GENERAL KNOWLEDGE

Detailed explanation-1: -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.

Detailed explanation-2: -Back in Kiev in May 1909, he began construction of a helicopter.