Nez Cassé

The Nez Cassé series of locomotives is a large family of electric and diesel locomotives intended primarily for fast passenger service on the French SNCF railway system. Produced by Alsthom for use under multiple electrification networks and un-electrified lines, they have been in widespread use from the 1960s into the 21st century. Classes produced in the main series were BB 7200/7600 and CC 6500 under 1.5 kV DC, BB15000 under 25 kV 50 Hz AC, BB 22200 (7200+15000) and CC 21000 under dual 1.5 kV DC and 25 kV 50 Hz AC, and the diesel CC 72000/72100.

The locomotive series was developed from the 1964 quadruple-voltage CC 40100, designed by Paul Arzens, which was mainly used for Trans Europ Express international service. The CC 40100 featured a forward-leaning nose and windshield that drew comparisons with a broken-nose facial profile ("Nez Cassé"). A greater emphasis on crash protection for engine drivers in the following series added depth to the nose and changed the broken-nosed profile.

The first versions for the SNCF that were introduced in 1969, the 1.5kV CC 6500 and the 1.5/25kV CC 21000, used a Co'Co' bogie arrangement on account of their substantial weight. The unique BBB 8000 used by Korail from 1972 used a Bo'Bo'Bo' bogie arrangement due to track loading requirements and Korean rail geometry requirements. The later BB 7200, BB 15000 and BB 22200 were substantially lightened, and could use a Bo'Bo' arrangement. These later series, introduced by the SNCF from 1971–1976, were also less costly to procure.