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Established 1996

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  Class 501 Units - Principle Data

Class 501 Units - Principle Data

Number Of Coaches In Unit Three
Formation Of Unit Driving Motor Brake-Trailer-Driving Trailer Brake
Motor Equipment Four 185hp GEC Traction Motors on DMB (740hp for each unit)
Vehicle Weights DMB=47 Tonnes: Trailer=29 Tonnes: DTB=30 Tonnes
Vehicle Lengths DMB & DTB=57 feet 5 inches: Trailer 57 feet 1 inch (minus buffers)

So Why Preserve One Of These ?

The 501s were the last all DC units built for the North London (ex LNWR) 4 rail electrified network. They are a superb example of a standard build being adapted to suit a certain line of route.The GEC control and motor equipment is unique to the class and the type of conrol equipment known as 'camshaft control' became standard on subsequent EMU builds by British Railways after appearing on these units first.

BR Class 501 Unit History

The class 501 electric multiple units (EMUs) ferried passengers on the routes between the London termini of Euston and Broad Street, through the Suburbs of North London and Hertfordshire to Watford, Croxley Green and through West London to Richmond from their introduction in 1957 up until their final passenger days in 1985. They epitomised the suburban electric train; reliable, hard working and taken for granted by nearly every one who travelled and worked on them as just another part of life. The units were built as part of the British Railways standardisation programme, whereby all EMU and suburban loco hauled coaches were to be built to a national common design, with regional differences kept to a minimum. Despite this the 501s were constructed very much in the North London (NL) electric tradition and had more than a few non-standard features.

There were 57 units built, all at Eastleigh works, they were, like all previous NL units formed into three car units. The formation being driving motor, trailer and driving trailer, like previous NL designs there was a guards van at each end of the unit behind the driving cab (on other BR standard designs the guards van was only on the motor coaches), the passenger accommodation was formed of two saloons in the driving coaches and an all compartment layout in the trailer, this gave a seating capacity of 256 for the whole unit. Their introduction led to the replacement of the final examples of LNWR and LMS built NL units, all of which went for scrap save for a single car of the LNWR stock which is now restored at the National Railway Museum.

During their passenger days they never strayed from the routes they were purpose built for, it should be noted that they were able to operate from the 4th rail system only when built as the NL electric lines retained this system until converted to 3rd rail electrification in 1971 when the units were modified accordingly. The multiple control apparatus on the cab front gave them an instantly recognisable front end as opposed to other BR standard types and also meant that they were unable to operate in multiple with any other type of EMU, but as the routes they operated on were isolated from others this never presented a problem. They were little modified from their as built condition except for the 3rd rail conversion already mentioned and the change of seating layout in the intermediate trailer from compartment to full saloon which reduced the seating capacity by 16. The only other change that the traveller would have noticed was the livery changes that came and went; green at first, later modified with the addition of yellow ends, then the green gave way to corporate BR blue and finally on a few of the units in latter life all over blue was replaced by blue and grey colours.

As described they were very much a combination of standard design with a good measure of traditional NL practice thrown in. But they were not without their share of innovation in the area of the traction equipment. The 501s featured a type of traction control apparatus that was called 'camshaft control'. It had first been used on tube trains in the mid 1930s but had since been refined and was used for the first time on a main line unit with the 501s. Camshaft control went on to become BRs standard form of traction control for all units built over the next 20 years.

When their passenger days came to an end in 1985 the bulk of the 501s were towed away and broken up for scrap. A few cars were retained for conversion for de-icing, sandite and test units. Ten of the motor coaches were also converted into battery-electric locomotives for use on engineers trains on underground lines in North West London and Liverpool. Over the years since the number of surviving vehicles has continued to dwindle and at the start the year 2000 only six cars remained in existence. The last examples came out of traffic in 2002 having been in use on Sandite and De-icer duties on Merseyside

Units pass south of Harrow And Wealdstone in 1962.

Photo: Fred Ivey

A unit painted in the final version of EMU green
pictured outside Croxley Green depot in 1962

Photo: David Hibbert

501 180, the last unit to receive an overhaul, is seen at
CroxleyGreen depot after works visit in July 1984

Peter Lindop

Throughout their passenger careers the 501 units were
based at Croxley Green depot. In the last months
before final withdrawal a line up of units is
pictured inside the shed.

Peter Lindop

Did You Know.........

These units were fitted with window bars because it was too dangerous to have the risk of passengers leaning out of the windows in Hampstead Tunnel on the line from Broad Street to Richmond where very tight clearances existed. These units came with air operated warning horns from new and were among the first multiple units in Britain to be so fitted. The horns had to be mounted under the buffer beam as they could not go on the roof due to concerns they might be knocked off in the tight space of Hampstead Tunnel.