The Great Central Railway Class 8H (LNER Class S1) was a class of 0-8-4T

steam Steam is water vapor, often mixed with air or an aerosol of liquid water droplets. This may occur due to evaporation or due to boiling, where heat is applied until water reaches the enthalpy of vaporization. Saturated or superheated steam is inv ...

tank locomotive A tank locomotive is a steam locomotive which carries its water in one or more on-board water tanks, instead of a more traditional tender (rail), tender. Most tank engines also have Fuel bunker, bunkers (or fuel tanks) to hold fuel; in a #Tender ...

s designed by

John G. Robinson John George Robinson CBE, (30 July 1856 – 7 December 1943) was an English railway engineer, and was chief mechanical engineer of the Great Central Railway from 1900 to 1922. Early life Born at Newcastle upon Tyne, the second son of Matthew Robi ...

for

hump shunting A classification yard (American English, as well as the Canadian National Railway), marshalling yard (British, Hong Kong, Indian, and Australian English, and the former Canadian Pacific Railway) or shunting yard (Central Europe) is a railway y ...

at Wath marshalling yard.

Overview

Four locomotives were built in 1907/1908 for the

Great Central Railway The Great Central Railway in England was formed when the Manchester, Sheffield and Lincolnshire Railway changed its name in 1897, anticipating the opening in 1899 of its Great Central Main Line, London Extension. On 1 January 1923, the company ...

. They were fitted with three cylinders. This gave a more even

torque In physics and mechanics, torque is the rotational analogue of linear force. It is also referred to as the moment of force (also abbreviated to moment). The symbol for torque is typically \boldsymbol\tau, the lowercase Greek letter ''tau''. Wh ...

than with a 2-cylinder locomotive and reduced the risk of wheelslip under heavy load. All four passed into

London and North Eastern Railway The London and North Eastern Railway (LNER) was the second largest (after London, Midland and Scottish Railway, LMS) of the "Big Four (British railway companies), Big Four" railway companies created by the Railways Act 1921 in Britain. It ope ...

ownership at the 1923

grouping Grouping generally refers to the creation of one or more groups, or to the groups themselves. More specifically, grouping may refer to: * Shot grouping in shooting sports and other uses of firearms * the use of symbols of grouping in mathemati ...

. At the time all four locomotives were allocated to Mexborough engine shed. These were powerful locomotives but even more power was required so, in 1930, one locomotive was fitted with a

superheater A superheater is a device used to convert saturated steam or wet steam into superheated steam or dry steam. Superheated steam is used in steam turbines for electricity generation, in some steam engines, and in processes such as steam reforming. ...

and a

booster engine A locomotive booster for steam locomotives is a small supplementary two-cylinder steam engine back-gear-connected to the trailing truck axle on the locomotive or one of the trucks on the tender. It was invented in 1918 by Howard L. Ingersoll, ...

and classified S1/2. Two new locomotives (with superheaters and boosters) were built by the LNER in 1932 and classified S1/3. The remaining (non-booster) locomotives were classified S1/1 and were also fitted with superheaters. All the boosters were removed in 1943. All six locomotives passed into

British Railways British Railways (BR), which from 1965 traded as British Rail, was a state-owned company that operated most rail transport in Great Britain from 1948 to 1997. Originally a trading brand of the Railway Executive of the British Transport Commis ...

ownership in 1948 and were numbered 69900-69905.

Dimensions

* Locomotive weight: ** S1/1, 99 tons 6 cwt ** S1/2, 99 tons 2 cwt ** S1/3, 99 tons 1 cwt * Superheater: ** S1/1, No, but fitted later ** S1/2, Yes ** S1/3, Yes * Tractive effort, ** Booster tractive effort, *** Combined tractive effort, For terminology, see

Steam locomotive components __NOTOC__ Main components found on a typical steam locomotive include: File:Diagram_of_steam_locomotive_components_(March_2021_version).tif, center, 800px, The main components of a typical steam locomotive. Click or hover over numbers to see nam ...

References

* *

External links

LNER Encyclopedia
{{DEFAULTSORT:GCR Class 08H 08H 0-8-4T locomotives Railway locomotives introduced in 1907 Scrapped locomotives Standard-gauge steam locomotives of Great Britain Shunting locomotives