On September 29, 1907 at Douai (France), Louis Brequet nearly became the first man to pilot a helicopter in free flight. But as the machine rose lurching from the ground, several attendants rushed forward to hold it steady. Six weeks later, at Lisieux, another experimenter, called Paul Cornu, initiated a new chapter in aviation history when he gained vertical life unaided and hovered a few feet in the air. Years passed before any substantial progress was made beyond these tentative efforts. The next important step was taken by an Argentinian nobleman, the Marquis de P. Pescara, who build a biplane blade helicopter which was capable of forward as well as vertical flight. Though it achieved a straight run of 736 meters during trials in Spain in 1923, the machine was unstable and hard to maneuver.
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The real breakthrough was made by German Professor Heninrich Focke’s twin roter F-A61 – the first fully-controllable helicopter. After initial free flight trials on June 26, 1936, it went on to establish an altitude record of 11,242 ft, and endurance record of 80 minutes, a distance record of 143 miles and a speed record of 76 miles per hour. In 1938, a huge crowd of spectators watched the famous woman pilot Hanna Reitsch putting this revolutionary machine through its paces at the Deutschland Halle, Berlin- probably the first time an aircraft was actually flown inside a building. The first helicopter to go into production was Igor Sikoraski’s American-built single rotor R.4, used by both the United States Army and the Royal Navy during the World War II for liaison duties, naval and evacuation of wounded.