The GWR 4073 Class or Castle class locomotives were a group of 4-6-0 steam locomotives of the Great Western Railway. In the Whyte notation, a 4-6-0 is a Railroad Steam locomotive that has a two-axle Leading truck followed by three Driving axles A steam locomotive is a Locomotive powered by Steam. The term usually refers to its use on Railways but can also refer to a "road locomotive" The Great Western Railway ( GWR) was a British railway company and a notable example of Civil engineering, linking London with the West They were originally designed by the railway's Chief Mechanical Engineer, Charles Collett, for working the company's express passenger trains. Charles Benjamin Collett ( September 10 1871 - April 5 1952) was Chief mechanical engineer of the Great Western Railway
A development of the earlier Star Class, one hundred and seventy-one (171) were built, over a 25 year span from August 1923 to August 1950. A Star class locomotive was a particular type of Steam locomotive of the Great Western Railway. Year 1923 ( MCMXXIII) was a Common year starting on Monday (link will display the full calendar of the Gregorian calendar. Year 1950 ( MCML) was a Common year starting on Sunday (link will display the full calendar of the Gregorian calendar. They were numbered 4073–4099; 5000–5099; 7000–7037.
Although most were built new, sixteen locos were rebuilt from older locomotives—fifteen Star Class locomotives; and the Great Western Railway's sole 4-6-2 locomotive, number 111 The Great Bear. A Star class locomotive was a particular type of Steam locomotive of the Great Western Railway. The Great Western Railway ( GWR) was a British railway company and a notable example of Civil engineering, linking London with the West Under the Whyte notation for the classification of Steam locomotives, a 4-6-2 Locomotive has four Leading wheels (generally arranged in a The Great Bear, number 111 was a locomotive of the Great Western Railway.
The Castle class was noted for superb performance on the Cheltenham Flyer during the 1930s: on June 6 1932, pulled by 5006 Tregenna Castle, the train covered 77 miles (124 km) from Swindon to Paddington at an average speed of 81. The Cheltenham Spa Express is a British named passenger train service from Paddington station, in London to Cheltenham Spa, in Gloucestershire Year 1932 ( MCMXXXII) was a Leap year starting on Friday of the Gregorian calendar. Swindon ( is a large town in the ceremonial county of Wiltshire in the South West of England, midway between Bristol (64 km / 40 miles Paddington is an area of the City of Westminster, in Central London, England. 68 miles per hour (131. 45 km/h). This world record for steam traction was widely regarded as an astonishing feat.
In 1926, number 5000 Launceston Castle was loaned to the London, Midland and Scottish Railway where it ran trials between London to Carlisle. London Midland for the new (2007 railway company The London Midland and Scottish Railway ( LMS) was a British Railway company Carlisle (pronounced CARLYLE(emphasis on the first syllable is a City in northern England the largest settlement in Cumbria. It was rumoured that LMS tried to persuade GWR to build a batch of Castles for use on the West Coast Main Line.
Withdrawal started in the 1950s; the last to be withdrawn was Clun Castle at the end of 1965. 7029 Clun Castle was built to the Great Western Railway Castle Class design by the Western Region of British Railways at Swindon Works in May
Cylinders: 4; 16 in (406 mm) diameter, 26 in (660 mm) stroke
Valve gear: inside cylinders – Walschaert's; outside cylinders – derived from inside cylinders via rocking bars. The Walschaerts valve gear is a type of Steam engine Valve gear invented by Belgian railway mechanical engineer Egide Walschaerts
Valves: piston valves
Boiler pressure: 225 lbf/in² (1. 55 MPa)
Driving wheel diameter: 6 ft 8. 5 in (2. 04 m)
Tractive Effort: 31,625 lbf (140. 675 kN)
Engine weight: 79 tons 17 cwt (81. 1 Mg)
Tender weight: 46 tons 14 cwt (47. This article is about the tonne or metric ton For other tons see Ton. 44 Mg)
Eight Castles survive in preservation:
|Number||Name||Current Location||Current Status|
|4073||Caerphilly Castle||Swindon Steam Railway Museum||On Static Display|
|4079||Pendennis Castle||Didcot Railway Centre||Under Overhaul|
|5029||Nunney Castle||Tyseley Locomotive Works||Operational, Main line Certified|
|5043||Earl of Mount Edgcumbe (Banbury Castle)||Tyseley Locomotive Works||Under Overhaul|
|5051||Earl Bathurst (Drysllwyn Castle)||Didcot Railway Centre||On Static Display|
|5080||Defiant (Ogmore Castle)||Buckinghamshire Railway Centre||On Static Display|
|7027||Thornbury Castle||The Railway Age Crewe||Stored Awaiting Restoration|
|7029||Clun Castle||Tyseley Locomotive Works||On Static display Awaiting Overhaul|
Collett & Hawksworth Locomotives—A Pictorial History, Brian Haresnape, Ian Allen Ltd, 1978, ISBN 0-7110-0869-8