and Train Radio controls at top right.

Thanks to Duncan Fenton for supplying the sentence about parcels racks and umbrella hooks.