Traduction automatique. Texte original en: EN - afficher l'original In the postwar period, the Swiss Federal Railways had to cope with an increasing volume of traffic and were looking to procure a new six-axle bogie locomotive, especially for the Gotthard line (at the time, freight traffic was handled by Ae 4/6, Ae 4/7 and Ce 6/8 electric locomotives but they were not powerful enough to ensure an efficient service on the mountainous railway line).

A consortium consisting of Swiss Locomotive and Machine Works - SLM and Brown, Boveri & Compagnie - BBC (later joined by Oerlikon Machine Factory - MFO), was awarded the contract for the construction of two prototypes in 1949. During the same period, the two companies were working on a locomotive for the French National Railway Company - SNCF to be used on the Savoyard network electrified at 20 kV / 50 Hz alternative current. The unit, delivered in 1950 and registered as CC 6051, served as a model for the mechanical part of the Ae 6/6 prototypes. / Sources: https://de.wikipedia.org/wiki/SBB_Ae_6/6