Prussian P 6

Although the type designation suggests a purely passenger locomotive, the P 6 was developed as a mixed traffic locomotive. It was one of Robert Garbe's typical designs and played a role in the widespread use of superheated steam in Prussia.

The first example was completed by Hohenzollern in Düsseldorf in 1902 and had a driver diameter of just 1,500 mm so that it could also pull freight trains if necessary. In addition, a smoke box superheater was used in the early days. In the production version, the diameter of the drivers was increased by 100 mm, and the Schmidt-type smoke tube superheater was later used, as this had become established in the meantime. The certified top speed was 90 km/h, which was relatively high given the wheel diameter. 

In addition to the 30 engines from Hohenzollern, 111 were built at Schwartzkopff, 90 at Hanomag, 37 at Henschel, four in Karlsruhe and three at Linke-Hofmann, i.e. a total of 275 units. Six more were made for the Lübeck-Büchener Eisenbahn, these had slightly different dimensions. Production was discontinued in 1910 because the small diameter of the wheels and an incomplete mass balance had led to unfavorable running characteristics. These were so pronounced that the maximum speed could almost never be reached during operation, as the running was very unsteady. Instead, the slightly more powerful P 8 was produced in very large numbers, which subsequently became such a universal locomotive as the P 6 was originally intended to be.

After the First World War, a significant proportion of the existing 110 engines had to be passed abroad, the rest were later used by the Reichsbahn as class 37^0-1. After the end of World War II the locomotives were present in both parts of Germany, but due to the availability of newer and more powerful engines with better running smoothness all were retired and scrapped by 1950.