British Rail Class 23

English Electric Type 2 British Rail Class 23
“Baby Deltic” D5901 with the revised cab front.
Type and origin Power type Diesel-electric Builder English Electric at Vulcan Foundry Build date 1959 Total produced 10
Specifications Configuration: ​  • Whyte Bo-Bo  • UIC Bo'Bo' Gauge 4 ft 8 1⁄2 in (1,435 mm) standard gauge Wheel diameter 3 ft 7 in (1.092 m) Minimum curve 4 chains (80 m) Wheelbase 40 ft 6 in (12.34 m) Length 52 ft 6 in (16.00 m) Width 8 ft 10+3⁄4 in (2.71 m) Height 12 ft 8 in (3.86 m) Loco weight 74 long tons (75.2 t) Fuel capacity 550 imp gal (2,500 L; 660 US gal) Prime mover Napier T9-29 Deltic Transmission DC generator, DC traction motors MU working ★ Blue star Train heating Steam generator Train brakes Vacuum
Performance figures Top speed 75 mph (121 km/h) Power output Engine: 1,100 hp (820 kW) Tractive effort Maximum: 47,000 lbf (209.1 kN)
Career Railroad(s) British Railways Number D5900–D5909 Nicknames Baby Deltic Axle load class Route availability

British Rail Class 23, originally called English Electric Type 2, was a class of ten diesel-electric locomotives built by the English Electric Company in 1959. They were numbered from D5900 to D5909. The power unit was a Napier Deltic T9-29 9 cylinder engine of 1,100 bhp. This drove an EE generator, which powered the four traction motors. The Class 23 was nicknamed "Baby Deltic" because of its similarity to the Class 55.