Following on from the first article of our new “Sole Survivor” series, today we bring you the next instalment looking at the Great Western Railway (GWR) Churchward 4000 ‘Star’ Class steam locomotives. Once exploring the origins of the class, we will then into the preservation of No.4003 “Lode Star”, the Sole Survivor.
History of GWR Churchward 4000 ‘Star’ Class
For the first decade as Chief Mechanical Engineer (CME) of the GWR, Churchward conducted hundreds trials and tests to find the right layouts and dimensions for the various steam locomotive designs he had planned and build.
In 1904 and 1905 Churchward gained permission to buy three French 4-cylinder 4-4-2 compound locomotives, for testing against his own design and help develop them. The French engines had been trialled against his 2-cylinder 4-4-2 and 4-6-0 Simple engines, but Churchward now wanted to focuses on seeing if a simple engine could achieve the same efficiency as the French compounds, but not the high construction and maintenance costs.
In order to make the tests equal as possible, Churchward had a 4-cylinder 4-4-2 simple engine built in April 1906. Churchward was also impressed by the smooth riding of the French engines, a feature mainly caused by the 4-cylinder arrangement, another reason why he wanted to build a 4-cylinder engine.
Following on from successful tests and minor design changes to the prototype, the first series was ordered in 1907, all with the 4-6-0 wheel arrangement.
Lot 168 – Star series
The first batch of ten engines was built in 1907 to Lot 168. This series was numbered 4001 to 4010 and named after Stars, following on from the prototype locomotive, No.40 “North Star” (later No.4000). No.4010 “Western Star” received a superheated boiler with the Swindon No.1 superheater. After trialling and testing, Churchward settled on the Swindon No.3 variant, which the whole class eventually had fitted.
Lot 173 – Knight series
4011 to 4020 were constructed in 1908. 4011 “Knight of the Garter” also received a Swindon No.1 superheater from new and the whole batch had improved bogies (the design inspired by the French engine’s design).
Lot 178 – King series
Entering traffic in 1909, this batch (4021-30) was the first to feature ‘Holcroft Curves’ (curved ends to the frame) and No.4021 “King Edward” was fitted with a Swindon No.3 superheater. With the introduction of the 6000 ‘King’ Class in 1927, this batch was renamed after countries with Monarchs (4021 became “The British Monarch”). Later on, in 1940 many of the batch had their names removed due to World War 2.
Lot 180 – Queen series
Appearing in 1910 and 1911, all fitted with the Swindon No.3 superheater and the new style 3,500 Gallon tenders. 4031 to 4040 were named after British Queens.
Lot 195 – Prince series
Although only 5 (4041 to 4045) engines were built in this batch, they featured a number of improvements. These were slightly larger cylinder bore diameter (15 inches over 14 1/4in) producing a higher tractive effort and fitting of top feed, which would become standard on all GWR engines. The 5 engines were named after King George V’s sons.
Lot 199 – Princess series
A hike in long-distance passenger traffic leads to the Princess series, consisting of 15 engines. They featured all the Prince series improvements plus revised boiler design and improved four-cone vacuum ejector (needed on the long-distance passenger trains). They were numbered 4046 to 4060.
Lot 217 – Abbey series
The final batch was formed of 16 engines, named after Abbeys and numbered 4061 to 4072. They only had one improvement, and that was to the crank axles.
The basic dimensions and features of class, in Abbey series condition, include: 4-6-0 wheel arrangement (coupled wheels – 6 foot (ft) 8 1/2 inch (in), leading truck – 3ft 2in), Swindon No.1 boiler pressed at 225 lbf/in2, four cylinders (two inside and two outside) (15 in diameter and 26 in stroke) worked by Walschaerts valve gearing, total weight came in at 75.8 long tons (engine only) and a tractive effort of 27,800 lbf (GWR Power Class D, BR 5P).
Performance in Service
The Star class were used mainly on the long-distance express passenger trains, which they design was most suited to. They proved to be successful and reliable engines, working well into the 1950s. They could be seen across the whole of the GWR, from Paddington to South Wales.
Decline and Withdrawal
Churchward had plans to further modify the design by fitting the class with the larger Swindon No.7 Boiler, but with Collett becoming CME in 1922, he built the 4073 ‘Castle’ Class to his design based on the Stars, making them essentially a larger version of the Stars. Many Stars, in fact, were rebuilt as a Castle, usually, around the time major front end work was needed. Although the Stars were downgraded to the secondary route traffic in the 1920s, they still proved capable engines and many continued into the 1950s. The last engine to be withdrawn was No.4056 “Princess Margaret” in October 1957 aged 43.
1951 saw No.4003 “Lode Star” withdrawn and preserved. 4003 was the fourth member of the class built and covered just over 2 million miles between February 1907 and July 1951. On withdrawal, Lode Star was sent to Swindon Works to be prepared for use as a static display. Over the years the locomotive has been based at both STEAM museum in Swindon and National Railway Museum (NRM) York, spending a short stay at Tyseley for one of their open days. 4003 hasn’t run in the preservation and there are no plans to return the engine to steam in the foreseeable future. Currently based at NRM York.
For more information about 4003 “Lode Star”, please the National Railway Museum’s website here