British Rail Class D2/12

British Rail Class D2/12 was a locomotive commissioned by British Rail in England. It was a diesel powered locomotive in the pre-TOPS period built by Hudswell Clarke with a Gardner engine. The mechanical transmission, using a scoop control fluid coupling and four-speed Power-flow SSS (synchro-self-shifting) gearbox, was a Hudswell Clarke speciality.

British Railways class D2/12
Power type	Diesel-mechanical
Builder	Hudswell Clarke
Serial number	D1201–D1210
Build date	1961
Total production	10
Configuration	0-6-0 DM
Gauge
Wheel diameter	3 ft 6 in (1.067 m)
Locomotive weight	34.20 long tons (34.75 t)
Prime mover	Gardner 8L3
Transmission	Mechanical, Bostock & Bramley four-speed gearbox
Multiple working	Not fitted
Top speed	24 mph (39 km/h)
Power output	Engine: 204 bhp (152 kW)
Tractive effort	16,100 lbf (71.6 kN)
Train heating	None
Career	British Railways
Class	D2/12; later 2/14A; no TOPS class
Number	D2510–D2519
Axle load class	Route availability 4
Retired	1967
Disposition	6 scrapped, 4 sold NCB (3 scrapped, 1 preserved)