BR 13.10-12

With the four cylinder saturated steam locomotive (non superheated) of type S7, there were again steam engines who were able to cope with the superheated S4. The further development of the S4 was achieved through a contest, wrote out by the Vereins Deutscher Ingenieure (VDI). In this contest, they asked to design a locomotive which was able to pull a train of 180 ton on a flatland with a speed of 120 km/h. One of the entries was originated to Robert Garbe, who designed a 2'B h2 steam engine with driving wheels of 2200 mm diameter. They decided to carry out this design, only with driving wheels with a diameter of 2100 mm.

But because of an axle load of 16 ton there had to be a couple of weight saving measures to be taken. Because of that the locomotives did not completely satisfy the expectations. But when in 1910 the axle load of mainlines was rising to 17 ton, they could remove the weight saving measures. So the locomotive indicated as S6 was satisfying.

The S6 was the last big 2'B express train steam engine in Germany, and for a long time economical the best locomotive of the Prussian railways. Until 1913 there were built 584 steam engines of type S6.

The DRG took over 286 steam engines and gave them the indication BR 13.10-12 with the numbers: 13 1001 up to 13 1286. The locomotives were set aside in the twenties.