April 26, 1893|
|Died||October 11, 1966
|Awards||Automotive Hall of Fame|
Wunibald Kamm was an automobile designer, engineer, and aerodynamicist. He is best known for his breakthrough in reducing car turbulence at high speeds; the style of car bodywork based on his research has come to be known as a Kammback or a Kamm-tail.
One goal of automotive aerodynamics is to reduce the air turbulence, or drag, caused by the shape of the automobile. Aerodynamic drag may be reduced either by reduction of frontal area or by reduction of drag coefficient. In bodies such as automobiles and airships, drag decreases after the rear of a car's cross-sectional area is reduced to fifty percent of the car's maximum cross section; "the best position is nearer 45 per cent of the length, and ... to have this maximum cross- section nearer the rear end than the front, and its drag has proved even less". There are other aspects of the car's design such as keeping the flow of air attached to the body far to the back of the car as possible to minimize pressure drag (the Bernoulli relationship). A design with less drag means higher efficiency and an increased maximum velocity, given the same powertrain.
German Professor, Wunibald Kamm worked with aerodynamics engineer Baron Reinhard von Koenig-Fachsenfeld. They developed a design with a smooth roofline and a taper in the automobile's body that is suddenly chopped off at the rear end. This design makes the air flow act as if a full tapered "tail" was present on the vehicle. A full size prototype was developed in 1938. It was a four-door sedan featuring a sharply truncated rear end. The test car represented a compromise between a low air resistance and practicality in the automobile's size and shape.
In the 1920s, Kamm worked for Daimler designing engineering race car engines. Thereafter, a prototype, namely the Kamm “SHW Wagen” incorporated principles that have become standard parts of the car engineering toolbox. He paid particular attention to the suspension and minimizing vehicle weight. These improvements included extreme low weight design, an aluminum semi-monocoque body, front wheel drive, boxer-style engines (horizontally opposed cylinders), independent suspension on all wheels, and coil springs mated to hydraulic shock absorbers. His comprehensive approach to automotive engineering and design presaged the concept of "Mechatronics," a word that did not come into existence until 1971.
Established in 1930, the Research Institute of Automotive Engineering and Vehicle Engines located near Stuttgart (German: Forschungsinstitut für Kraftfahrwesen und Fahrzeugmotoren Stuttgart - FKFS) was called the "Kamm-Institut" after its founder and long-time director.
Kamm was inducted into the Automotive Hall of Fame. He did pioneering work in aerodynamics, driving dynamics, tire technology, minimalist construction techniques, engine combustion efficiency. Wind tunnels were an effectively applied technology, and he "built the first full-scale wind tunnel for motor vehicles." "Dr. Kamm, even today, and perhaps even more so because of his foresight, is considered one of the greatest researchers in automotive engineering." His work on turbulence is considered to have been "breakthrough" and fundamental.
He came to the U.S. as one of the first hundred German scientists stationed at the Dayton, Ohio Wright-Patterson Air Force Base and remained there as a consulting engineer until 1953. That year, he went as a professor to the Stevens Institute of Technology in Hoboken, New Jersey. For three years beginning in 1955 he was head of Mechanical Engineering at the Battelle Memorial Institute in Frankfurt, Germany.
The first "Kamm coupe"
In late summer of 1938, BMW tested a prototype of the so-called "Kamm-Coupe" based on their 328 chassis. It had a drag coefficient of only 0.25 compared to the great 1940 Mille Miglia winning BMW 328 Touring Coupe with drag coefficient 0.35. This automaker's naming of its coupé model appears to be the earliest use of "Kamm" to publicly describe an automobile body incorporating the Koenig-Fachsenfeld's design patent.
Kammback named production cars (USA)
- AMC Gremlin and AMC Eagle Kammback — The truncated hatchback design increased interior space capacity, not for streamlining.
- Chevrolet Vega Kammback — The station wagon design has more taper than the Gremlin, but not enough to gain aero-effects.
The Kammback "cut off tail" design continues to be popular. It often insinuates streamlining when used in production cars and is a design technique to make the vehicle look "sporty". Kamm's design approach is found on popular mass-market vehicles, supercars, alternative fuel vehicles, as well as for race cars.
