TheBell H-13 Sioux is an American single-enginelight helicopter built and produced byBell Helicopter for the military and licence-produced byWestland Aircraft for the British military as theSioux AH.1 andHT.2. It was the first helicopter to be certified for civil use.[2]
Initially, theUnited States Navy procured several Bell 47s, designatedHTL-1, between 1947 and 1958. TheUnited 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 theHTL-4, and dispensed with the fabric covering on the tail boom. The U.S. Coast Guard procured threeHTL-5s in 1952 (similar to the HTL-4 but powered by a Franklin O-335-5 engine) and used these until 1960.[4] The Coast Guard procured two of Bell's Model 47G and designated themHUL-1G in 1959.[4]
The H-13 was one of the principal helicopters used by the U.S. Army during theKorean War, with the H-13D variant being the most prevalent. During the war it was used in a wide variety of roles including observation, reconnaissance, and medevac. From its role in medevac flights, it gained the nickname "Angel of Mercy". It was also used as an observation helicopter early in theVietnam War, before being replaced by theHughes OH-6 Cayuse in 1966.
The Bell 47 was ordered by the British Army as the Sioux to meet specification H.240, withlicensed production byWestland Helicopters. In order to comply with the terms of its licence agreement withSikorsky Aircraft, which prevented it building a U.S. competitor's aircraft, Westland licensed the Model 47 fromAgusta, who had purchased a license from Bell.[5] the first contract was for 200 helicopters. The first 50 helicopters of the contract were built byAgusta at Gallarate in Italy followed by 150 built by Westland at Yeovil. The first Westland Sioux made itsmaiden flight on 9 March 1965.[6]
The Sioux is a single-engine, single-rotor, three-seatobservation andbasic training helicopter. In 1953, the Bell 47G design was introduced. It can be recognized by the full"soap bubble" canopy (as its designerArthur M. Young termed it),[7] exposed welded-tube tail boom, saddlefuel tanks and skid landing gear. In its UH-13J version, based on the Bell 47J, it had a metal-clad tail boom and fuselage and an enclosed cockpit and cabin.
The H-13 and its military variants were often equipped withmedical evacuation panniers, one to each skid, with anacrylic glass shield to protect the patient from wind.
The development of the Sioux was helped greatly by Bell's implementation of a short weightedgyro-stabilizer bar beneath and perpendicular to the main rotor. It hadstreamlinedcounterweights at both tips and was linked so it determined which plane the rotor was in and kept it horizontal.[8] The stabilizer, which was connected to thecyclic pitch control, acted as a hingedflywheel using gyroscopic inertia to keep the rotor blades in plane and independent offuselage movement due to wind. It ensured that the system had enoughinertia due to flight as well, soautorotation would function in case of engine failure.[9]
A single 260 hpLycoming VO-435piston engine was fitted to the 47G variant. Fuel was fed from two high-mounted external tanks. A single two-bladed rotor with short inertial stabilizing minor blades was used on the Sioux.[6]
[a] 28 Bell 47A helicopters procured by the United States Army Air Forces for evaluation. The YR-13 was powered by a 175 hp (130 kW) Franklin O-335-1 piston engine. 10 of the aircraft were transferred to the U.S. Navy for evaluation as theHTL-1, with two HTL-1s later transferred to US Coast Guard.[11]
YR-13A
3 YR-13 aircraft winterized for cold-weather testing in Alaska. RedesignatedYH-13A in 1948.[12]
HTL-2
US Navy equivalent of the commercial Model 47D. 12 built.[13]
HTL-3
US Navy equivalent of the commercial Model 47E, powered by a 200 hp (149 kW) Franklin 6V4-200-C32 engine. Nine built.
H-13B
65 aircraft ordered in 1948 by the U.S. Army.[12] All Army versions were later named Sioux.
YH-13C
One H-13B used as engineering testbed. Fitted with skid undercarriage and open, uncovered tailboom.[12]
H-13C
16 H-13B aircraft converted to carry external stretchers in 1952, with skid landing gear and open tail boom of YH-13C.[12]
H-13D
Army two-seat version based on commercial model 47D-1, with skid landing gear, stretcher carriers, and Franklin O-335-5 engine. 87 built.[12]
OH-13E
H-13D configuration with three-seat aircraft with dual controls. 490 built.[12]
Modified Bell 47G powered by a Continental XT51-T-3 (Turbomeca Artouste) turboshaft.[12] The first Bell helicopter powered by a turbine engine.
