Completely new solutions in the railway industry appeared in 1920. Then, the first propeller-driven railway called the “Railplane” was constructed in Milngavie, Scotland. Unfortunately, the propellers mounted at the front and back of the vehicle had significant drags on curves. However, the experiments were continued and in 1923 in Germany engineer Franz Kruckenberg used propeller propulsion for his suspended monorail.
In 1931, Kruckenberg and engineer Stedelfeld patented the “Schienenzeppelin” – ground railway with propeller propulsion. The railcar was 26 metres long and weighed 18.5 tons. It is worth mentioning that the “Schienenzeppelin” reached a maximum speed of 143 mph (230 km/h), which was a record speed for many years. Tests involving railcars with propellers were also carried out in Glasgow in 1927 and in Los Angeles in 1931, but because of the high cost of track construction, difficulties on curves and the blasts caused by the propeller, the plans were abandoned.