HH-43 Kaman Huskie at the Olympic Air Show 2012 in Olympia WA
The Huskie had an unusual inter-meshing contra-rotating twin-rotor arrangement with control effected by servo-flaps. It also had no tail rotor which made the helicopter very quiet in flight The first prototype flew in 1947 and was adopted by the U.S. Navy with a piston-engine. In 1954 in an experiment by Kaman and the US Navy one HTK-1 was modified and flew with its piston engine replaced by two turbine engines becoming the world's first twin turbine helicopter. Later the Air Force adopted a version with one turboshaft engine: HH-43B and F versions.
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