Franz Kruckenberg's Schienenzeppelin.
On 21 June 1931 Franz Kruckenberg's Schienenzeppelin (set a new world railway speed record of 230.2 km/h (143.0 mph) on the Berlin line between Karstädt and Dergenthin, which was not surpassed by any other rail vehicle until 1954. The famous Schienenzeppelin was anticipated by the design of the Aerowagon an experimental high-speed railcar fitted with an aircraft engine and propeller traction. The railcar from germany was built in 1930 near Hannover by Franz Kruckenberg and finished in fall of the same year. It was about 15m long and had two axles. Originally, the railcar had two conjoined BMW petrol aircraft engines powering a four bladed propeller. The body of the Schienenzeppelin was streamlined, having a great resemblance to the era's popular Zeppelin airships and it was built of aluminum in aircraft style to reduce weight. The railcar could carry up to 40 passengers and its interior was designed in Bauhaus-style. On May 10 1931 the railcar reached speeds of 200 km/h for the first time and this achievement was reported across the German media immediately. The great success on June 21 was achieved with Kruckenberg steering the rail zeppelin himself and afterwards, the vehicle was displayed in Berlin. In 1932 Kruckenberg began a new project with the rail car involving significant modifications. It was given a completely new front end while the rear axle remained as it was. The aircraft engine was still used, but the power transmission was hydraulic through two Föttinger Fluid Drives for both directions of travel. Also, a pointed fairing was installed in place of the propeller. Kruckenberg completed this design in November 1932 During test drives in 1933 the new railway reached speeds of 180 km/h. Even though, Kruckenberg's designs never really went into 'mass' production, his designs found their way into later DRG railcar designs. His last version of the rail vehicle was produced in 1934 and it was sold to the Deutsche Reichsbahn (and dismantled in in order to re-use its material for military purposes. Unfortunately, the use of propellers in crowded railway stations was found too dangerous and due to its construction, it would have been difficult to pull additional wagons to form a train. Furthermore, Safety concerns have been associated with running high-speed railcars on old track network, with the inadvisability of reversing the vehicle, and with operating a propeller in close proximity to passengers. At yovisto, you may be interested in a historic video documentation on Kruckenberg's Schienenzeppelin.