GWR 4900 Class

GWR 4900 Class
Type and origin
Power typeSteam
DesignerCharles Collett
BuilderGWR Swindon Works
Order numberLots 254, 268, 275, 281, 290, 297, 304, 311, 327, 333, 338, 340
Build date1928–1943
Total produced258
RebuilderGWR Swindon Works
Rebuild date1924
Number rebuilt1 (4900 Saint Martin)
Specifications
Configuration:
 • Whyte4-6-0
 • UIC2′C h2
Gauge4 ft 8+12 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 curve8 chains (528 ft; 161 m) normal,
7 chains (462 ft; 141 m) slow
Length63 ft 0+14 in (19.21 m) over buffers
Width8 ft 11+14 in (2.724 m)
Height13 ft 3+14 in (4.045 m)
Axle load18 long tons 19 cwt (42,400 lb or 19.3 t)
(21.2 short tons)
Adhesive weight57 long tons 0 cwt (127,700 lb or 57.9 t)
(63.8 short tons)
Loco weight75 long tons 0 cwt (168,000 lb or 76.2 t)
(84.0 short tons)
Tender weight46 long tons 14 cwt (104,600 lb or 47.4 t)
(52.3 short tons)
Fuel typeCoal
Fuel capacityChurchward tender: 7 long tons (7.1 t; 7.8 short tons)
Collett/Hawksworth tender: 6 long tons (6.1 t; 6.7 short tons)
Water cap.Churchward tender: 3,500 imp gal (16,000 L; 4,200 US gal)
Collett/Hawksworth tender: 4,000 imp gal (18,000 L; 4,800 US gal)
Firebox:
 • Grate area27.07 sq ft (2.515 m2)
BoilerGWR Standard No. 1
Boiler pressure225 lbf/in2 (1,550 kPa; 15.8 kgf/cm2)
Heating surface:
 • Firebox154.78 sq ft (14.380 m2)
 • Tubes and flues1,686.60 sq ft (156.690 m2)
Superheater:
 • Heating area262.62 sq ft (24.398 m2)
CylindersTwo, outside
Cylinder size18.5 in × 30 in (470 mm × 762 mm)
Performance figures
Tractive effort27,275 lbf (121.33 kN)
Career
OperatorsGWR » BR
Power classGWR: D,
BR: 5MT
Numbers4900–4999, 5900–5999, 6900–6958
Official nameHall
Axle load classGWR: Red
Withdrawn1941 (4911 Bowden Hall, was destroyed beyond repair during a bombing raid and then cut up), 1959–1965 (remainder)
Preserved4920, 4930, 4936, 4942, 4953, 4965, 4979, 5900, 5952, 5967, 5972
DispositionTen preserved or extant (two operational as of March 2021),
one rebuilt as Saint class,
remainder scrapped

The Great Western Railway 4900 Class or Hall Class is a class of 4-6-0 mixed-traffic steam locomotives designed by Charles Collett for the Great Western Railway. A total of 259 were built at Swindon Works, 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.