In 1924, German scientist Anton Flettner used the principles of magnus effect to build a rotor ship. The magnus effect is a force which acts on a spinning body in an airstream to propel it forward perpendicularly. Flettner chanced upon the idea while holidaying at a beach with his wife. He observed the sand flowing over his rotating hand to understand the magnus effect. It was then that he realized the potential of that in sail propulsion. Flettner used rotorsails which were powered by engines to take advantage of this effect. The design of the flettner rotor vessel was thus based on this theory. The rotor ship was constructed by Anton Flettner, a German aviation engineer and inventor. In this he was helped by three other scientists, Albert Betz, Jacob Ackeret and Ludwig Prandtl. They used the theory of magnus effect which essentially is a phenomenon where an object spinning on its axis in a fluid creates a whirlpool around itself and as a result experiences a force perpendicular to the line of motion.
In October 1924, the flettner rotor vessel was constructed by Germaniawerft. The ship was a renovated schooner and it was named Buckau. It was fitted with two large rotors or cylinders 15 metres (50 ft) high and 3 metres (10 ft) in diameter. The rotor ship was driven by an electric propulsion system of 50 hp power. In February 1925, the Flettner rotor vessel made its maiden voyage from Danzig to Scotland across the North Sea. The journey did not cause the least cause for apprehension as the rotors behaved perfectly in even the roughest seas. The rotor ship, now renamed Baden Baden after the German town, sailed for New York passing through South America. The in-built systems in the rotor proved to be extremely efficient in all kinds of difficult situations. However, the vaoyage brought into light the fact that this system was less efficient than the conventional engines. The technology going behind the flettner rotor vessel is extremely sophisticated. The designs are being modified constantly during the process of engineering and manufacturing. This has been possible due to the modern testing methods which bring out the flaws in the design. This research has helped develop several different types of rotor ships. In recent times, German wind turbine manufacturer Enercon created a rotor ship and named it E-Ship 1. To diminish global warming, Stephen H Salter and John Latham has proposed the building of flettenr rotor vessels to spray seawater into the air to increase the reflectivity of clouds. A prototype of the flettner rotor vessel has been tested on Discovery Project Earth. The idea that drove Anton Flettner to build the first rotor ship is still being used for different purposes today.
