In 1933, the Great Western Railway introduced the first of what was to become a successful series of diesel railcars, which survived in regular use into the 1960s, when they were replaced with the new British Rail "first generation" diesel multiple units.

Design

Bodywork

The original design featured streamlined bodywork, which was very much the fashion at the time. The rounded lines of the first examples built led to their nickname: "flying banana". The preserved W4W is an example of the original, rounded body shape. Later "razor edge" examples, such as No. 27 (pictured), had much more angular (and practical) bodywork, yet the nickname persisted for these too.

Heating

The interiors of railcars No. 1 to No. 18 were heated by using waste heat from the engine cooling water. This system proved unreliable in service due to issues with the thermostatic valves. Later vehicles abandoned this system due to its unreliability and because their revised specification demanded that they be able to haul steam-heated rolling stock.

Railcars No. 19 onwards were powered by a modified version of the previous engine. This engine was equipped with direct injection and the bore diameter was enlarged to 120 mm, the stroke remaining at 142 mm. This engine produced a lower brake power output of 105 hp at 1,650 rpm.

Operational history

thumb|left|200px|1934 publicity photograph.

Constructed by the Hardy Rail Motors subsidiary of AEC, the prototype unit, No. 1, made its first run on 1 December 1933 between London Paddington and with a large number of press representatives. Three days later, the unit was allocated to Southall DMU Depot to operate on various services from to , Windsor, , Reading and . This was done primarily as an experiment, and to increase the punctuality of stopping passenger services out of London by having parcels moved by a dedicated unit. This would ultimately prove a success, with No. 17 operating from to , Messrs. Lyons to Reading and , Oxford to London Paddington, and then from London Paddington to Reading and back, a daily distance of .

|-

|align=center|2–4

|align=center|1934

|rowspan=1|Park Royal

|rowspan=6|2 AEC of

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|44

|align=center|1954–1958

|Buffet fitted.

|align=left| Static display

|130px

|-

|align=center|W20W

|GWR Swindon

|align=center|1940

|Kent & East Sussex Railway

|align=left| Under restoration at Tenterden since 1983

|130px

|-

|align=center|W22W

|GWR Swindon

|align=center|1940

|Didcot Railway Centre

|align=left|Operational

|130px

|}

Models

Hornby Railways manufacture a model of the 1940-style railcar in OO gauge, using tooling acquired in their takeover of Lima. In late 2017, Dapol released an OO model of the streamlined 1936 Gloucester RCW railcars in a variety of liveries and numbers. Heljan manufacture a model of the 1940-style railcar in OO gauge, using new tooling, that includes internal lighting and front and rear lighting.

Graham Farish produced an N-gauge model (with various numbers, e.g. 19, 22, and 20), both before and after their takeover by Bachmann.

See also

  • GWR petrol-electric railcar
  • GWR steam rail motors
  • GNR(I) AEC Class railcars
  • ČSD Class M 290.0

References

Further reading

  • The Great Western Archive
  • British Diesel Rail Coaches