Several times every year, the operational historic locomotives of SBB Historic in Olten are showed during "fitness runs" for preventing standstill damages. Here we can see Ae 3/6 II # 10439. The First World War caused a coal shortage in Europe, which is why SBB had to introduce a reduced wartime timetable, among other things. As a result, it was decided to electrify the SBB network quickly. Of course, suitable locomotives were needed, which is why SBB ordered four prototypes from the industry in 1917. The specifications for the final order included the following requirements:
Transport of 480 tons of trailer load on a 2 ‰ gradient at 90 km/h, as well as a 10 ‰ gradient at 65 km/h
3 round trips Zurich - St. Gallen with 480 tons trailer load within 10 hours
Start-up with 480 tons of trailer load on a 10 ‰ gradient and subsequent acceleration to 55 km/h within 4 minutes.
In the end, a total of 60 Ae 3/6 II locomotives were ordered in several tranches. Delivery took place between 1923 and 1926, although some locomotives initially had to be parked as the electrification of the network did not progress as quickly as new locomotives were delivered. Due to the good running characteristics, the maximum speed was increased from 90 km/h to 100 km/h in 1929. The locomotives were used throughout Switzerland, with the exception of western Switzerland. The first was decommissioned in 1965, followed by the last in 1977.
History of locomotive # 10439:
In 1976, the then SBB District II began looking for an Ae 3/6 II that could be restored as a historic locomotive. They finally decided on locomotive # 10439 and transferred it to the main workshop in Yverdon to prepare it for life as a historic locomotive. At the same time, locomotive no. 10452, which was to be refurbished as a heating locomotive but was technically in a much better condition than no. 10439, was also in Yverdon. The main workshop suggested swapping the two locomotives and preserving the technically better one historically. However, the Olten depot inspectorate insisted on retaining locomotive # 10439, as the other was not a "real" Olten locomotive (10439 spent its career in Olten, with a few brief exceptions; 10452 was only based in Olten for a short time before being decommissioned). In Yverdon, however, mainly parts of locomotive # 10452 were used (especially the locomotive frame and body) and the locomotive was finally converted to # 10439. The work of the people in Yverdon was so good that the operation went unnoticed for a long time except by the insiders.
