We treat you this time, dear reader, on a following story about famous men who changed motorsport and/or made such an important contribution to the development of the automobile, that the automotive world has never been the same again since then. Such a man was the Austrian nobleman Robert Eberan von Eberhorst. He made his mark as a formidable engineer not only before WW2, but also throughout the war and also in the fifties, and one of his post-war creations, the Aston Martin DB3 sports racing car, is still raced in historic sporting events, right until this day…

But there is so much more, just read on!

Hans Knol ten Bensel

Here you see Robert Eberan von Eberhorst in the middle, on May 30, 1937, on the Avusrennen, discussing the Auto Union racing strategy, with racing driver Bernd Rosemeyer on the left, and Prof. Porsche on the right… Look at the smart dress of  racing pilot Rosemeyer, the man who could then master the rear engined Auto Union better than enyone else…(Use Ctrl + to enlarge the drawing…)   

Eberan was born in the cradle of Austrian nobility, which was going through dramatic changes at the outcome of WW1 and the demise of the Austro-Hungarian empire. This also let to the total abolishment in 1918 of the Austrian nobility. From that year on, the family changed their name to a shortened Eberan-Eberhorst. Nobility then also had to earn its keep, and so did Robert. He went to study at the Vienna Technical University until 1927, and earned his engineering master’s degree.

The TU Dresden, which emerged relatively unscathed from the ravages of war, as it stands today, still with its typical tower… 

Later that year he moved to Dresden, and joined the Institute for Automotive Engineering at the Dresden Technical University. The TU Dresden, – Technische Universität Dresden – by the way, still exists, and is flourishing more than ever. This Technische Universität Dresden has its roots in the Royal Saxon Technical School that was founded in 1828. Today it is a university that unites the natural and engineering sciences with the humanities and social sciences, as well as medicine. This wide range of disciplines is unique in Germany. It has now not less than 33.506 students. We could write almost a book here about this institution, but here the focus is of course on Robert Eberan von Eberhorst.

At the TU Dresden, Robert worked as a research assistant and a Ph. D. candidate. But he was soon spotted for his extraordinary talents by Dr. Ferdinand Porsche, who persuaded him to join Auto Union in 1933.

Ma(r)king his way as a development engineer…

He started off in this function at the Auto Union Racing Department at the Horch Works in Zwickau. His task was to turn Porsche’s ideas into physical reality. What a fantastic time this must have been. Young Robert must have worked closely together with draughtsmen, engineers, specialist suppliers of engine parts, valve and piston specialists, bearing experts, chassis and metallurgic specialists and designers, you name it. What a brave new world this must have been.

Eberan von Eberhorst oversaw the design and development of the 3 liter V12 double compressor engine of the Type D…

For instance, just look at the pistons, to name one item amongst many. People like genius Ernst Mahle joined the company Elektrometall GMBH in 1922, and in 1938 this became Mahle KG (Kommandit Gesellschaft). But in In 1927, this company developed the first controlled-expansion piston in Germany and in 1931, the world’s first aluminum ring carrier piston for Diesel engines. Following this, piston technology was steadily improved. This superb piston technology was of course also found in the Auto Union racing engines. Did you know that in 2017, In 2017, the MAHLE Group generated sales in excess of €12.8 billion? The company is located in Stuttgart-Bad Cannstatt, yes, the birthplace of the first automobile in the world, the Benz Tricycle Motorwagen. It has now several business units, amongst others the Engine Systems and Components: This business unit supplies the global automotive industry with piston and valve train components and cylinder components.

A pioneer in aerodynamics…

But Robert Eberan von Eberhorst had also a keen eye for high speed behavior of record cars: he developed the side skirts and the aerodynamic bodywork along the belly of the Auto Union Type C Streamliner/Rekordwagen, and so set the first practical steps into the science of ground effect and aerodynamic downforce.

… and his masterpiece: the type D Auto Union racing car.

In 1938 Porsche left Auto Union for even more important engineering work (further development of the Volkswagen and other things…) and his first task was to fully redesign the Auto Union Type C Grand Prix car. Indeed, a new Grand Prix technical formula was into force, and engine volume was now reduced to 3 liters, which meant a significant redesign of the V16 engine, which ended its life in the type C with 6 litre displacement. Actually, the whole car was redesigned too, and the rear swing axle was replaced by a De Dion layout. But the massive torque of the now V12 485 HP twin Roots compressor engine (550 NM at 4000 rpm) still made the car oversteer under power.

