Igo Sikorsky
Igo Ivan Sikorsky was born in Kiev, Russia, in 1889. He began experimenting with building helicopters in 1909, but turned to fixed-wing aeroplanes. In 1911 he flew his S-5 aeroplane for more than an hour and achieved altitudes of 450 m/1,480 ft. He followed this by building the four-engined Le Grand and Ilia Mourometz. These were used as bombers by the Russian Army Air Service during the First World War.
After the Russian Revolution he emigrated to the United States. Sikorsky founded the Sikorsky Aero Engineering Corporation in 1923 (later merged to form the United Aircraft Corporation). He built several flying boats, including the S-40 American Clipper. In 1939 he built the successful helicopter, the VS-300. Igo Ivan Sikorsky died in 1972.