Sikorsky Aircraft and it became a part of [[United Aircraft and Transport Corporation]] (now [[United Technologies Corporation]]) in July of that year. [[File:Sikorsky Aircraft Corporation ad Model S-42 Clipper Flying Boat 1937.jpg|thumb|left|upright|Advertisement for [[Sikorsky S-42]] Clipper flying boat from 1937]] In the United States, Igor Sikorsky originally concentrated on the development of multi-engined landplanes and then amphibious aircraft. In the late 1930s, sales declined and United Aircraft merged his division with [[Vought Aircraft]]. He then began work on developing a practical helicopter. After first flying the [[VS-300]] he developed the [[Sikorsky R-4]], the first stable, single-rotor, fully controllable [[helicopter]] to enter full-scale
Igor Sikorsky with an international reputation, and an ardent Russian nationalist. Igor Sikorsky was an Orthodox Christian. When questioned regarding his roots, he would answer: "My family is of Russian origin. My grandfather and other ancestors from the time of Peter the Great were Russian Orthodox priests." Sikorsky's mother, Mariya Stefanovna Sikorskaya (née Temryuk-Cherkasova), was a physician who did not work professionally. She is sometimes called Zinaida Sikorsky. While homeschooling young Igor, she gave him a great love for art, especially in the life and work of Leonardo da Vinci, and the stories of Jules Verne. In 1900, at age 11, he