NASA Ames' experience with V/STOL configurations in the late 1950s came from flying the VZ-3, X-14, and XV-3, along with the VZ-2 and VZ-4, and formed the basis for early attempts to define flying qualities criteria and to gain an understanding of operational techniques for these aircraft.
Turning propeller thrust through large angles proved a tempting idea to achieve VTOL flight, or at least STOL or super-STOL flight. Both Ryan and Fairchild built prototypes. The Ryan VZ-3RY Vertiplane of 1959 was a high wing aircraft using a single T53 turboshaft engine driving two 9 ft diameter propellers in underslung nacelles blowing large-chord flaps to redirect propeller and wing flow vertically. Residual jet thrust provided attitude control. The VZ-3RY used deflected propeller slipstream to augment wing lift, and a form of engine exhaust gas reaction control for low-speed pitch and yaw control. Ames added full-span slats to the wing to increase its lift.
Tests were carried out in the 40- by 80-foot wind tunnel to define its performance, stability and control, and handling characteristics. With any wind, the aircraft could nearly hover out of ground effect, but it was ungainly and difficult to control in the presence of gusts. Howard Turner led the project and Glen Stinnett and Fred Drinkwater did most of the flying. The aircraft was lost when Stinnett ran out of nose-down control at low power and the aircraft pitched inverted and crashed into San Francisco Bay. He was able to eject and survived to continue his career in Ames flight test. During flight tests at NASA/Ames Research Center, the aircraft suffered from a thrust deficiency in ground effect but could hover out of ground effect. The aircraft was subsequently rebuilt to complete the test program.
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