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British Rail Class 44

class of 10 (1Co)(Co1) 2300hp diesel-electric locomotives

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General referenceInterpretive dossier study · Crown Archives visual atlas
Record originEnglish Wikipedia
Text licenseCC BY-SA 4.0
Source revisionJul 14, 2026
Entity authorityQ3306567
Source-derived summary

The British Rail Class 44 or Sulzer Type 4 diesel locomotives were built by British Railways' Derby Works between 1959 and 1960, intended for express passenger services. They were originally numbered D1-D10 and named after mountains in England and Wales, and, along with the similar Class 45 and 46 locomotives, they became known as Peaks.

Overview

In part inspired by LMS prototypes 10000 and 10001, and by Southern Railway 10201-10203, the Class 44 diesels were some of the first big diesels commissioned for the British Rail modernisation project and were the precursors to the Class 45 and Class 46 locomotives of similar design. They were originally designed to have a Co-Co wheel arrangement, but it proved impossible to keep below the 20 long tons (20,000 kg) axle loading limit imposed by the British Railways Civil Engineer. A 1-Co bogie design originally used on the Southern Railway 10201 was used instead.

Construction began in the summer of 1958, although the first example was not completed until April 1959. The ten locomotives were originally allocated to Camden motive power depot and used on the West Coast Main Line, although also often seen on the Midland Main Line. However, with the advent of large numbers of Class 45 locomotives the 10 Class 44 locomotives were transferred to Toton.

Powertrain

A 2,300 bhp Sulzer 12LDA28-A diesel engine drove a Crompton Parkinson GC426-A1 main generator which supplied power to six Crompton Parkinson C171-B1 traction motors. When initially put into service, the locomotives were fitted with multiple working.

Editorial summary

The public source identifies “British Rail Class 44” as class of 10 (1Co)(Co1) 2300hp diesel-electric locomotives. This brief keeps that definition visible, then builds a research path around British, Rail and Class.

Editorial reviewA concise reference frame for defining the subject, testing terminology and identifying the institution closest to the evidence. The current lead gives the account dated anchors—1959, 1960, 1958—that can be checked directly. The selected authority fields contribute no independent date. Its value is orientation rather than verdict, with British, Rail and Class providing the first useful test.
Editorial analysis

Why this record matters

A short description can identify a subject without explaining its stakes. For “British Rail Class 44”, the useful work is to connect “class of 10 (1Co)(Co1) 2300hp diesel-electric locomotives” to the records capable of establishing context and consequence.

Evidence profile

Vocabulary and entity names are the principal evidence signals here, because they determine the precision of every later search. The source revision retrieved here is dated Jul 14, 2026. The linked authority identifier is Q3306567. The Library of Congress control number is sh86008190. 1 of 1 selected statements include explicit references; 0 carry qualifiers and 0 use preferred rank. The first chronological checks are 1959, 1960 and 1958.

Critical limits

Overview language is designed for orientation and should not be treated as a substitute for the evidence cited beneath it. The source lead contains qualifying language; that uncertainty should survive quotation, summary and reuse. Authority statements aid reconciliation but still require their own references, qualifiers and ranks to be checked.

How to read it

Use the entry as an orientation point, then follow its citations and revision history. Names, dates and institutional relationships should be checked against the original record.

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Source & attribution

This entry incorporates text from British Rail Class 44” on English Wikipedia. Contributors are listed in the page history. Text is available under the Creative Commons Attribution-ShareAlike 4.0 License. Selected authority identifiers and statements are retrieved from Wikidata under CC0; their references and qualifiers remain part of the verification path.