British Rail Class 28

Specifications
Specifications
Configuration:;
• UIC	Co'Bo'
• Commonwealth	Co-Bo
Gauge	4 ft 8+1⁄2 in (1,435 mm) standard gauge
Wheel diameter	3 ft 3+1⁄2 in (1.003 m)
Minimum curve	3.5 chains (70 m)
Wheelbase	42 ft 9 in (13.03 m)
Length	56 ft 7+1⁄2 in (17.26 m)
Width	8 ft 6 in (2.59 m)
Height	12 ft 1+1⁄2 in (3.70 m)
Loco weight	97 long tons (98.6 t; 109 short tons)
Fuel capacity	510 imp gal (2,300 L; 610 US gal)
Prime mover	Crossley HST V8
Generator	DC
Traction motors	5 × Metropolitan-Vickers 137BZ, DC
Transmission	Diesel electric
MU working	● Red Circle
Train heating	Spanner steam generator of 1,500 lb/h (680 kg/h)
Train brakes	Vacuum

Type and origin
Type and origin
Power type	Diesel-electric
Builder	Metropolitan-Vickers’ Bowesfield Works, Stockton-on-Tees.
Build date	1958–1959
Total produced	20

Metropolitan Vickers Type 2,
British Rail Class 28
Metropolitan Vickers Type 2, ; British Rail Class 28
	Two 'Metrovicks' Nos. D5703 & D5710 passing Millbrook, Bedfordshire in 1960
Power type
Type and origin
Power type	Diesel-electric
Builder	Metropolitan-Vickers’ Bowesfield Works, Stockton-on-Tees.
Build date	1958–1959
Total produced	20
Configuration:;
Specifications
Configuration:;
• UIC	Co'Bo'
• Commonwealth	Co-Bo
Gauge	4 ft 8+1⁄2 in (1,435 mm) standard gauge
Wheel diameter	3 ft 3+1⁄2 in (1.003 m)
Minimum curve	3.5 chains (70 m)
Wheelbase	42 ft 9 in (13.03 m)
Length	56 ft 7+1⁄2 in (17.26 m)
Width	8 ft 6 in (2.59 m)
Height	12 ft 1+1⁄2 in (3.70 m)
Loco weight	97 long tons (98.6 t; 109 short tons)
Fuel capacity	510 imp gal (2,300 L; 610 US gal)
Prime mover	Crossley HST V8
Generator	DC
Traction motors	5 × Metropolitan-Vickers 137BZ, DC
Transmission	Diesel electric
MU working	● Red Circle
Train heating	Spanner steam generator of 1,500 lb/h (680 kg/h)
Train brakes	Vacuum
Maximum speed
Performance figures
Maximum speed	75 mph (121 km/h)
Power output	Engine: 1,200 hp (895 kW)
Tractive effort	Maximum: 50,000 lbf (222 kN)
Operators
Career
Operators	British Railways
Numbers	D5700–D5719
Axle load class	Route availability 6
Retired	December 1967 – September 1968
Disposition	One preserved, remainder scrapped

The British Rail Class 28 (Metro-Vick Type 2) diesel-electric locomotives, known variously as 'Metrovicks', 'Crossleys' or 'Co-Bos', were built under the Pilot Scheme for diesel locomotives as part of the British Railways 1955 Modernisation Plan.

These Crossley-engined locomotives were one of two designs built under the Pilot Scheme to use two-stroke diesel engines, the other being the Class 23 'Baby Deltic' locomotives.

The locomotives had a Co-Bo wheel arrangement (a 6-wheel bogie at one end, a 4-wheel bogie at the other) – unique in British Railways practice and uncommon in other countries, although Japan also used some C-B diesel hydraulics. The maximum tractive effort of 50,000 lbf (220 kN) was unusually high for a Type 2 locomotive but, as there were five (not four) driving axles, the risk of wheelslip was minimal.