SNCF Class CC 21000

The SNCF Class CC 21000 was a class of electric locomotives built by Alsthom in 1969 and 1974 for the French railways SNCF, a dual voltage version of the CC 6500 that could work from both 1500 volt direct current and 25 kV 50 Hz alternating current. Initially allocated to Dijon, the first two, CC 21001 and CC 21002, were fitted with cab signalling so that they could run test trains on the new high speed lines. In 1977 Amtrak borrowed CC 21003, which Alstom rebuilt with a transformer and electrical components compatible with Amtrak's 25 Hz traction power, taller pantographs, American couplers and Amtrak's cab signaling, and tested it as X996 alongside a Swedish SJ Rc4 as a possible replacement for the aging Pennsylvania Railroad GG1 locomotives. Its suspension proved unsuitable for relatively rough American track, Amtrak favored the Rc4 design that became the basis of the EMD AEM-7, and X996 was returned to France. The class was rebuilt into CC 6500 locomotives numbered CC 6575 to CC 6578 in 1995 and 1996, and all were withdrawn by 2005.