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
LMS diesel shunter 7052 LMS diesel shunter 7052 LMS diesel shunter 7052 was an experimental 0-6-0 diesel-mechanical shunting locomotive, introduced by the London Midland and Scottish Railway (LMSR) in 1934 and which remained in service with that railway for six years. It was later acquired for military use until 1966. No. 7052 locomotive was an experimental locomotive built by the Hunslet Engine Company at their Leeds works in 1934. It carried an original number of 7402 only within the works and was delivered as LMSR as number 7052. For six years it was used for shunting at Leeds before being loaned to the Air