Automatische Übersetzung. Originaltext in: EN - Original anzeigen As S 6 and P 8 steam locomotives were unable to provide a suitable solution for express services, especially on lines with higher gradients, the railroad management in particular at Kassel, Elberfeld, Frankfurt and Erfurt demanded with increasing urgency a new express locomotive with six driving wheels.

Initially, Robert Garbe, at the head of the Prussian department for locomotive purchasing, intended to upgrade the P 8 design with larger driving wheels (1'980 mm compared with original 1'750 mm) and a larger boiler and heating surface. On the other hand, superheated steam compound locomotives put into service by other railroad companies at the time showed outstanding results.

A compromise was finally agreed on a 4-6-0 superheated steam locomotive with four cylinders without compound effect.

The Berlin Mechanical Engineering company (BMAG) received in 1909 a contract to build 2x test units.

Automatische Übersetzung. Originaltext in: EN - Original anzeigen In the spring of 1910, the Berlin Mechanical Engineering company (BMAG) delivered the 2x prototypes, initially assigned as road numbers S 8 801 and 802 to the Erfurt district.

The similarities to the P 8 series were unmistakable. For ostensibly better access to the running gear components, the frame remained faithful to partially riveted and partially bolted prefabricated construction. The boiler of the P 8 design was used with a larger firebox and a larger outer firebox as well as a longer boiler. This allowed the evaporative heating surface to be increased from 143 to 154.3 square meters. The P 8 also contributed the large cab and you could almost be of the opinion that the running boards also had their origin here too.

The "low" construction of this design required wheel wells over the first driving wheels.

Automatische Übersetzung. Originaltext in: EN - Original anzeigen Soon after being delivered, road number S 8 Erfurt 802 was presented at the Brussels World Exhibition on April 23rd, 1910 to amazed experts. Yet presumably, this Prussian "Frugal Variation" ultimately led a rather shadowy existence among the locomotives exhibited because Pacific express locomotives with compound drive (4-6-2) had already been running in Europe for three years. The stars of the exhibition were if anything the Bavarian S 3/6 and three Pacific locomotives from the French railroads.

Even before the end of the exhibition on December 7th, road number 802 returned to its base in Gefilde and underwent extensive test runs. In the meantime, road number 801 had also been tested under normal operating conditions.

Automatische Übersetzung. Originaltext in: EN - Original anzeigen Overall, these two prototypes did not meet expectations whereby the insufficient boiler performance as well as the extremely difficult access to the internal running gear contributed negatively to the results.

After slight improvements, the first 10x S 10 units of the first regular production are delivered by the Berlin Mechanical Engineering company (BMAG) in 1911.