SNCF's CC 7100 class are part of a series of electric locomotives built by Alsthom. The prototype 'CC 7000' were built in 1949 and the production series locomotives CC 7101-CC 7158 followed during 1952–1955. Two of the class are notable for setting world rail speed records: CC 7121 reaching on 21 February 1954, and CC 7107 reaching on 28/29 March 1955.
History
The CC 7100 class were the first SNCFhigh-speed locomotives in which all the axles were motorized, i.e. with powered bogies rather a rigid frame. As delivered their top speed was. The CC 7100 were contemporaries of the 2D2 9100 for express passenger service on the PLM. From the outset it was apparent that bogie locomotives represented the future and so only a third of the anticipated 2D2s were built, in favour of the CC 7100.
Speed records
During the 1950s, SNCF's experimental investigations into high-speed rail saw some CC 7100 class locomotives specially-modified for operation at speeds far higher than their regular service speed. These experiments provided valuable test data for the SNCF to develop increasingly more rapid regular services, including the Mistral of 1967, and ultimately the TGV. CC 7121 broke the rail speed record when it achieved on the PLM mainline between Dijon and Beaune on 21 February 1954. Preparations for further high-speed tests proceeded, and in March 1955 CC 7107 and Bo-Bo locomotive BB 9004 both attained on separate high-speed runs between Bordeaux and Dax, Landes. CC 7107 hauled a three car train with streamlining modifications to reduce aerodynamic drag. Although the rail speed record has since 1990 been repeatedly broken by high-speed trainsets such as the French TGV and the GermanInterCityExperimental trains, BB 9004 and CC 7107 retained the locomotive speed record for over 50 years until it was broken on 2 September 2006 by a SiemensTaurus locomotive, ÖBB No 1216 050, which attained hauling a single dynamometer car on the Nuremberg-Munich high-speed rail line in Germany.
Later years
The locos were all given a "GRG" in the early 1980s to remove the original "skirts", and to replace the original windscreens and head/tail lamps clusters with "standard SNCF" arrangement. They replaced the 2D2 9100 in their last passenger service. Certain class members were fitted with third railpick up shoes to work Chambéry-Modane services. The shoes were removed in 1976. Despite their high-speed credentials, the CC 7100 class was relegated to freight haulage duties as more modern electric locomotives, commencing with the BB 9200 class, replaced them on passenger services.
Withdrawal and preservation
By 2001, the class was reduced to just five operating examples. The introduction of the BB 27000 classdual voltage freight locomotives led to the final withdrawal of these last locomotives from regular service. Together with fellow record holder BB 9004, CC 7107 was towed to Germany in 2006 to be present for No 1216 050's record breaking run.
