GWR 4900 Class

GWR 4900 Class

Preserved 4953 Pitchford Hall
Type and origin
Power type Steam
Designer Charles Collett
Builder GWR Swindon Works
Build date 1928–1943
Total produced 259
Specifications
Configuration 4-6-0
UIC class 2'Ch
Gauge 4 ft 8 1⁄2 in (1,435 mm) standard gauge
Leading dia. 3 ft 0 in (0.914 m)
Driver dia. 6 ft 0 in (1.829 m)
Minimum curve 8 chains (530 ft; 160 m) normal,
7 chains (460 ft; 140 m) slow
Length 63 ft 0 1⁄4 in (19.21 m) over buffers
Width 8 ft 11 1⁄4 in (2.72 m)
Height 13 ft 3 1⁄4 in (4.04 m)
Axle load 18 long tons 19 cwt (42,400 lb or 19.3 t)
Adhesive weight 57 long tons 0 cwt (127,700 lb or 57.9 t)
Loco weight 75 long tons 0 cwt (168,000 lb or 76.2 t)
Tender weight 46 long tons 14 cwt (104,600 lb or 47.4 t)
Fuel type Coal
Water cap 3,500 imp gal (16,000 l; 4,200 US gal) - 4,000 imp gal (18,000 l; 4,800 US gal)
Firebox:
 • Firegrate area		 27.07 square feet (2.515 m2)
Boiler pressure 225 lbf/in2 (1,550 kPa; 15.8 kgf/cm2)
Heating surface:
 • Tubes and flues		 1,686.60 square feet (156.690 m2)
 • Firebox 154.78 square feet (14.380 m2)
Superheater:
 ​
 • Heating area 262.62 square feet (24.398 m2)
Cylinders Two, outside
Cylinder size 18.5 in × 30 in (470 mm × 762 mm)
Performance figures
Tractive effort 27,275 lbf (121,330 N)
Career
Operators GWR » BR
Power class GWR: D,
BR: 5MT
Numbers 4900–4999, 5900–5999, 6900–6958
Official name Hall
Axle load class GWR: Red
Withdrawn 1960–1965
Preserved 4920, 4930, 4936, 4942, 4953, 4965, 4979, 5900, 5952, 5967, 5972
Disposition Ten (was eleven) preserved or extant, remainder scrapped

The Great Western Railway (GWR) 4900 Class or Hall Class is a class of 4-6-0 mixed traffic steam locomotives designed by Charles Collett. A total of 259 were built, numbered 4900–4999, 5900–5999 and 6900–6958. The LMS Stanier Class 5 4-6-0 and LNER Thompson Class B1 both drew heavily on design features of the Hall Class. After nationalisation in 1948, British Railways gave them the power classification 5MT.

Background

By the end of 1923 the GWR was well served with express passenger locomotives of the Saint and Star classes and had recently introduced the Castle Class. However the mixed traffic 2-6-0 locomotives of the 4300 Class were beginning to struggle with the increasing loads. George Jackson Churchward had recognised this with the introduction of the 4700 class 2-8-0 with 5 ft 8 in (1.727 m) driving wheels, intended for express goods and relief passenger trains. However, Collett preferred the idea of a Saint Class with smaller wheels to undertake these duties as this would provide a leading bogie. He therefore rebuilt number 2925 Saint Martin with 6 ft (1.829 m) driving wheels.[1]

Prototype

The prototype of the new class was rebuilt in 1924 and the cylinders were realigned in relation to the driving axle and a more modern 'Castle'-type cab was fitted. Saint Martin emerged from Swindon in 1924 and embarked on three years of trials. During this period Collett introduced other modifications such a changing the pitch of the taper boiler and adding outside steam pipes.

Production

After extensive trials during 1925-1927, Collett was satisfied with the performance of his prototype, subject to minor amendments and placed an order for eighty more with Swindon works (Lot 254) in 1928. The prototype was renumbered 4900 in December 1928 and the new locomotives were numbered 4901-80 and appeared at regular intervals until February 1930.[2]They were named after English and Welsh country houses with 'Hall' in their titles and so became known as the 'Hall Class'.

They differed little from the prototype; the bogie wheel diameter had been reduced by two inches from 3 ft 2 in (0.965 m) to 3 ft 0 in (0.914 m) and the valve setting amended to give an increased travel of 7.5 in (191 mm). The overall weight of the locomotive had increased by 2 long tons 10 cwt (5,600 lb or 2.5 t) to 75 long tons 0 cwt (168,000 lb or 76.2 t) but a tractive effort of 27,275 lbf (121.33 kN) compared favourably with the 24,935 lbf (110.92 kN) of the 'Saint'. The original locomotives were built with Churchward 3,500 imp gal (16,000 l; 4,200 US gal) tenders but after 4958 Collett's larger 4,000 imp gal (18,000 l; 4,800 US gal) types became standard although a few later locomotives were fitted with smaller tenders if these were available as they entered service.[3]

The first fourteen examples were despatched to the arduous proving grounds of the Cornish main line. They were so successful here and elsewhere on the GWR system that by the time the first production batch had been completed a further twenty were on order (Lot 268, 4981-99 and 5900). Further orders followed throughout the 1930s and early 1940s. By 1935, 150 were in service and the 259th and last Hall, No. 6958 Oxburgh Hall, was delivered in 1943. Thereafter further deliveries were of the '6959 Modified Hall' class.

