The Bell 47 was the first helicopter certified for civilian use, on 8 March1946.[1][2] It was mostly designed by Arthur M. Young, who joined Bell Helicopter in 1941. More than 5,600 were produced until 1974, including 1,200 under license in Italy, 239 in Japan, and 239 in the UK.
The Bell 47 helicopter entered U.S. military service in late 1946, in a variety of versions and designations for three decades. In the Korean War (1950-1953) it was designated the H-13 Sioux by the United States Army, a highlight of its extensive career. It has also served as the helicopter of choice for basic helicopter flight instruction in many countries.
Early models were variable in appearance, with open cockpits or sheet metal cabins, covered or open structures, some with four-wheel landing gear. Model D and Korean War types settled to a more utilitarian style. The most common model, the 47G introduced in 1953, can be recognized by the full bubblecanopy, exposed welded-tube tail boom, saddle fuel tanks, and skid landing gear.
Later 47H and 47J Ranger models had a regular cabin with full cowling and monocoque tail boom. Engines were Franklin or Lycoming horizontally-opposed piston engines of 200 to 305 HP (150 to 230 kW). Seating varied from two to four. Many are still in use as trainers and in agriculture (as of 2005).
Initially, the US Navy procured several Bell 47s, designated HTL-1, between 1947 and 1958. The US Coast Guard evaluated this model, and procured two HTL-1s for multi-mission support in the New York Harbor. The most common US Navy version of the 47 was designated the HTL-4, and dispenses with the fabric covering on the tail boom. The US Coast Guard procured three HTL-5s in 1952 (similar to the HTL-4 but powered by a Franklin 0-335-5 engine) and used these until 1960.[4]
The Coast Guard procured two of Bell's Model 47G and designated them HUL-1G in 1959.[4]
The Los Angeles County Fire Department in California used the Bell 47 as the department's very first aircraft in 1957.
The British version of the 47G, called by the British Army the Sioux AH.1, was built by Westland Helicopters for use by the Army Air Corps, who used it until the early 1980s.citation needed The Sioux military version was often equipped with military evacuation panniers, one to each skid, with an acrylic glass shield to protect the patient from wind.
H-13 were produced in Japan by a Bell and Kawasaki venture; this led to the Bell-Kawasaki KH-4 variant, essentially a three seat version of the Model 47.
A three-seat, utility version of the U.S. Air Force's UH-13J. It was marketed as the Model 47J Ranger and powered by an Avco Lycoming VO-435 engine. A two-seat agricultural version was later known as the Ag-5. The 47G-5 was the last model to be produced by Bell.
Bell 47H-1
De-luxe version.
Military
YR-13/HTL-1
28 Bell 47A helicopters procured by the U.S. Air Force for evaluation. The YR-13 was powered by a 117 kW Franklin O-335-1 piston engine. 10 of the aircraft were evaluated by the U.S. Navy as trainers.
YR-13A
3 YR-13 aircraft winterized for cold-weather testing in Alaska.
HTL-2
US Navy equivalent of the commercial Model 47D. 12 built.
HTL-3
US Navy equivalent of the commercial Model 47E, powered by a 149-kW (200-hp) Franklin 6V4-200-C32 engine. Nine built.
H-13B
65 aircraft ordered in 1948 by the U.S. Army. All Army versions were later named Sioux.
H-13C
15 H-13B aircraft converted to carry external stretchers in 1952.
H-13D
Army two-seat version with skid landing gear, stretcher carriers, and Franklin O-335-5 engine.
OH-13E
H-13D configuration with three-seat aircraft with dual controls.
Modified Bell 47G powered by a Continental XT51-T-3 (Turbomeca Artouste) turboshaft. The first Bell helicopter powered by a turbine engine.
OH-13G
Introduced a small elevator on the tailboom.
UH-13J
Two Bell 47J Ranger aircraft utilizing the 179 kW Lycoming VO-435 engine acquired for VIP transport of the U.S. President by the U.S. Air Force. Originally designated as H-13J.
OH-13H/UH-13H
Equipped with a 186 kW Lycoming VO-435 engine. UH-13Hs were used by the U.S. Air Force.
