Kammback

A Kammback is a car body style that derives from the research of the German aerodynamicist Wunibald Kamm in the 1930s. The design calls for a body with smooth contours that continues to a tail that is abruptly cut off. This shape reduces the drag of the vehicle.

"Kammback" is an American term. In Europe the design is generally known as a Kamm tail or K-tail.

Paul Jaray experimented and developed streamlined car body work in the 1920s. His innovative body design featuring a low-profile teardrop shape with a long tail minimized the air resistance of passenger cars. Better highway systems being built in the 1930s called for higher automobile cruising and top speeds, thus, automobile designers focused on the aerodynamic characteristics of cars.Wind tunnel tests showed that a true tear-drop shaped body offered only a slight improvement in efficiency to the Chrysler Airflow design. In 1935, Georg Hans Madelung, a German engineer, professor, and aircraft designer, showed that a vehicle does not need a long tapered tail at high speeds.

Freiherr Reinhard Koenig-Fachsenfeld "developed a body style whose tail was cut off to form a flat rear surface" to reduce the air turbulence caused by the apparently streamlined, but steeply raked roofs of cars that used Paul Jaray's principles. He worked on an aerodynamic design for a bus, and Koenig-Fachsenfeld patented the idea.

In 1936, "further research by the FKFS—Forschungsinstitut für Kraftfahrwesen und Fahrzeugmotoren Stuttgart (Stuttgart Research Institute for Automotive and Automobile Engine Technology), under the direction of Wunibald Kamm, proved that vehicles with the so-called K- or Kamm tail, following Koenig-Faschsenfeld's lead, offered a good compromise between everyday utility (e.g. vehicle length and interior dimensions) and an attractive drag coefficient". In addition to aerodynamic efficiency, Wunibald Kamm also emphasized vehicle stability in his design. He proved mathematically and empirically the effectiveness of the design. The Kamm-back, or K-form, was a body with a smoothly contoured front that continues to an abrupt vertical flat surface in the rear.

The earliest use of "Kamm" to describe an automobile body incorporating this design was the prototype 1940 'Kamm' Coupe based on a BMW 328 chassis. The earliest mass-produced cars that used Kammback principles were the 1949–1951 Nash Airflyte in the U.S. and the 1952–1955 Borgward Hansa 2400 in Europe.

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