The Schienenzeppelin or rail zeppelin was an experimental railcar which resembled the Zeppelin airship. It was designed by the German aircraft engineer Franz Kruckenberg in 1929. The Schienenzeppelin was powered by a propeller located at the rear. The railcar accelerated to 143 mph setting the land speed record for a petroleum powered rail vehicle. Only one Schienenzeppelin was ever built due to safety concerns. It was never really put into service and was finally dismantled in 1939. The propeller, which powered the railcar, was also the source of concern for its safety. It was exposed, and so the concern was that someone might be hit by he propeller.
Anticipating the design of the Schienenzeppelin, the earlier Aerowagon, an experimental Russian high-speed railcar, was also equipped with an aircraft engine and a propeller. On 24 July 1921, a group of delegates to the First Congress of the Profintern, led by Fyodor Sergeyev, took the Aerowagon from Moscow to the Tula collieries to test it. Abakovsky was also on board. Although they successfully arrived in Tula on their maiden run, the return route to Moscow was not successful. The Aerowagon derailed at high speed near Serpukhov, killing six of the 22 people on board. A seventh man later died of his injuries.
The Schienenzeppelin railcar was built at the beginning of 1930 in the Hannover-Leinhausen works of the German Imperial Railway Company. The work was completed by Fall of that year. The vehicle was 84 feet 9 3/4 inches long and had just two axles, with a wheelbase of 64 feet 3 5/8 inches. The height was 9 feet 2 1/4 inches. It had two conjoined BMW IV 6-cylinder petroleum aircraft engines. The driveshaft was raised seven-degrees above the horizontal to give the vehicle some downwards thrust. The body of the Schienenzeppelin was streamlined, having some 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. Its interior was designed in Bauhaus-style.
On May 10, 1931, the Schienenzeppelin exceeded a speed of 120 miles per hour for the first time. Afterwards, it toured Germany as an exhibit to the general public throughout Germany. There was still some concern due to the trains speed. On June 21, 1931, it set a new world railway speed record of 143 miles per hour on the Berlin–Hamburg line between Karstädt and Dergenthin, which was not surpassed by any other rail vehicle until 1954. The railcar still holds the land speed record for a petroleum powered rail vehicle. This high speed was attributable, in addition to other things, to its low weight, which was only 44800 pounds.
While several modifications were attempted, ultimately the Schienenzeppelin was scrapped. Due to many problems with the Schienenzeppelin prototype, the Deutsche Reichsbahn-Gesellschaft decided to go their own way in developing a high-speed railcar, leading to the Fliegender Hamburger (Flying Hamburger) in 1933. This new design was much more suitable for regular service and served also as the basis for later railcar developments. However, many of the Kruckenberg ideas were based on the experiments with Schienenzeppelin and high-speed rail travel, found their way into later DRG railcar designs.
The failure, if it could be called that, of Schienenzeppelin has been attributed to everything from the dangers of using an open propeller in crowded railway stations to fierce competition between Kruckenberg’s company and the Deutsche Reichsbahn’s separate efforts to build high-speed railcars. Another disadvantage of the rail zeppelin was the inability to pull additional wagons to form a train, because of its construction. Furthermore, the vehicle could not use its propeller to climb steep gradients, as the flow would separate when full power was applied. Thus an additional means of propulsion was needed for such circumstances. 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 close to passengers.