OH-13K
Two converted H-13Hs with a larger diameter rotor and a 168 kW Franklin 6VS-335 engine for test evaluation.
TH-13L
Originally designated as the Navy HTL-4.
HTL-5
Utilized a Lycoming O-335-5 engine.
TH-13M
Incorporated a small movable elevator. Originally designated as the Navy HTL-6.
TH-13N
Two-seat, dual-control, instrument trainer with all-weather instrumentation. Originally designated as the Navy HTL-7.
UH-13P
Used aboard ice-breaking ships. Originally designated as the Navy HUL-1.
HH-13Q
Originally the HUL-1G, it was used by the U.S. Coast Guard for search and rescue.
UH-13R
Powered by an Allison YT63-A-3 turbposhaft engine. Original US Navy designation HUL-1M.
OH-13S
Three-seat observation helicopter to replace the OH-13H.
TH-13T
Two-seat instrument trainer for the U.S. Army based on the 47G-3B-1.
Sioux AH1
British military designation for both Agusta and Westland licence-built Model 47G-3B1s for the British Army.
Sioux HT2
British military designation for Westland licence-built Model 47G-3B1s for the Royal Air Force.
Japanese production version with redesigned, lengthened cabin, and redesigned control system
Bell 47 redesignations
The Bell 47 was designated under multiple systems, see United States of America military aircraft designation systems. It is best known as the H-13 Sioux, though it actually started as the YR-13 in 1946. It became the H-13 under the USAF, though the USN had called it the HTL.
In 1962 Army, Navy, and Air Force versions were redesignated under the new Tri-service system. Mainly, the H-13 based ones were converted to new standards which included a vehicle type designator and a mission symbol (2 letter prefix; OH, UH, XH, etc. This was a shift from the initial USAF 1948 system (with the numbered carried over from the USAAF/C system) and the USN 1922-1962 system to the new 1962 system.[9]
Castle Air Museum in Atwater, CA has a Bell H-13 with the M*A*S*H paint scheme in their "Hidden aircraft collection". Unfortunately, the H-13, along with other aircraft in their hidden collection, cannot be seen in the museum's main outdoor display because of weather conditions in the San Joaquin Valley.
Various other systems tested by the US including multiple tube 2.75" FFAR launchers, grenade launchers, modified infantry "Bazookas", small napalm canisters, and even a system capable of launching 4 Nord SS.10 anti-tank missiles.[12]
Popular culture
Bell 47G in M*A*S*H paint scheme.
The Bell 47 appeared, and played key roles, in film and television productions. It has been associated with both the M*A*S*H film, and the M*A*S*H television series, and the Whirlybirds TV series (1957–1959).[13]
Donald, David (1998). The complete encyclopedia of world aircraft. New York: Barnes & Noble Books. OCLC 52598955.
Jane, Fred T; Taylor, Michael John Haddrick (1989). Jane's encyclopedia of aviation. New York: Portland House. ISBN 0517691868.
Mutza, Wayne. H-13 Sioux Mini in Action. Carrollton, TX: Squadron/Signal Publications, 1995. ISBN 0-89747-329-0
Pelletier, Alain J (1992). Bell aircraft since 1935. Annapolis, Md: Naval Institute Press. ISBN 1557500568.
Riley, David (February 1958). "French Helicopter Operations in Algeria". Marine Corps Gazette. pp. 21-26.
Shrader, Charles R. (1999). The first helicopter war: logistics and mobility in Algeria, 1954-1962. Westport, CT: Praeger. ISBN 0275963888.
Spenser, Jay P. (1998). Whirlybirds a history of the U.S. helicopter pioneers. Seattle: University of Washington Press in association with Museum of Flight. ISBN 0295980583.
United States, Headquarters Department of the Army, Army Concept Team in Vietnam. Final Report of Essential Load of Scout Helicopters. Saigon, Vietnam: Army Concept Team in Vietnam, 1966.
USAAC/USAAF/USAF/Joint Service Helicopter designations 1941-
USAAC/USAAF/USAF 1941-Present; US Army 1948-1956, 1962-; US Navy 1962- Prefix R- used from 1941-1948, H- from 1948-1962, H- and a mission prefix 1962-present