Sikorsky HNS-1 (YR-4B)

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Size: 1856px × 1345px
Photo credit: © NG Images / Alamy / Afripics
License: Licensed
Model Released: No

Keywords: astronomy, bygone, full, fullscaletunnel, helicopter, historic, history, hns-1, hns1, langley, naca, nasa, scale, sikorsky, space, tunnel, yr-4b, yr4b