DRG locomotive classification

The DRG locomotive classification system was developed by the German Imperial Railway Company or Deutsche Reichsbahn-Gesellschaft (DRG), which was formed in 1924 following the merger of the German state railways (Länderbahnen) in 1920. A common classification and numbering scheme was needed in order to organise effectively the four hundred or so different steam locomotive classes taken over from the state railways, as well as new locomotives. This process lasted until 1926. Only then was the final renumbering plan fixed.

Similar systems for electric and internal combustion engined locomotives and railbuses were not developed until the 1930s, as the numbers of these types of motive power continued to rise and the previous schemes proved no longer adequate.

This classification or numbering system was repeatedly adjusted, and was continued by the Deutsche Bundesbahn until 1968 and by the Deutsche Reichsbahn in East Germany until 1970. After that the two German railway administrations introduced new computerised vehicle numbers; nevertheless the new DB classification scheme and DR classification scheme were still based on that of the DRG. In addition to the class numbers, a secondary system of German locomotive types was developed that contained the most important operating parameters of the locomotives and which was usually displayed on the cab sides.

The basic numbering system for steam locomotives comprised a class number and a serial number. The class number had two digits, the serial number had three to four digits.

New locomotives procured by the DRG were allocated their own class number. Locomotives taken over from the state railways on the foundation of the DRG were grouped into overall classes according to wheel arrangement and role, with each sub-class (Gattung, the equivalent of a former state railway 'class') being allocated its own range of serial numbers within its class.

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