Performance

As indicated by their continuing production, the Hall class proved to be very successful in a variety of different roles, although barred from several cross-country and branch lines because of their red weight classification. According to Peter Herring, 'they were the first true mixed traffic locomotives, and as such precursors of the Stanier 'Black Five', Thompson B1 and BR Standard 5MT 4-6-0.'[4] (This may have been true as far as 4-6-0 types were concerned but there were several successful 2-6-0 ‘mixed traffic’ types on the GWR and other British railways before them,[5] - not least the GWR 4300 Class they were designed to replace. [6])

Modified Hall Class

Main article GWR 6959 Class

Although the GWR had been at the forefront of British locomotive development between 1900 and 1930, the 1930s saw a degree of complacency at Swindon reflected in the fact that the design had largely originated in the 1900s and had not fundamentally changed since the mid 1920s.[7] Collett was replaced by F.W. Hawksworth in 1941 who created a modified version of the design, known as the Modified Hall Class. These remained in production under British Railways until 1950, by which time there were a further seventy-one locomotives.

Accidents and incidents

Withdrawal

All but one of the original Collett Halls entered British Railways service in 1948, the exception being No. 4911 Bowden Hall. Official withdrawals began in 1959 with the prototype Saint Martin. Its accumulated mileage, both in its original form and rebuilt form, was a remarkable 2,092,500 miles. Further withdrawals of the production series took place during the 1960s and the class was extinct by 1965.

Preservation

By 1965 the last Hall had been withdrawn from the Western Region without a single one entering the National Collection. Eleven examples of the Hall class have survived to preservation, of which seven have run in preservation. One of the preserved engines no 4942 Maindy Hall is being "regressed" back to a GWR Saint Class. Of the Seven halls to run in preservation six have been operated on the mainline in preservation: 4930 Hagley Hall, 4936 Kinlet Hall, 4953 Pitchford Hall, 4965 Rood Ashton Hall, 5900 Hinderton Hall and 5972 Olton Hall. 5972 Olton Hall has gained fame as the locomotive used in the Harry Potter film series.

Currently 4936 Kinlet Hall & 4965 Rood Ashton Hall are mainline certified.

Number Name Image Built Withdrawn Base Status Notes
4920 Dumbleton Hall March 1929 December 1965 South Devon Railway Static display, awaiting overhaul.
4930 Hagley Hall May 1929 December 1963 Severn Valley Railway Undergoing overhaul.
4936 Kinlet Hall June 1929 January 1964 West Somerset Railway Operational, mainline certified.
4942 Maindy Hall July 1929 December 1963 Didcot Railway Centre Undergoing Reconfiguration Currently being 'regressed' back to a GWR Saint Class.
4953 Pitchford Hall August 1929 May 1963 Epping Ongar Railway. Undergoing Overhaul Boiler ticket expired August 2013
4965 Rood Ashton Hall November 1930 March 1962 Tyseley Locomotive Works. Operational, mainline certified. First Hall class to leave Woodham Brothers scrapyard, Barry
4979 Wootton Hall February 1930 December 1963 Ribble Steam Railway Undergoing Restoration. Owned by Furness Railway Trust and was moved to Preston on 27 October 2014. Undergoing restoration inside the FRT's shed with the tender being restored first and then the loco getting restored to working order.
5900 Hinderton Hall March 1931 December 1963 Didcot Railway Centre, Static display, awaiting overhaul.
5952 Cogan Hall December 1935 June 1964 Llangollen Railway, Spares Donor. Some parts being used for 6880 Betton Grange, but will hopefully be restored to working order.
5967 Bickmarsh Hall March 1937 June 1964 Northampton & Lamport Railway Undergoing restoration.
5972 Olton Hall April 1937 December 1963 Carnforth MPD, Static Display Famed for hauling the The Hogwarts Express in the Harry Potter films, carrying Hogwarts Castle nameplates. Mainline certification expired 29 August 2014. Currently on display at Warner Bros. Studios, Leavesden near Watford for a minimum of two years

References

  1. ↑ le Fleming, H.M. (November 1960) [1953]. White, D.E., ed. The Locomotives of the Great Western Railway, part eight: Modern Passenger Classes (2nd ed.). Kenilworth: RCTS. pp. H29.
  2. ↑ le Fleming, H.M. (November 1960) [1953]. White, D.E., ed. The Locomotives of the Great Western Railway, part eight: Modern Passenger Classes (2nd ed.). Kenilworth: RCTS. pp. H29.
  3. ↑ le Fleming, H.M. (November 1960) [1953]. White, D.E., ed. The Locomotives of the Great Western Railway, part eight: Modern Passenger Classes (2nd ed.). Kenilworth: RCTS. pp. H30.
  4. ↑ Herring, Peter (2004). Classic British Steam Locomotives. Wigston: Abbeydale Press. p. 118. ISBN 1 86147 138 6.
  5. ↑ Casserley, H.C. (1960). The Historic Locomotive Pocket Book. London: Batsford. p. 217, 222.
  6. ↑ Casserley, H.C. (1961). Locomotives of British Railways. London: Spring Books. p. 28.
  7. ↑ Herring (2004), p.158.
  8. ↑ Riley, R.C. (1966). Great Western Album. Shepperton: Ian Allan. p. 90. ISBN 0 7110 0073 5.
  9. ↑ Bryan, Tim (1995). The Great Western at War 1939-1945 (1 ed.). Yeovil, Somerset, UK: Patrick Stephens. p. 94. ISBN 1-85260-479-4. OCLC 60238810.
  10. ↑ Stewart-David, David; Wood, Peter (2 July 2014). "The role of railways in the Second World War". The Railway Magazine (Horncastle, Lincs, UK: Mortons Media) 160 (1,360): 50. ISSN 0033-8923.
  11. ↑ Earnshaw, Alan (1991). Trains in Trouble: Vol. 7. Penryn: Atlantic Books. p. 39. ISBN 0-906899-50-8.
  12. ↑ Earnshaw, Alan (1993). Trains in Trouble: Vol. 8. Penryn: Atlantic Books. pp. Front cover, 3. ISBN 0-906899-52-4.

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