Kazimierz Zembrzuski, head of the design office in the First Polish Factory of Locomotives and at the same time professor of the Warsaw University of Technology.

The idea was to test both engines in parallel to compare top speed, acceleration, coal and water consumption etc.

After the German occupation of Poland during World War II, the two locomotives were renumbered into the Deutsche Reichsbahn (DRB) fleet as 18 601 and 18 602 (class 186).

The 18 602 survived the war, and was returned to Poland where it regained its PKP class and number.

In 1995, the machine went through a major overhaul and is now working in Wolsztyn as a tourist attraction, called Beautiful Helen (pl.