British Rail Class 01

British Rail Class 01

01002 inside the shed at Holyhead Breakwater. Withdrawn 01001 is just visible at the rear.

Type and origin Power type Diesel-mechanical Builder Andrew Barclay Sons & Co. Serial number 395–398, 424 Build date 1956 (4), 1958 (1) Total produced 5

Specifications Configuration: ​  • Whyte 0-4-0DM  • UIC B-dm Gauge 4 ft 8 1⁄2 in (1,435 mm) Wheel diameter 3 ft 2 in (0.965 m) Minimum curve 1.06 chains (21 m) normal 1.00 chain (20 m) dead slow Wheelbase 6 ft 0 in (1.829 m) Length 23 ft 8 in (7.214 m) Width 8 ft 5 1⁄2 in (2.578 m) Height 11 ft 10 1⁄2 in (3.620 m) Axle load 13 ft 6 in (4.115 m) Loco weight 25.05 long tons (25.5 t; 28.1 short tons) Fuel capacity 325 imp gal (1,480 l; 390 US gal) Prime mover Gardner 6L3 Engine RPM:  • Maximum RPM 1,200 Engine type 6-cylinder in-line Four-stroke diesel engine Transmission Mechanical: Wilson SE4, 4-speed epicyclic gear box, Vulcan-Sinclair type 23 rigid hydraulic coupling, to a Wiseman 15LGB reverse and final drive unit. Loco brake Straight Air Train brakes 11503–11506: none 18: Vacuum

Performance figures Maximum speed 14.25 mph (22.9 km/h) Power output Engine: 153 hp (114 kW) At rail: 102 hp (76 kW) Tractive effort: ​  • Continuous 12,750 lbf (56.7 kN) at 2.63 mph (4.23 km/h) Brakeforce 15 long tons-force (150 kN)

Career Operators British Railways Numbers 11503–11506, 81 (departmental) later D2953–D2956 later 01001–01002 Axle load class RA 1 Withdrawn 1966–1981 Preserved D2953, D2956 (1st) Disposition Two preserved, remainder scrapped

The British Rail Class 01 diesel locomotive was a short wheelbase 0-4-0 diesel-mechanical design intended for use in areas with tight curves and limited clearance.

Four examples were built by Andrew Barclay Sons & Co. of Kilmarnock (Scotland) in 1956. They were numbered 11503-11506, then D2953-2956, and two survived long enough to enter the BR TOPS system as 01 001 (D2954) and 01 002 (D2955). Their original depot allocation was to Stratford (30A). A fifth similar locomotive was built in 1958 for departmental stock (maintenance work). It was originally No. 81 but was renumbered D2956 in July 1967 after the original D2956 had been withdrawn.

The locomotives were very versatile, despite having only 153 horsepower (114 kW) available, and were small enough to operate on any railway on the BR standard gauge network — except for the small problem that they were limited to 14 ¹⁄₄ miles per hour (22.9 km/h). For a fleet of just five locomotives, they were also very reliable, although Stratford Docks, where they originally worked, was not noted for creating very hard labour.

01 001 and 01 002 survived in BR service because they were required to service the Holyhead Breakwater, being the only locomotives light enough for that track. 01 001 was not used after 1973 but was cannibalised for spare parts to keep its sister loco in service. 01 001 was withdrawn in 1979, and 01 002 followed in 1981. 01 002 had last run when the Breakwater Railway closed in July 1980 both locomotives were cut up on site still carrying their original livery of British Railways black with black-and-yellow "wasp stripe" warning ends and the original British Railways "unicycling lion" emblem; they were the last locomotives in BR service to do so.

Class 01 locomotives had a Gardner 6-cylinder in-line, 4-stroke 6L3 engine of 153 hp (114 kW) at 1,200 rpm connected to a Wilson SE4, 4-speed epicyclic gear box with a Vulcan-Sinclair type 23 rigid hydraulic coupling, and a Wiseman 15LGB reverse and final drive unit. The wheels were connected by coupling rods and driven by a jackshaft.