Railmotor

Railmotor is a term which was used by several British railway companies for a lightweight railcar, that is, a railway carriage with a small steam traction unit or diesel or petrol engine integrated into it.

Steam railcars

Overview

In the earliest days of railways, designers wished to produce a vehicle for passenger carrying that was economical to build and operate on routes where passenger numbers were light. A single coach with its own prime mover was a solution adopted in some cases; this may be thought of as the predecessor to the railcar, a term more associated with the use of internal combustion engines.

William Bridges Adams started building railmotors in small numbers as early as 1848. The Bristol and Exeter Railway used a steam carriage.

In most cases the early designs were unsuccessful technically, but in the early years of the twentieth century, street-running passenger tramways started to use small steam engines to draw tramcars, replacing the customary horse traction. In many cases the tramways soon adopted electric traction instead, and the attractiveness of the cheap and frequent conveyance abstracted business from the railways in urban areas.

The railways responded by opening new stopping places (to serve more closely the new suburban housing) and sought to reduce their operating cost by reintroducing railmotors, which were cheaper to construct.

The London and North Western Railway, Lancashire and Yorkshire Railway, London Brighton and South Coast Railway and Great Western Railway introduced them.

Nonetheless the railmotors had a number of disadvantages: their frequency, and the closeness of their stopping places, could not match that of the tramcars. The intrinsic compromises in fitting a steam engine inside the limited space available made them mechanically inefficient, and their power was (in most designs) insufficient to handle attached vehicles for parcels or additional coaches at times of exceptional demand such as public holidays; and in nearly all cases they still required a three-man crew (driver, fireman and guard), a significant expense compared with the single crew member of a tramcar.

Designs

There were two basic designs:

• A small 0-4-0 or 0-2-2 steam locomotive with one end of a coach hung on it like an articulated lorry.
• A coach with a steam engine built into one end of it. This type would sometimes have a vertical boiler.

These machines were not a great success because they lacked flexibility. Most could haul a single trailer, but no more. This meant they were unable to cope with greater than expected passenger demands – a classic example being busy market days on an otherwise lightly used rural branch line. They were also unable to haul goods wagons, requiring a conventional locomotive to be stationed on the same line in any case for these duties. For this reason, they were largely superseded by push-pull trains and the GWR converted some of their railmotors into autocoaches for this purpose. The South Eastern & Chatham Railway built its P Class of small, light tank locomotives specifically to replace railmotors in the 1900s.

In the late 1920s there was another revival of railmotors with the introduction of new designs from Clayton and Sentinel with high-speed motors and geared drive. The London and North Eastern Railway bought over 80 of them but, again, they were short-lived. Some lasted no more than 10 years and all had been withdrawn by 1947.

From the 1930s the diesel railcar made great progress and by the 1950s the railmotor was consigned to history. The diesel's ability to use multiple unit control was an advantage.

Heritage example

The Great Western Society, based at Didcot, has restored a railmotor built in 1908, and operates it under steam on certain occasions.

Fleets

This list is incomplete; you can help by expanding it.

Operator	Introduction	Withdrawal	Quantity
Barry Railway	1905	1914	2	Converted to bogie composite coaches (Diagram 14)
Bristol and Exeter Railway	1850	1851	1	See Bristol and Exeter Railway Fairfield steam carriage
Cardiff Railway
Eastern Counties Railway	1847
Furness Railway	1905	1918	2
Great Central Railway	1904		3
Great Northern Railway	1905	1927	6
Great Southern and Western Railway (Ireland)	1904	1915
Great Western Railway	1903	1935	99	See GWR steam rail motors
Lancashire and Yorkshire Railway	1905	1948	20	L&YR Railmotors used on the 'Altcar Bob' and other services
London and North Eastern Railway[1]	1925	1948	80	Sentinel steam railcars
London and South Western Railway	1901	1903	15
London Brighton and South Coast Railway	1905		2
New South Wales Government Railways	1923	1983	37	See CPH railmotor
Nidd Valley Light Railway	1921	1929	1	Ex-Great Western Railway
Northern Counties Committee	1905	1913	2
North Staffordshire Railway	1905	1927	3
Port Talbot Railway	1906	1915	1	Sold to Port of London Authority, withdrawn 1926.
Rhymney Railway
South Australian Railways[2]	1906		2	No.1 now preserved in operating condition on Pichi Richi Railway
Sri Lanka Railways	1904		1
South Eastern and Chatham Railway	1904		6
Taff Vale Railway			16
New South Wales Government Railways Creamy Kate and Trailer				Dorrigo Steam Railway and Museum

See also

References

• Dempsey, G Drysdale (1857). "Extracts from a Rudimentary Treatise on the Locomotive Engine". Broadsheet (reprinted from book) (Broad Gauge Society) (55): 24–26. 
• Kichenside, G.M. (1964). Railway Carriages, 1839-1939. London: Ian Allan. 
• Parkhouse, Niel; Pope, Ian. "The Rise and Fall of the Steam Rail Motor". Archive (Lightmoor Press) (3): 39–46. ISSN 1352-7991.  Cite uses deprecated parameters (help)
• Mountford, Eric R (1987). The Barry Railway, Diagrams and photographs of Locomotives, Coaches and Wagons. Oxford: Oakwood Press. 

External links

• History of GWR railmotors and autocoaches
• The GWR Steam Railmotor Project