Man's early struggle with air
It is difficult to trace the aerodynamic history of the automobile without first looking back at its ancient origins in a time long before cars, trains, and airplanes. It appears as though people have been experimenting with aerodynamics for thousands of years-though the term is less than 100 years old-as the yearning to harness the wind and to utilize the surrounding atmosphere for the purposes of mobility is well engrained in the history of man. Appearing in Norse legends, a Finnish blacksmith named Ilmienen is said to have produced metal wings with which to fly. Shun, the emperor of China in 2000 B.C., was taught to fly by two princesses of his court, and 500 years later, Chinese writing depicts a flying cart with wheels that resemble propellers. Early tales in India tell the story of a flying wooden horse with a mechanized engine that could carry a rider. A winged human figure is illustrated on the grave of Ramses II of Egypt, and the folklore of Uganda in Africa includes flying men. Let's not leave out the myths of the flying carpet in the Far East and the brooms of witches throughout history and fiction.
In 67 A.D., as described in Octave Chanute's 1880 book La Navigation Aerienne, Simon the Magician made one of the earliest recorded attempts at flight in Rome, essentially using the air as a means of support with some form of primitive glider or kite (of course, it was referred to as a fiery chariot). Chanute wrote: "The people assembled to view so extraordinary a phenomenon, and Simon rose into the air through the assistance of the demons in the presence of an enormous crowd. But that St. Peter, having offered up a prayer, the action of the demons ceased..." Basically, he fell back to the earth, no doubt.
Hundreds of years later, DaVinci designed parachutes and helicopters after observing the flight of birds, but most notably sketched what he called an ornithopter, whose pilot flapped the wings via pulleys, employing both hands and feet, an advance beyond strapping wings to arms only. Research papers at the time suggested that perhaps birds and insects used some "vital force" that enabled them to fly and that could not be duplicated by an inanimate object.
Kites were the forerunners of airplanes that used lift and drag to obtain flight. They made their first appearance in China and other countries in the Far East, but they are believed to have been invented in China around 400 B.C. by Mo To Tzu. As history progressed, the speed at which we were able to understand flight and eventually the concepts of aerodynamics as they apply to airplanes, balloons, and cars would increase. A French locksmith named Besneir created a simple glider in 1678. Francois Blanchard expanded DaVinci's ornithopter by adding a balloon in 1781, and American Dr. John Jeffries, four years later, was the first to cross the English Channel in such a device, later proclaimed the greatest feat of the century. The Wright Brothers came along, and although they didn't invent the airplane, they ushered in the age of modern flight, aeronautical engineering, and paved the way for cars to cut through the very same atmospheric barrier that airplanes needed for flight.
At the same time the airplane was taking off as a serious form of machinery, on the ground the automobile was gaining immense popularity. Ford provided affordability but little else in the way of advancement toward the art of aerodynamics on production cars. This isn't to say that car designers weren't interested in the benefits of aerodynamics, since there are countless examples of racecars with streamlining, such as the 1916 Indy 500 winner, a Peugeot with a significant boat-tail tapering aft of the rear wheels. As early as 1907, a streamlined racing car called the Rocket reached 132 mph before it became airborne. It had a low drag coefficient, but it was still a bad aerodynamic design.
To a racecar designer, having the car slip easily through the air was of a vital importance, and at the time, less drag equals more speed (at least until you had to turn a corner), and there are many examples of this throughout early auto racing history.
However, early production car designs focused their attention not on how well the shape slipped through the air, but how well the engine and transmission could punch a hole through the same air.
It wasn't until 1921 when Edmund Rumpler produced the first truly aerodynamic car for the masses called the Rumpler-Tropfenauto, which loosely translates into "tear-drop car." Rumpler had plied his trade early on at the Benz factory and then went on to create Germany's leading aircraft company. After the Treaty of Versailles banished Germany from the skies, he returned to the car industry, and the Tropfenauto was the result. It was tear-drop-shaped when viewed from above, as the tear-drop is decidedly the most aerodynamic shape in nature, but it resembled a boat mounted on wheels from the side. Needless to say, the car caused a sensation (as most ahead-of-their-time cars do), but an attempt to commercialize it by Benz failed, thanks to its odd shape and futuristic design. The aerodynamics of his cars were better than that of most cars built around 70 years later, as it was reported that bored engineers at Lockheed's wind tunnel in Georgia strapped one of the few surviving examples to the wind tunnel. To their surprise, it produced a coefficient of drag (Cd) value of 0.27. Compared to modern cars with the benefit of computer-aided designs, this is a significant increase (Cd averages around 0.32 today). Around 100 examples of the Tropfenauto were built, and several of these unique vehicles can be seen set ablaze in the final scenes of Fritz Lang's movie Metropolis.