In 1939, a modified version of the Type D was introduced. A characteristic feature of this layout was the Roots dual compressor, the installation of which required an additional air box to be incorporated in the bonnet. The Type D with dual compressor made its first race appearance on 23 June 1939 at the Belgian Grand Prix at Spa-Francorchamps.

For this V12, the two cylinder blocks remained, inclined now at an angle of 60 instead of 45 degrees, and now with the higher revs three camshafts were used instead of one single camshaft to operate all the valves.

Revs were still rather conservative for a racing engine though, with maximum power obtained at 7,000 rpm. Supercharger boost pressure was now raised from 0,95 to 1,67 bars. Fast these 850 kg heavy D types certainly were: not less than 340 km/h top speed was recorded…

For the French Grand Prix at Reims in July 1938, the racing department in Zwickau built two Streamliner racing cars on the basis of the 12-cylinder Type D, but both of these were withdrawn following accidents in training.

Robert Eberan-Eberhorst tested each new racing car thoroughly and he developed an on-board recording instrument to plot parameters such as car speed, engine speed, gear change and braking points.

He gained his doctorate in 1940 and from 1941 he was appointed to a full professorship at the Dresden Technical University. During World War II he was involved in the design of the Tiger tank, initial testing of the V1/V2 rockets, and provided much research data on improving fuel consumption. The latter was a topic he studied further right into the ‘60s, writing scientific articles and papers about the subject.

After WWII, he created a formidable Aston Martin DB3S…

Of course, Dresden was unsafe territory after the war, as it was Soviet occupied. Robert Eberan-Eberhorst fled to Gmünd and worked in 1947 with Ferdinand Porsche’s son Ferry at the design and creation of the Porsche 356.

He became involved in the Italian Cisitalia project initiated by Piero Dusio, together with formidable engineers like Dante Giacosa and Giovanni Savonuzzi from Fiat. He was hired together with Carlo Abarth when Cisitalia decided to enter Grand Prix racing. There is much more to tell about Savonuzzi, who designed some truly beautiful cars. But that is also the subject of a further report…

Robert Eberan von Eberhorst designed the chassis of the Jowett Jupiter…(Use ctrl + to enlarge). 

Robert had established a solid reputation as one of the most important theorists in car design, and in 1949 he went to England, and worked in Dunstable for ERA on the tubular steel chassis of the Jowett Jupiter. The suspension used soft torsion bars and anti-roll bars front and rear with independent suspension at the front. The 1,5 liter flat four engine was mounted very far forward ahead of the front axle line with the radiator low behind it over the gearbox.

The post-war masterpiece however was the Aston Martin DB3 sports racing car he designed in 1950. A stunning 2,6 liter six cylinder racing car indeed. When he was designing the DB3, Robert wrote a remarkable study for the Automobile Engineer, entitled “Roll Angles”. This theoretical study followed the paper written by an excellent ex-Rolls-Royce engineer Maurice Olley’s, focusing on “Road Manners of the Modern Car”. Eberhorst continued here the interesting research done by Olley, and his contribution was to show how the several constants used in Olley’s complex equations could be established experimentally.

In 1953 Eberhorst returned to Germany to his old love, Auto Union, which was reviving from the ashes, and building in Düsseldorf the post war two stroke three cylinder DKW’s 3=6.

The 1955 DKW Sonderklasse 3=6 with three cylinder two stroke engine proved quite popular… 

He was appointed General Manager for Technical Development. Three years later, he moved to the Battelle Institute in Frankfurt as Head of Mechanical Engineering and in 1960 he took over responsibility for the Combustion Engines and Automotive Engineering Institute at Vienna University. He retired from there in 1965 although continuing to author important technical papers. We wonder whether the Daimler very efficient “Mitteldruckmotor”, which was to be built in the DKW F102 and becoming the Audi 60, was also inspired by Eberan von Eberhorst’s ideas…

Hans Knol ten Bensel