BR 4-6-0 ‘British Monarch’ 4000 Star Class - Early BR
The first Star Class locomotive 'North Star', originally number 40, was introduced in 1906 as an experimental locomotive. It was constructed with a 4-4-2 wheel arrangement for comparative trials with 4-cylinder compound locomotives of the de Glehn type which had been obtained from France. This established the benefits of the balanced 4-cylinder layout, but the designer, George Jackson Churchward, Chief Mechanical Engineer (CME) of the Great Western Railway (GWR) decided that he would continue the Class with simple steam expansion, and the 4-6-0 wheel arrangement he had introduced with the 2900 Class.
Designed for express passenger services, a total of 73 of the Class were built in 10 batches between 1907 and 1923 at the GWR Swindon Works. They were numbered from 4000 to 4072.
The 4-cylinder locomotive had Walschaerts valve gear with rocking shafts, a boiler pressure of 225lb/sq in Su and driving wheels of 6' 81/2". The locomotive weighed 75tons and 12cwt and the tender 46tons 14cwt.
The early built locomotives were refitted with new boilers, outside steam pipes and were superheated, while the later locomotives were built this way. Under British Railways ownership the power classification changed from D to 5P.
Their appearance changed little during their long years in traffic and they regularly worked the heavy express train services, with some of the locomotives logging over two million miles during their lifetime. Most of the Class were fitted with 4,000 gallon high sided tenders after 1938, except two which ran with Hawksworth flat sided alternatives.
Five Stars were rebuilt as Castle Class locomotives in the mid-1920s and numbers 4063 - 4072 were renewed as Castle Class between 1937 and 1940 and renumbered as 5083 - 5092 respectively.
The first of the Class to be withdrawn was No. 4016 'The Somerset Light Infantry' (Prince Albert's) from Old Oak Common shed in October 1925. Fifteen others were withdrawn by GWR but 47 were passed to the newly formed British Railways in 1948 and remained in service until the last No. 4056 'Princess Margaret' was withdrawn in 1957.
Only one of the Class, No. 4003 'Lode Star' which was withdrawn in July 1951 has been preserved. It was overhauled and repainted at the Swindon Works. 'Lode Star' is on loan from the NRM and is a non-working static exhibit at the Steam Museum of the GWR, Swindon.
The locomotive represented here, No. 4021 'British Monarch', was outshopped on the 30th June 1909 and withdrawn from Shed 81F Oxford on the 31st October 1952 and was later that year cut up.
Suitable rolling stock: R4644, R4642