Rumpler, born in Vienna, was known as a designer of aircraft when at the 1921 Berlin car show he introduced the Tropfenwagen.

The Rumpler was already wind tunnel optimized at the Aerodynamics Research Institute in Göttingen[1] and had a drag coefficient of only 0.28, a value that astonished later engineers when they tested the Tropfenwagen in the 1970s.

[7] The car featured a Siemens and Halske-built[8] 2,580 cc (157 cu in) overhead valve W6 engine, with three banks of paired cylinders, all working on a common crankshaft.

[9] Able to seat four or five,[11] all the passengers were carried between the axles for maximum comfort, while the driver was alone at the front, to maximize view.

[12] Later Auto Union racing cars resembled the Benz Tropfenwagen racers and were built in part by Rumpler engineers.

Sales were hindered by small problems at the start (cooling, steering), the appearance of the vehicle, and the absence of a luggage compartment.