|Introduced||1903 – 1906 & 1929 – 1949|
|Designer||Churchward & Collett|
|Driving Wheels||5ft 8ins|
|Boiler Pressure||200psi superheated|
|Cylinders||Outside – 18in x 30in|
|Valve Gear||Stephenson (piston valve)|
The large Prairie tanks were all developed from a prototype built in 1903. This was No 99. It was later renumbered 3100 and thirty-nine others were built in 1905-1906 and numbered 3111-31149. This was the old 3100 class. In 1906-1908 forty-one engines were built with larger boilers which formed the 3150 class.
In 1929 the old 3100 class engines were renumbered in the 5100 series and they were known as the 5100 class. They had been superheated and were rebuilt by Collett with detail alterations and increased weight from 75t 10cwt to 78t 9cwt). 5100 and 5111-49 were therefore classed as 5100 class locomotives.
|3100 class – later called 5100 class|
|8100 class – 5100 class rebuild with 5ft 6in driving wheels|
From 1929 onwards new locomotives were built to the modified design and these were known as the 5101 class. The 6100 class locomotives introduced in 1931 were another variation with increased boiler pressure. Ten of the original 5100 class locomotives (including the original 5100) were rebuilt as the 8100 class in 1938-1939.
The 5100 and 5101 classes contained 180 locomotives (4100-4179 and 5100-5199).
|Year Built||BR Numbers||
The first locomotive to be withdrawn was 5149 in 1947, while others were still being built (4160-4179 appeared in 1948-1949). 149 were still in service at the start of 1948 when the railways were nationalised with the last 29 locomotives, which were all in the 4100-79 series, being taken out of service in 1965. The last two (4113 and 4161) were withdrawn in November 1965 whilst based at Worcester.
Apart from London, with only one example, the 5100 class engines were allocated to many depots throughout the Great Western system. They often became the mainstay of the suburban services, besides being employed to bank heavy trains uphill in Somerset, Devon and through the Severn Tunnel. They lasted until replaced by diesels from 1957 onwards.
These engines were particularly associated with the Birmingham commuter trains and were eventually surpassed by diesel multiple units. Perhaps the most prestigious service worked by the class was the Cheltenham Spa Express / Cheltenham Flyer with a 2-6-2T would work the service between Cheltenham and Gloucester where the train reversed and a ‘Castle’ was attached to the opposite end to take the service on to Paddington.
Accidents and Incidents
On 30th November 1948 4150 was running round its train at Lapworth having arrived there on a local train from Birmingham. 4150 was hit in thick fog by 5022 Wigmore Castle which had passed a signal set at danger whilst hauling a Paddington to Birkenhead train. Only minor injuries were suffered by crew members and passengers. 4150 had to have its entire front end rebuilt and new cylinders fitted at Swindon.