The Economic Times

In 1939, a Russian-American aviator invented the first practical and mass-produced single-rotor helicopter revolutionizing modern aviation

In 1939, a Russian-American aviator invented the first practical and mass-produced single-rotor helicopter revolutionizing modern aviation. Igor Sikorsky developed the VS-300, which first flew on September 14, 1939. Its single main rotor and anti-torque tail rotor became the layout for modern helicopters. The later Sikorsky R-4 became the first mass-produced helicopter in 1942.