British Rail Class 50

This article includes a list of general references, but it lacks sufficient corresponding inline citations. Please help to improve this article by introducing more precise citations. (January 2014) (Learn how and when to remove this message)

English Electric Type 4 British Rail Class 50
A Class 50 at Birmingham New Street in 1987
Type and origin Power type Diesel-electric Builder English Electric at Vulcan Foundry Build date 1967–1968 Total produced 50
Specifications Configuration: ​  • UIC Co′Co′  • Commonwealth Co-Co Gauge 4 ft 8+1⁄2 in (1,435 mm) standard gauge Wheel diameter 3 ft 7 in (1.092 m) Wheelbase 56 ft 2 in (17.12 m) Length 68 ft 6 in (20.88 m) Width 8 ft 10 in (2.69 m) Height 12 ft 9 in (3.89 m) Axle load 19 long tons 10 hundredweight (19.8 t; 21.8 short tons) Loco weight 115 long tons (117 t; 129 short tons) Fuel capacity 1,540 imp gal (7,000 L; 1,850 US gal) Prime mover English Electric 16 CSVT Engine type 246 litres (15,000 cu in) Diesel engine Traction motors 6 English Electric type 538/5A axle-hung nose-suspended 400 hp (300 kW) traction motors Cylinders 16 MU working ■ Orange Square Train heating Electric Train Heat Train brakes Dual (Air and Vacuum)
Performance figures Maximum speed 100 mph (161 km/h) Power output Engine: 2,700 bhp (2,010 kW) Tractive effort Maximum: 48,500 lbf (216 kN) Continuous: 33,000 lbf (147,000 N)@ 23.5 mph (37.8 km/h)
Career Operators British Rail Numbers D400–D449; later 50001–50050 Nicknames Hoovers Axle load class Route availability 6 Withdrawn 1987–1994 18 preserved, remainder scrapped

The British Rail Class 50 is a class of diesel locomotives designed to haul express passenger trains at 100 mph (160 km/h). Built by English Electric at the Vulcan Foundry in Newton-le-Willows between 1967 and 1968, the Class 50s were initially on a 10-year lease from English Electric Leasing, and were employed hauling express passenger trains on the then non-electrified section of the West Coast Main Line between Crewe and Scotland. Initially numbered D400–D449 and known as English Electric Type 4s, the locomotives were purchased outright by British Rail (BR) at the end of the lease and became Class 50 in the TOPS renumbering of 1973.

The class gained the nickname "Hoovers" because of the noise made by the clean air plant at the No. 2 end, prior to refurbishment, which was likened to that of a vacuum cleaner, a name believed given to them by the staff at Paddington Station.^[1] Once the electrification from Crewe to Glasgow was completed the locomotives were moved to the Great Western Main Line (GWML) out of Paddington to allow the retirement of most of the remaining diesel-hydraulic locomotives then in use. As trains on the GWML steadily moved to High Speed Train operation from 1976, the Class 50s moved to hauling trains between London Waterloo and Exeter St Davids, and also trains from London Paddington to Hereford and Worcester via Oxford until the majority of those trains too were taken over by IC125 operation. The class was steadily retired from service in the late 1980s and early 1990s as their services moved to operation by second-generation Class 159 DMUs.