EMD Class 66
co-Co diesel locomotive

The Electro-Motive Diesel (EMD) Class 66 (EMD JT42CWR) are Co-Co diesel locomotives built by EMD for the European heavy freight market. Designed for use in Great Britain as the British Rail Class 66, a development of the Class 59, they have been adapted and certified for use in other European countries. Outside Europe, 40 locomotives have been sold to Egyptian Railways for passenger operation.
A number of locomotives built for Euro Cargo Rail in France with roof-mounted air conditioning are classed Class 77. In Germany ECR units operated for DB Schenker were numbered as class 247, re-classified as class 266 by the Eisenbahn-Bundesamt to match other Class 66 locomotives operating in Germany.
History
United Kingdom
The class was designed by General Motors-Electro Motive Division for use in the UK, and 250 were sold to English Welsh & Scottish, with orders from Direct Rail Services, Fastline, Freightliner and GB Railfreight.
Mainland Europe
With the locomotives proving successful in the UK, interest came from railway operators in continental Europe. General Motors locomotives in mainland Europe had historically been produced under license by local manufacturers. The high haulage capacity and reliability of the Class 59 (JT26-CW-SS) had led to its use by the German company Häfen und Güterverkehr Köln (HGK). The first mainland Europe order also came from HGK, for two locomotives, followed by TGOJ Trafik (Trafikaktiebolaget Grängesberg-Oxelösunds Järnvägar) in Sweden.
“EMD Class 66” enters the record as co-Co diesel locomotive. Crown Archives preserves that source wording while asking what Class, co-Co and diesel can confirm, complicate or overturn.
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This entry incorporates text from “EMD Class 66” 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.