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Multi-motored Airplanes, 1933

Vertical Craft

After aircraft production stopped, United Aircraft retained the Sikorsky Aviation design team and Sikorsky was able to return to his original goal: vertical take-off and landing craft.

On September 14, 1939, Igor Sikorsky piloted the VS-300 helicopter a few inches off the ground. The VS-300 followed a design patented by Sikorsky on March 19, 1935, and established the basic configuration of helicopter rotors which has changed little up to the current times. After demonstrating lifting, hovering, and rotating by a modified VS-300 in May, 1940, Sikorsky received Connecticut Helicopter License No. 1 and contracts from the U.S. Army in 1941 to develop military prototypes. During World War II, more than four hundred helicopters were delivered to the Army.