OH-13G
Three-seater based on commercial model 47-G. Introduced a small elevator on the tailboom. 265 delivered to US Army.[14]
OH-13H/UH-13H
Based on 47G-2. Equipped with a 250 hp (186 kW) Lycoming VO-435 engine. At least 453 acquired by US Army.[14] UH-13Hs were used by the U.S. Air Force.
UH-13J
TwoBell 47J-1 Rangers acquired by the U.S. Air Force for VIP transport of the U.S. President. Originally designatedH-13J.
OH-13K
Two converted H-13Hs with a larger diameter rotor and a 225 hp (168 kW) Franklin 6VS-335 engine for test evaluation.
TH-13L
Originally designated as the NavyHTL-4.
HTL-5
Utilized a Franklin O-335-5 engine.
TH-13M
Incorporated a small movable elevator. Originally designated as the NavyHTL-6.
HH-13Q
Originally theHUL-1G, it was used by the U.S. Coast Guard for search and rescue.
UH-13R
Powered by an Allison YT63-A-3 turboshaft engine. Original US Navy designationHUL-1M.
OH-13S
Three-seat observation helicopter based on 47G-3B to replace the OH-13H. 265 received by US Army.[14]
TH-13T
Two-seat instrument trainer for the U.S. Army based on the 47G-3B-1, powered by 270 hp (201 kW) Lycoming TVO-435-D1B. 411 purchased.[14]
Sioux AH.1
General purpose helicopter for the British Army, 50 built by Agusta (Agusta-Bell 47G-3B1) and 250 built by Westland (Westland-Agusta-Bell 47G-3B1).[15] A small number also used by3 Commando Brigade Air Squadron of the Royal Marines.
Sioux HT.2
Training helicopter for theRoyal Air Force, 15 built by Westland.
Texas Helicopter Corporation single-seat conversion of OH-13E helicopters for agricultural use, powered by 200 hp (150 kW)Lycoming TVO-435-A1E engines. Certified 1976.[17]
Texas Helicopter M74A
Texas Helicopter Corporation single-seat conversion of OH-13H helicopters for agricultural use, powered byLycoming TVO-435 engine rated at 240 hp (180 kW) for 2 minutes. Certified 1977.[17]
Texas Helicopter M79S Wasp II
Texas Helicopter Corporation conversion for agricultural use, with tandem seating and stub wing fuel tanks. Powered byLycoming TVO-435 engine rated at 270 hp (200 kW) for 5 minutes.[17]
Texas Helicopter M79T Jet Wasp II
Texas Helicopter Corporation conversion of Bell 47G helicopters for agricultural use, powered by 420 hp (310 kW)Soloy-Allison 250-C20S engines.
H-13 Sioux (Bell 47-G3) registration NZ3705 Sioux on display at theRoyal New Zealand Air Force Museum atWigram. The aircraft is displayed in its RNZAF colour scheme when it was retired from service in 2012.NZ3705[56]
48-0796 – South Carolina Military Museum inColumbia, South Carolina. It is the first H-13B airframe, serial number 101, and came off the production line in mid-July 1948.[72][73]
The H-13 has appeared, and played key roles, in many film and television productions. It has been associated with both theM*A*S*H TV series (1972–1983) and thefilm of the same name (1970), prominently featuring the H-13 in its opening credits, and played a central role in theseries finale, which still holds the record as thehighest rated single episode broadcast in America.[106][107] The series helped popularize the H-13 as the helicopter most people now associate with theKorean War.[108] The H-13 also played a key role in theWhirlybirds TV series (1957–1959).[109][110]
^In the military of the United States, the Bell 47 carried several designations prior to 1962.R-13 was the first designation by theUnited States Army Air Forces, while the Navy designated their training version asHTL. In 1948, theUnited States Air Force changed the designation toH-13 which was also adopted by the Army, adding the nameSioux. The Navy and Coast Guard designated utility models asHUL. In 1962, under a joint designation system created by the Department of Defense, the designations for all of the helicopters were changed to a mission symbol followed by the vehicle type designator creating a two-letter prefix (OH, UH, XH, etc.), but the Bell 47 retained its original series number, 13 and the Army's popular name. To denote different models, a letter suffix was appended to the designation.[10]
^The OH-1 was capable of carrying twinM37C .30 caliber machine guns, or twinM60 machine guns.[105] They rarely did so however, because according to aMilitary Channel documentary on theAH-1 attack helicopter ("World's Deadliest Aircraft" series), the guns' recoil was too great a strain on the engines.
