Sikorsky YR-4B/HNS-1 helicopter is seen in the 30 x 60 Full Scale Wind Tunnel.

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One of Langley's Sikorsky YR-4B/HNS-1 helicopters is seen in the 30 x 60 Full Scale Tunnel. The technician is setting up camera equipment for stopped-action rotor-blade photos. Sikorsky built hundreds of R-4 helicopters during World War II. It was the first mass-produced helicopter.

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Size: 3000px × 2175px
Photo credit: © NASA Archive / Alamy / Afripics
License: Licensed
Model Released: No

Keywords: aircraft, american, aviation, experimental, flight, full, helicopter, helicopters, historic, historical, history, naca, people, person, research, scale, sikorsky, technician, test, testing, tunnel, wind