Sikorsky R-4, at the RAF Museum, Hendon, 03/73. Scanned print taken with a Kowa SET.
<a rel="nofollow" class="external text" href="https://www.flickr.com/people/58433307@N08">Hugh Llewelyn</a> from Keynsham, UK
CC BY-SA 2.0
<a rel="nofollow" class="external text" href="https://www.flickr.com/photos/camperdown/33439358454/">Sikorsky R-4</a>