2.3 metre diameter driving wheels, was easily attained. In scheduled services the engine ran with a streamlined train, but only at speeds up to 160 km/h. The tapered water tanks gave both driver and fireman a good all-round view of the line and the streamlined shell, officially called a Blechmantel, covered the driving gear fully. At around 230,000 Reichsmarks the engine was clearly more expensive than initially suggested. But that included all the design changes. By comparison a production version of the DRG Class 03 cost about 200,000 Reichsmarks. On top of that was the cost of the four coaches, 446,800 Reichsmarks. Three years later, a three-coach express unit of the "Köln" type, in series production, cost 600,000 Reichsmarks, the one-off SVT 135 155 as much as a million Reichsmarks. Shortly after construction had begun on locomotive 61 001, a variant - number 61 002 - was planned, and built in 1939. Locomotive 61 002 was give a three-axle trailing bogie, a third cylinder and larger coal and water tanks, otherwise the design and the components were the same as her predecessor. It also had smoke deflectors above on the chimney, as were also fitted to the streamlined locomotives of DRG Classes 01.10 and 03.10. In May the first factory trial runs were carried out and the locomotive was transferred on 12 June 1939 to the locomotive depot (Bahnbetriebswerk) of Berlin-Grunewald. Vehicle designation and equipment The Henschel-Wegmann train comprised the following: Steam locomotive 61 001; a streamlined tank locomotive with a 4-6-4 configuration, inside cylinders and 2.30 metre high driving wheels. Permitted top speed: 175 km/h; A trailer car (SBC 4ü-35) with 24 seats in 2nd and 32 seats in 3rd class, as well as four rotating seats in the panorama section at the end; Two centre cars (SBC 4ü) with 12 seats in 2nd and 56 seats in 3rd class. A trailer car (SWRPwPost 4ü) with a compartment for sorting post and packages during the journey as well as a dining area with 23 seats. Externally the coaches resembled the express multiple units of those years. In order the achieve the desired speed, they were of light construction and were five to ten tonnes lighter than normal passenger coaches. The short-coupled coaches could only be separated in the workshop. To couple the locomotive and coaches Scharfenberg couplers were fitted that at the same time served to couple the brake