In the thirties, the Turkish TCDD ordered two types of locomotives from German manufacturers which had many similarities to the German Einheitsloks. These were the 2-10-0 locomotives numbered from 56001 shown here and the 2-8-2 numbered from 46051. Both had a boiler similar to the DR class 41 and a Krauss-Helmholtz bogie that linked the leading axle to the first driving axle.
The first 79 locomotives had been built by several German manufacturers by 1941. 17 more went to the Bulgarian BDŽ and became class 12. Some were even shortly operated by the Reichsbahn during World War II and were designated class 5828. After the war, more locomotives were delivered by manufacturers from other countries. In 1948, Beyer, Peacock and Vulcan Foundry delivered 37. 50 more followed from Škoda and ČKD of Czechoslovakia. As late as in 1961, two more were built by Tülomsaş in Turkey.
Even though the Decapod wheel arrangement was mostly being used in freight service, the TCDD used them with all types of trains thanks to their Krauss-Helmholtz bogie. They even hauled the most important express trains and thanks to their low axle loading, they could also be used on secondary lines. The class could only be withdrawn after a sufficient number of the DE 24000 diesel locomotive was available. Today some are still existing, at least two still in working order.