Correct Answer: Igor Sikorsky

Solution : The correct answer is Igor Sikorsky.

The VS-300, the world's initial workable helicopter, took flight on September 14, 1939, in Stratford, Connecticut. The helicopter, designed by Igor Sikorsky and manufactured by the Vought-Sikorsky Aircraft Division of the United Aircraft Corporation, was the first to use a single main rotor and tail rotor configuration.