CIÉ 121 Class
railway locomotive
The Córas Iompair Éireann 121 Class were diesel-electric locomotives manufactured by General Motors Electro-Motive Division. These locomotives were in regular service on the Irish railway network until 2002, with the last two remaining in service until early 2008.
History
The poor availability of the A and C class locomotives in the late 1950s together with the split of the cross-border Great Northern Railway in 1958 and the target to eliminate steam locomotives led CIÉ to urgently seek more diesel locomotives. Prior to 1961, almost all Irish diesel locomotives had been built in Great Britain, but CIÉ now turned to an American-style single cab road switcher design from General Motors. The 121 Class were manufactured from December 1960 to January 1961 and numbered B121 to B135 inclusive. The locomotives proved an immediate success, with low maintenance and high availability, and led to further orders from the same supplier starting with the 141 class.
The 121 Class were the first locomotives to be exported to Europe from EMD's plant at La Grange. The layout of the cab was quite different from the other CIÉ diesel models of the time, with the controls to the side of the driver, rather than the front. Due to reduced visibility when operating with the cab trailing, it was decided that these locomotives should only operate in a cab-leading formation. Later conversion for multiple-unit working allowed two 121 Class locomotives to be coupled hood-end to hood-end, removing the need to turn them around for their return journey.
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This entry incorporates text from “CIÉ 121 Class” 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.