DR locomotive classification

The DR locomotive classification scheme in East Germany in the initial post-war period used the DRG system, consisting of a class number (Baureihennummer) followed by a serial number (Ordnungsnummer). With the introduction of computerised (EDP) numbers in 1970 as part of the UIC framework, the system was fundamentally changed for the first time.

In the allocation of operating numbers up to 1970 the Deutsche Bundesbahn and the Deutsche Reichsbahn in East Germany took care, for the most part, to ensure that they did not overlap with one another.

On 1 January 1950 almost all the public railways that did not belong to the Reichsbahn were nationalised. In order integrate the many, different locomotives into the existing numbering system, it was essential to adopt the renumbering plan of 12 December 1949 that built on the previous system.

The locomotives were grouped together into classes of the same or similar design. Locomotives were given the range of numbers from 5000 to 7000. However, the numbering was not consecutive, but was based on two technical aspects.

The first two figures gave the axle load in Mp. However, in order to ensure numbers fell within the allocated range, the number 50 had to be added. So, for example, locomotives with an axle load of 10 Mp were given the serial number 60.

The last two figures were based on whether the locomotive used saturated or superheated steam. Saturated steam locomotives were given the numbers 01 to 75 and superheated locomotives the numbers 76 to 99.

For narrow gauge locomotives with the class number 99 a similar scheme was chosen. Here, however, there were additional rules which were supposed to be followed when allocating the operating numbers (Betriebsnummer). Due to their complexity, these rules were not always adhered to. The first digit gave the rail gauge: 3 = 600 mm, 4 = 750 mm, 5 and 6 = 1,000 mm. The next digit indicated the axle load, with a '0' being used for 10 Mp and a '1' for 11 Mp. The last two digits indicated whether the engine was a tank locomotive (01 to 50) or a tender locomotive (from 51). The last steam locomotives in the Deutsche Reichsbahn were decommissioned in the 1980s.

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