Bell H-13 Sioux
military helicopter series by Bell
The Bell H-13 Sioux is an American single-engine light helicopter built and produced by Bell Helicopter for the military and licence-produced by Westland Aircraft for the British military as the Sioux AH.1 and HT.2. It was the first helicopter to be certified for civil use. The H-13 Sioux is named after the eponymous Native American ethnic group.
Development
In 1947, the United States Army Air Forces (later the United States Air Force) ordered the improved Bell Model 47A. Most were designated YR-13 and three winterized versions were designated YR-13A. The United States Army first ordered Bell 47s in 1948 under the designation H-13. These would later receive the name Sioux.
Initially, the United States Navy procured several Bell 47s, designated HTL-1, between 1947 and 1958. The United States Coast Guard evaluated this model and procured two HTL-1s for multi-mission support in the New York Harbor. The most common U.S. Navy version of the 47 was designated the HTL-4, and dispensed with the fabric covering on the tail boom. The U.S. Coast Guard procured three HTL-5s in 1952 (similar to the HTL-4 but powered by a Franklin O-335-5 engine) and used these until 1960. The Coast Guard procured two of Bell's Model 47G and designated them HUL-1G in 1959.
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