Adler streamlined sports car with panels made of PLEXIGLAS®

© Evonik Industries AG, Konzernarchiv Hanau

Streamlined race car: The award-winning Silver Arrows

16 cylinder, 520 hp, 400 km/h – that is what car fans today dream of and what enabled streamlined race cars to set records in speed in the 1930s. And curved panels made of PLEXIGLAS® played a significant part in this.

In the 1930s, five decades after the invention of the automobile, engineers started contemplating how they could achieve even higher speeds. Many of the cars built at that time were too heavy; their air resistance was very high and they consumed a great deal of fuel. Many manufacturers therefore turned to streamlining in order to design and build particularly streamlined, and thus fast, race cars.

PLEXIGLAS® brochure with streamlined race cars

Reduce air resistance

Streamlines represent the direction of a flow of air and indicate sections where the air is obstructed and cannot flow freely. Streamlines that are close to one another create air resistance. Automobile engineers still look at reducing air resistance, thus reducing fuel consumption. But the primary objective for race cars in the 1930s was to achieve higher speeds.

© Evonik Industries AG, Konzernarchiv Hanau

A new material for front windshields

To keep air resistance to a minimum, the new, low and rounded race car models required curved and concave panels. PLEXIGLAS® was the perfect material for this. The brand acrylic glass from Röhm could be formed into virtually any shape and made previously unthought-of designs possible.

The curved and concave panels made of PLEXIGLAS® integrated seamlessly into the streamlined shape of a modern chassis. In addition, PLEXIGLAS® was only half as heavy as the previously used silicate glass, which made race cars even faster. PLEXIGLAS® is also more durable than glass, which is a very important factor in vehicle construction as it helps prevent injuries from cuts in case of an accident.

Incredible speeds

The streamlined design of the cars, in combination with the lightweight panels made of PLEXIGLAS® led to multiple speed records being set in the 1930s. For example, Bernd Rosemeyer was the world’s first race car driver to break the 400 km/h speed record on a normal road in 1937. He drove his race car along the one-kilometer-long section on the highway between Frankfurt and Darmstadt with his 520 hp, Type C race car by Auto Union and achieved a top speed of 406.32 km/h. Rudolf Caracciola was the only other driver to top Rosemeyer’s speed. In a Mercedes-Benz W 125, Caracciola achieved a speed of 432.69 km/h just one year after Rosemeyer’s record. That is to this day – nearly 80 years later – the fastest speed ever recorded on a public road.

Race car driver Bernd Rosemeyer in his world-record-setting race car by Auto Union

National hero Bernd Rosemeyer

Bernd Rosemeyer (*1909, †1938) was one of the most popular and successful German race car drivers. In the 1930s, he was a Grand Prix driver for Auto Union and set multiple speed records and won numerous races. On January 28, 1938, Rosemeyer suffered a fatal accident when attempting to set a new world record.

© Evonik Industries AG, Konzernarchiv Hanau