The Deutsche Reichsbahn's Class 52 is a German steam locomotive built in large numbers during the Second World War. It was the most produced type of the so-called Kriegslokomotiven or Kriegsloks (war locomotives). The Class 52 was a wartime development of the pre-war DRG Class 50, using fewer parts and less expensive materials to speed production. They were designed by Richard Wagner who was Chief Engineer of the Central Design Office at the Locomotive Standards Bureau of the DRG. About a dozen classes of locomotive were referred to as Kriegslokomotiven; however, the three main classes were the Class 52, 50 and 42. They were numbered 52 1-52 7794. A total of 20 are preserved in Germany. Many locomotives passed into Russian ownership after the Second World War. In the USSR, the class were designated TE (TЭ). Other operators of the type included Poland, Romania, Bulgaria, Norway and Turkey, among others. Design The Class 52 was a simplified version of the prewar Reichsbahn class 50 locomotive (produced 1938–1942). The simplified design of the class 52 was intended to reduce the man-hours and skills needed to manufacture it and to adapt to wartime shortages of strategic materials. Additional design changes gave the locomotives and their crew better protection against the cold. Between 1942 and the end of the war in May 1945, over 6,300 Class 52 locomotives were built. Additional locomotives were built post-war, giving a class total of probably 6719 units, delivered by seventeen manufacturers. The Class 42 was a larger version of the Class 52, but was produced in smaller numbers. Wagner had wanted locomotives which were long-lasting and easy to maintain, and unlike British engineers did not consider a high power-to-weight ratio a priority. The resulting Kriegslokomotive had a low axleload of and could haul 40 percent more freight than the old Prussian locomotives they replaced. The Class 52 could haul at without significant strain. On a 3% grade they could haul 800 tons at 5 km/h. Manufacture Over 7,794 locomotives of DRB Class 52 type were built across Europe for use on the Eastern Front during the Second World War. Thus it was one of the most numerous steam locomotives in the world. To achieve such numbers, the German locomotive manufacturers were merged into the 'Community of Greater German Locomotive Manufacturers', Gemeinschaft Grossdeutscher Lokomotivhersteller (GGL), which was a subdivision of the 'Rail Vehicles Main Committee', Hauptausschuss Schienenfahrzeuge (HAS)