BRITISH RAIL CLASS 21

British Rail 'Class 21' was a class of 1000hp or 1100hp Bo-Bo diesel-electric locomotives built by North British Locomotive Company in Glasgow. They were very similar in appearance to the Class 22 diesel-hydraulics.

Contents

Description

Technical details

Sources

Description

Fifty-eight were built, nos D6100-D6157, and they were originally allocated to the Eastern Region for commuter services into London. Unfortunately, they proved to be extremely unreliable, and were quickly transferred to the Scottish Region for convenience of return to their manufacturer when warranty work was required. However, North British Loco closed down soon afterwards. In an attempt to improve reliability, 20 (D6100-03/06-08/12-14/16/19/21/23/24/29/30/33/34/37) were later re-engined with 1350hp Paxman engines to form Class 29. The remaining 38 locomotives retained their original MAN engines and were all withdrawn from service by the end of 1967. None have been preserved.
These locos should not be confused with the new Class 21s recently acquired by Euro Cargo Rail, the European division of EWS.

Technical details

★ Introduced: 1959

★ Weight: 72 tons 10 cwt

★ Engine:

★
★ D6100-D6137, NBL/MAN 1,000 bhp

★
★ D6138-D6157, NBL/MAN 1,100 bhp

★ Transmission: Electric, four GEC traction motors

★ Maximum tractive effort: 45,000 lb

★ Driving wheel diameter: 3ft 7in

★ Coupling code:

★
★ D6100-D6137, Red circle (electro-magnetic)

★
★ D6138-D6157, Blue star (electro-pneumatic)

★ Train heating: Steam generator

Sources

Ian Allan ABC of British Railways Locomotives, summer 1966 edition