Igor Sikorsky United States in 1919, Sikorsky founded the Sikorsky Aircraft Corporation in 1923, and developed the first of Pan American Airways' ocean-conquering flying boats in the 1930s. In 1939, Sikorsky designed and flew the Vought-Sikorsky VS-300, the first viable American helicopter, which pioneered the rotor configuration used by most helicopters today. Sikorsky modified the design into the Sikorsky R-4, which became the world's first mass-produced helicopter in 1942. Igor Sikorsky was born in Kiev, Russian Empire (in present-day Ukraine), the youngest of five children. His father, Ivan Alexeevich Sikorsky, was a professor of psychology of Kiev St. Vladimir University, a psychiatrist
Igor Sikorsky a naturalized citizen of the United States. The Sikorsky Manufacturing Company moved to Stratford, Connecticut in 1929. It became a part of the United Aircraft and Transport Corporation (now United Technologies Corporation) in July of that year. The company manufactured flying boats, such as the S-42 "Clipper", used by Pan Am for transatlantic flights. Meanwhile, Sikorsky also continued his earlier work on vertical flight while living in Nichols, Connecticut. On February 14, 1929, he filed an application to patent a "direct lift" amphibian aircraft which used compressed air to power a direct lift "propeller" and two smaller propellers for thrust.