Question

Which country introduced helicopter???

Answer 1

Stratford, Connecticut was the place

Answer 2

Hii friend here is ur answer

On September 14, 1939, the VS-300, the world's first practical helicopter, took flight at Stratford, Connecticut. Designed by Igor Sikorsky and built by the Vought-Sikorsky Aircraft Division of the United Aircraft Corporation, the helicopter was the first to incorporate a single main rotor and tail rotor design.

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