British Rail Class 46

Derby Type 4 British Rail Class 46
A Class 46 at Exeter St Davids in 1976.
Type and origin Power type Diesel-electric Builder British Railways’ Derby Works Build date 1961–1963 Total produced 56
Specifications Configuration: ​  • UIC (1′Co)(Co1′)  • Commonwealth 1Co-Co1 Gauge 4 ft 8+1⁄2 in (1,435 mm) standard gauge Wheel diameter 3 ft 9 in (1.143 m) Minimum curve 3.5 chains (70 m) Wheelbase 59 ft 8 in (18.19 m) Length 67 ft 11 in (20.70 m) Width 8 ft 10+1⁄2 in (2.71 m) Height 12 ft 10 in (3.91 m) Loco weight 138 long tons (140 t; 155 short tons) Fuel capacity 790 imp gal (3,600 L; 950 US gal) Prime mover Sulzer 12LDA28-B Generator Brush Traction motors Brush MU working ★ Blue Star Train heating Steam Train brakes Vacuum
Performance figures Maximum speed 90 mph (145 km/h) Power output Engine: 2,500 bhp (1,864 kW) At rail: 1,962 hp (1,463 kW) Tractive effort Maximum: 55,000 lbf (245 kN) Brakeforce 63 long tons-force (628 kN)
Career Operators British Railways Numbers D138–D193; later 46 001–46 056 Nicknames ‘Peak’ Axle load class Route availability 7 Withdrawn 1977–1984 Disposition Three preserved, one wrecked in nuclear flask test already destined for scrap, remainder scrapped

The British Rail Class 46 is a class of diesel locomotive. They were built from 1961 to 1963 at British Railways' Derby Works and were initially numbered D138–D193. With the arrival of TOPS they were renumbered to Class 46. Along with the similar Class 44 and 45 locomotives, they became known as Peaks.

Fifty-six locomotives were built. The first was withdrawn in 1977 and all were withdrawn by the end of 1984.