- Institution of Mechanical Engineers (1970). Journal of Automotive Engineering, Volume 1. Institution of Mechanical Engineers - (Great Britain). Automobile Division. p. 18.
- SAE transactions. 27. Society of Automotive Engineers. 1932. p. 118.
- Barnard, R. H. (2001). Road vehicle aerodynamic design: an introduction. St Albans: MechAero. p. 43. ISBN 978-0-9540734-0-4.
- "Wunibald I.E. Kamm". Automotive Hall of Fame. Retrieved 25 March 2016.
- Hirschel, Ernst-Heinrich; Prem, Horst; Madelung, Gero (2003). Aeronautical research in Germany: from Lilienthal until today. 147. Springer-Verlag. p. 221. ISBN 978-3-540-40645-7. Retrieved 25 March 2016.
- "History (1930-1945)". Forschungsinstitut für Kraftfahrwesen und Fahrzeugmotoren Stuttgart. Archived from the original on 19 July 2011. Retrieved 25 March 2016.
- Ihrig, Ron (December 3, 2004). "Part 3: Production, Physics, Politics – Only the Strong Survive". Car Design News. German Design History. Archived from the original on 11 January 2011. Retrieved 25 March 2016.
- "1980 Automobiles". U.S. News & World Report. 89: 58. 1980. Retrieved 25 March 2016.
the SX/4 and Kammback are descended from the Spirit/Gremlin
- Witzenburg, Gary; Miller, Moss (September 1980). "Driving the new AMC Eagles". Popular Mechanics. 154 (3): 80–81. Retrieved 25 March 2016.
The Eagle Kammback looks very much like the old Gremlin.
- "1982 AMC Eagle brochure (Standard Features)". oldcarbrochures.org. Retrieved 25 March 2016.
- Dunne, Jim (September 1970). "Chevy's top ball talk about Vega: Starlet with a future". Popular Science. 197 (3): 58. Retrieved 25 March 2016.
Vega wagon is called Kammback, after W. Kamm
- "You call that a station wagon? (Chevrolet Vega ad)". Life. 71 (26): 45. 31 December 1971. Retrieved 27 March 2016.
... our Kammback ... Loving its sportyaerodynamic styling.
- Hafner, Chris (16 April 2008). "Car Lust--AMC Gremlin X". Retrieved 27 March 2016.
the Kamm-back quasi-hatchback rear end was actually considered a very sporty look in the 1970s
- Mueller, Mike (2006). Chrysler Muscle Cars: The Ultimate Guide. Krause Publications. p. 70. ISBN 9780873499705. Retrieved 27 March 2016.
(1967 Plymouth Barracuda) It was also downright sportylooking with its quasi-Kamm-back tail and racing-style gas cap.
- Gromer, Cliff (September 1988). "Happy Birthday Corvette!". Popular Mechanics. 165 (9): 60. Retrieved 27 March 2016.
(1968 Corvette): Longer, narrower and with a Kammbacktail section and removable rear window, the new body ...
- Harless, Robert (2003). Horsepower War: Our Way of Life. iUniverse. p. 67. ISBN 9780595302963. Retrieved 27 March 2016.
The Mach I option became the centerpiece around which, the “kammback” '71 Mustang was designed.
- Clarke, R.M. (1990). Shelby Cobra Gold Portfolio 1962~1969. Brooklands Books. p. 154. ISBN 9781855200234. Retrieved 27 March 2016.
The windshield was raked back and a long, sloping fastback ended in a sliced-off Kamm-back tail.
- Robinson, Peter (2002). "The Pininfarina 1800". Landcrab Owners' Club International. Retrieved 25 March 2016. - an explicitly Kamm-influenced design which informed the Citroën CX and Rover SD1
- Ziemnowicz, Christopher (2004). "The Origin of the Kammback Design". Archived from the original on 15 April 2012. Retrieved 25 March 2016. archived from the original at Wayback Machine Internet Archive
- "Dawn of the Automotive Design before 1930: People who influenced the BMW's car design". BMWism. 31 January 2013. Retrieved 25 March 2016. - People who influenced the BMW's car design