tandem two-seat VS-336 was designed to improve the R-4
Hoverfly's performance and first flew in 1943. Accepted into
U.S. Army Air Force service as the R-5 Dragonfly and as the HO2S
in the U.S. Navy.
The "D" model changed the landing gear
to a nosewheel configuration. A civil four-seat version--the S-51--first
flew in 1946 and was purchased by the U.S. Air Force as the H-5
and U.S. Navy as the HO3S.
This helicopter saw extensive action in Korea rescuing
United Nations pilots shot down behind enemy lines.