Diesel locomotive were classified as DET 1 and DET 2 (). Due to shortage of petrol products during World War I, they remained unused for regular service in Germany. In 1922, they were sold to Swiss Compagnie du Chemin de fer Régional du Val-de-Travers (), where they were used in regular service up to the electrification of the line in 1944. Afterwards, the company kept them in service as boosters till 1965. Fiat claims a first Italian diesel–electric locomotive built in 1922, but little detail is available. A Fiat-TIBB diesel–locomotive "A", of 440CV, is reported to have entered service on the Ferrovie
TU2 diesel locomotive TU2 diesel locomotive TU2 (ТУ2) is a Soviet narrow gauge diesel locomotive for the track gauge of The decision to replace steam locomotives by diesel ones on the narrow gauge railways was taken after the Second World War. The first diesel locomotive built for the narrow gauge railways was the TU1, built in 1954; only two locomotives of this type were built. The TU2 was an improved redesign of the TU1. The first TU2 was built in 1955. The first TU2 was tested on the test site of the Central Scientific Institute (in Shatura), that belonged to the Ministry of