![](http://www.alamy.com/thumbs/6/A830850E-CA93-4E93-8A0C-500029743235/2C3AD30.jpg)
Sikorsky R-4B Hoverfly Helicopter, on display / an exhibit at the RAF Royal air force Museum in Hendon, London UK. (117)
The Sikorsky R-4 is a two-seat helicopter designed by Igor Sikorsky with a single, three-bladed main rotor and powered by a radial engine. The R-4 was the world's first large-scale mass-produced helicopter and the first helicopter used by the United States Army Air Forces,[1] the United States Navy, the United States Coast Guard and the United Kingdom's Royal Air Force and Royal Navy. In Navy and Coast Guard service, the helicopter was known as the Sikorsky HNS-1. In British service it was known as the Hoverfly.
Size: 5472px × 3648px
Location: RAF Museum London, Grahame Park Way, London, NW9 5LL. UK.
Photo credit: © David Gee / Alamy / Afripics
License: Licensed
Model Released: No
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