Where did the modern coupe-crossovers and five-door coupes come from? After a second’s thought, the average man will say: the fashion on sloping roofs began with BMW X6 and Audi A5 Sportback. Those, who knows the history better, would object: and what about premium Citroenes of the fifties and Czech Tatras? But actually, the shape “drop with a cut off tail” was thought up even earlier. It was invented not for better sale, but to make the cars more streamlined. And it was not without a dusky German genius.
Rumpler Tropfenwagen, 1921
Car designers have known for a long time: the air resistance is a serious thing and it is necessary to reckon with it. One of the first people who understood this was the Austrian designer Edmund Rumpler. In 1921 he introduced the Rumpler Tropfenwagen, or “drop-shaped car”. The car, which looked like an airplane without wings, proved Edmund’s idea: “the drop shape is ideal from the point of view of aerodynamics”. The aerodynamic drag coefficient of the Tropenwagen was 0.28, which is comparable to the Porsche 911 generation 997, although there are more than eighty years between these cars.
BMW 328 Kamm Coupe, 1939
This was one of the first cars built according to the Kamm testament. The unusual design of the stern helped to reduce the Cx from 0.35 in a conventional coupe to 0.25. The top speed at the tests was 230 km/h, and this at the end of the thirties! It was impossible not to use such success in races, and in 1940, Kamm Coupe was sent to the Mille Miglia, but the car got off the track because of technical problems. And in 2010, BMW built a replica, which is shown in this photo.
Aston Martin DP215, 1963
And this Aston Martin is another car that was destined to be faster than the Ferrari 250 GTO. It is also the last sports car created by the brand’s racing division for the 24 Hours of Le Mans. The DP215’s debut was brilliant: that same year, on the Mulsanne straight, it accelerated to 319.6 kilometers per hour, though it then left the track due to a breakdown. Half a century later, in 2018, it was sold at a Sotheby’s auction for $21.5 million.
Citro¸n SM, 1970
With such “ancestors” as the Citroen Traction Avant and DS, the three-door SM had no right to be an ordinary car. And it was not – swivel headlights, hydropneumatic suspension, V6 engine designed by Maserati, one-spoke steering wheel… The hatchback could also boast a good streamlining for its time (Cx = 0.34). Unfortunately, good sales in North America were spoiled first by the fuel crisis, and then by the new safety regulations. And the merger with Peugeot in 1975 finally finished off the SM.
Honda CR-X, 1983
The CR-X turned out to be one of Honda’s first experiments with the Kamm tail. The hatchback was loved not only in its native market, but also in the United States, for which the Japanese made their own modification, stripped of the hyphen in the name. There were a lot of reasons for sympathy: agility and good handling combined with excellent fuel economy. And the unusual profile of the car was preserved in the second generation CR-X, and in the hybrid three-door CR-Z, which was produced from 2010 to 2016.
Honda Insight, 2008
The second-generation Insight is a prime example of a modern mass-market hybrid. The Toyota Prius (starting from the second generation) and Hyundai IONIQ are also included here… They are too similar in profile. Professor Kamm’s legacy did them good: for example, the factor of aerodynamic drag of Honda Insight was 0,28, that is better, than some supercars have. And where there’s streamlining, there’s eco-friendliness. For the Insight, the fuel consumption of 4.5 liters per 100 kilometers was declared, which is commendable for a one and a half ton machine of considerable size.
Mercedes-Benz Concept IAA, 2015
But if in the A7 and other “Arcana” the Camm’s tail is an element of image, in the Mercedes-Benz Concept IAA it is part of a whole bouquet of aerodynamic solutions. In “design mode” Cx of the concept is 0,25, but it is necessary to activate “aerodynamic mode”, and the four-door begins to transform not worse than a cab from a French comedy. Holes in the grille are closed, the splitter in the front bumper moves back, the concave wheel rims become flat, and eight flaps on the stern are extended, which increase the length of the car by 390 millimeters. The Cx in this mode reaches a figure of 0.19, the lowest in the world.