| Mercedes-Benz T80 | |
| Related: | Mercedes Silver Arrows Mercedes-Benz W125 Rekordwagen |
| Manufacturer: | Mercedes-Benz |
| Production: | 1939 (one-off) |
| Designer: | Ferdinand Porsche |
| Body Style: | six-wheel, mid-engined, 1-seater experimental racing car |
| Engine: | 44.5 litre (2,716 cu in) Daimler-Benz DB 603 V12 |
| Powerout: | 3,000 hp (2,200 kW; 3,000 PS) |
The Mercedes-Benz T80 is a six-wheeled vehicle built by Mercedes-Benz, developed and designed by Ferdinand Porsche in the late 1930s. It was intended to break the world land speed record, but never made the attempt, due to the project having been overtaken by the outbreak of World War II.
World-renowned German auto racer Hans Stuck's pet project was to take the world land speed record and he convinced Mercedes-Benz to build a special racing car for the attempt. Officially supported by Adolf Hitler (a race car fan influenced by Stuck), the project was started in 1937. Automotive designer Dr Ferdinand Porsche first targeted a speed of 5500NaN0, but after George Eyston's and John Cobb's successful LSR runs of 1938 and 1939 the target speed was raised to 6000NaN0. By late 1939, when the project was finished, the target speed was a much higher 7500NaN0. This would also be the first attempt at the absolute land speed record on German soil, Hitler envisioned the T80 as another propaganda triumph of German technological superiority to be witnessed by all the world, courtesy of German television. The same Autobahn course had already been proven ideal for record-breaking in smaller capacity classes, Britain's Goldie Gardner having exceeded 2000NaN0 there in a 1,500 cc MG.
The massive 44.5 litre Daimler-Benz DB 603 inverted V12 was selected to power the record-setting car. The engine was an increased displacement derivative of the famous DB-601 aircraft engine that powered the Messerschmitt Bf 109 fighter in production at the time, with the DB 603 ending up as the largest displacement inverted V12 aviation engine in production for Germany during the World War II years. The DB-603 fitted was just the third prototype (V3) engine of this variant and tuned up to 30000NaN0, roughly twice the power of the Bf 109 or the Supermarine Spitfire. The engine ran on a special mixture of methyl alcohol (63%), benzene (16%), ethanol (12%), acetone (4.4%), nitrobenzene (2.2%), avgas (2%), and ether (0.4%) with MW (methanol-water) injection for charge cooling and as an anti-detonant.
The difficulty of the challenge was met with money and engineering genius. By 1939, the T80 was fully completed at a cost of RM 600,000. The car was over 8m (26feet) long, had three axles with two of them driven, weighed over 2.7 metric tons (three short tons), and produced 30000NaN0 together with the aerodynamics of specialist Josef Mickl to attain a projected speed of 7500NaN0. Aerodynamically, the T80 incorporated a Porsche-designed enclosed cockpit, low sloping bonnet, rounded wings, and elongated tail booms. Midway down the body were two small wings to provide downforce and ensure stability - these wings were inspired by the wings of Fritz von Opel's Opel-RAK from 1928. The heavily streamlined twin-tailed body (forming the fairings for each pair of tandem rear wheels) achieved a drag coefficient of 0.18, an astonishingly low figure for any vehicle.
As ambitiously planned, Hans Stuck would have driven the T80 over a special stretch of the [1] Reichsautobahn Berlin — Halle/Leipzig, which passed south of Dessau (now part of the modern A9 Autobahn) between the modern A9 freeway's exits 11 and 12, which was 250NaN0 wide and almost 10km (10miles) long with the median paved over as the Dessauer Rennstrecke (Dessau racetrack). The date was set for the January 1940 "RekordWoche" (Record Week), but the war begun on September 1, 1939 prevented the T80 run. In 1939, the vehicle had been unofficially nicknamed Schwarzer Vogel (Black Bird) by Adolf Hitler and was to be painted in German nationalistic colours, complete with German eagle and Nazi swastika, but the event was cancelled and the T80 garaged.
The DB 603 aircraft engine was subsequently removed during the war while the vehicle was moved to safety and storage in Kärnten, Austria. The T80 survived the war and was eventually moved into the Mercedes-Benz Museum in Stuttgart for permanent display.
The T80 is currently on display at the Mercedes-Benz Museum in Stuttgart-Bad Cannstatt.