Igor Sikorsky

Sikorsky's fifth airplane, the S-5, won him a pilot's license and national attention in Russia; by 1912 his S-6-A took the highest award at the Moscow Aviation Exhibition. In 1913 he flew the Russky Vityaz, the first four-engine aircraft to leave the ground, then stretched the design into the Ilya Muromets family - airliners he converted into the world's first four-engine bombers when World War I arrived. The Russian Revolution sent him to the United States in 1919. Four years later he founded Sikorsky Aircraft and spent the 1930s building Pan American's ocean-crossing flying boats, including the S-42 Flying Clipper. In 1939 he flew the Vought-Sikorsky VS-300, the first viable American helicopter, pioneering the single main rotor and tail rotor layout most helicopters still use. He refined it into the R-4, the first mass-produced helicopter, in 1942.