NSU took a bold step forward with the large saloon Ro80 in 1967 with a one litre Wankel engine. Claus Luthe designed the superb aerodynamic body which would have been remarkable for any motor manufacturer, but particularly so for one that had only been making cars for about ten years and even those were economy microcars. Automatic transmission, four wheel discs set this car apart from other executive saloons. The most notable achievement of the car was that it was the first mass production car to be equipped with a Rotary engine. Designed by their own Felix Wankel, this engine has a curved triangular rotor which orbits a kind of fattened figure '8' chamber and will fire 3-times in each revolution. The NSU Ro80 had a twin-rotor Wankel engine of 995cc (although Wankel engines are often classified at twice their displacement), and gave 113bhp. Launched at the 1967 Frankfurt Show, the Ro80 was awarded European Car of the Year for 1968. However, the Wankel engine was unreliable with some customers having several replacement engines under the guarantee. The reputation of the car suffered and sales plummeted even though NSU did achieve an improved engine, better fuel and oil consumption. The development costs of the NSU Ro80, coupled with the teething troubles of this new technology was too much for NSU and in 1969 it agreed to a buyout by VW/Audi who promptly cancelled the car in 1977 after 35,000 were sold.