Less than two dozen years after the Wright Brothers attained powered, heavier-than-air, fixed-wing flight in the United States, Germany astounded the world in 1936 with demonstrations of the vertical flight capabilities of the side-by-side rotor Focke Fw 61, which eclipsed all previous attempts at controlled vertical flight. However, even its overall performance was modest, particularly with regards to forward speed. Even after Igor Sikorsky perfected the now-classic configuration of a large single main rotor and a smaller anti-torque tail rotor a few years later, speed was still limited in comparison to that of the helicopter's fixed-wing brethren.
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