George de Bothezat and his contribution into the world aviation and astronautics

The article dedicated the life and scientific way of George de Bothezat, the first Doctor of Sciences in the field of aviation. Together with Nikolay Zhukovsky, Igor Sikorsky, Stephen Timoshenko, Alexander Fan-der-Flit, and Alexey Lebedev, he was one of the organizers of the Air Fleet of the Russian Empire. He is the author of various inventions: gyroscopic sight and other types of aviation equipment. We analyze works by G. Bothezat on the impulse theory of propellers. In particular, the scientist derived formulas for ensuring the flight stability of airplanes and helicopters. He developed training ballistic tables, which allowed making corrections for the speed of the flight and the direction of the wind. We briefly describe a biography of G. Bothezat, focusing on the student period of his life in Kharkiv, Ukraine, and the reasons for G. Bothezat’s departure to the United States in 1918. It is stated that it was there that his talent as a designer and creator of helicopters of the original system was disclosed in the best way. In 1922, George Bothezat obtained the financial support of the American government to build a workable helicopter model without prototypes and experiments, only based on the results of calculations. The reasons why G.Bothezat did not manage to achieve the launch of the serial production of helicopters are analyzed. We also mention the activities of the company founded by G.Bothezat, which was engaged in the production of fans of a new type for the US Navy. The Bothezat system fans were installed at the Rockefeller Center in New York as well as in American tanks. It is emphasized that I. Sikorsky also used the works by G.Bothezat in his research. It is stated that the flight trajectory calculated by G.Bothezat in air and airless space was used in the development of the American program of a manned landing on the Moon using the “Apollo” system.