London-based manufacturerPoduhvat has developed a wind turbine which they claim can produce five times more energy than traditional wind turbines with the same rotor size. The contra-rotating Whetar ...

Serious engineering work on contra-rotating open rotors for aircraft propulsion dates back to the late 1940s, particularly as a means to enhance fuel efficiency and extend the endurance of long-range ...

MESSRS. ROTOL AIRSCREWS, LTD., have now completed the development, to the production stage, of a constant speed contra–rotating airscrew, the principle of which was mentioned in NATURE of May 17, 1941 ...

During World War II, Daimler-Benz explored an unconventional fighter concept built around a massive experimental V16 engine. Instead of placing the propeller at the nose or tail, the design mounted ...