^Arthur M. Young.Arthur Young on the Helicopter (Part 2)(YouTube) (YouTube). Arthur M. Young. Event occurs at 10:15 to 11:45.Archived from the original on 2021-12-15. RetrievedApril 8, 2016.I thought the bubble was a great idea, and we tried it. It consisted of taking a large sheet of Plexiglas, and a plywood form, cut for the final dimension for the outside of the bubble, then heating the Plexiglas, putting it under the plywood form, letting air pressure come up through the middle, and it would blow just like asoap bubble. And, then we had a gauge saying how far to blow, and when it reached that point, we turned off the air pressure.
^"BELL 47G HTL-6".Canada Aviation and Space Museum. Canada Science and Technology Museums Corporation. Archived fromthe original on 2 March 2017. Retrieved2 March 2017.
^"FAA REGISTRY [N9025]".Federal Aviation Administration. U.S. Department of Transportation. Retrieved15 December 2020.
^"Aircraft".Cavanaugh Flight Museum. Retrieved2 March 2017.
^"FAA REGISTRY [N55ER]".Federal Aviation Administration. U.S. Department of Transportation. Archived fromthe original on 15 November 2019. Retrieved2 March 2017.
^abc"Rotary Wing".United States Army Aviation Museum. Army Aviation Museum Foundation, Inc. Archived fromthe original on 5 November 2016. Retrieved19 August 2016.
^"SIOUX".Pima Air & Space Museum. PimaAir.org. Archived fromthe original on 10 May 2019. Retrieved19 August 2016.
^ab"Sioux on Display".National Naval Aviation Museum. Naval Aviation Museum Foundation. December 16, 2013. Archived fromthe original on 5 September 2020. Retrieved19 August 2016.
^"SIOUX".Pima Air & Space Museum. PimaAir.org. Archived fromthe original on 12 October 2016. Retrieved19 August 2016.
^"FAA REGISTRY [N147DP]".Federal Aviation Administration. U.S. Department of Transportation. Archived fromthe original on 17 November 2019. Retrieved3 March 2017.
Boulay, Phillipe (November 1984). "Le vol de Gendarme".Le Fana de l'Aviation (in French). No. 180. pp. 4–7.
Cooper, Tom (2017).Hot Skies Over Yemen, Volume 1: Aerial Warfare Over the South Arabian Peninsula, 1962-1994. Solihull, UK: Helion & Company Publishing.ISBN978-1-912174-23-2.
Donald, David (1997).The Complete Encyclopedia of World Aircraft. NY, NY: Barnes & Noble.ISBN0-7607-0592-5.
Elliott, Bryn (May–June 1999). "On the Beat: The First 60 Years of Britain's Air Police, Part Two".Air Enthusiast (81):64–69.ISSN0143-5450.
Frawley, Gerard (2003).The International Directory of Civil Aircraft, 2003–2004. Fyshwick, ACT, Australia: Aerospace Publications Pty Ltd.ISBN1-875671-58-7.
Gunston, Bill (1986).American Warplanes. New York: Crown Publishers Inc.ISBN0-517-61351-4.
Hagedorn, Daniel P. (1993).Central American and Caribbean Air Forces. Tonbridge, Kent, UK: Air-Britain (Historians) Ltd.ISBN0-85130-210-6.
Harding, Stephen (1990).US Army Aircraft since 1947. Shrewsbury, UK: Airlife Publishing.ISBN1-85310-102-8.
Hatch, Paul F. (December 1984). "Air Forces of the World: Zambian Air Force".Air Pictorial. Vol. 46, no. 12. pp. 457–458.
James, Derek N. (1991).Westland Aircraft since 1915. London: Putnam.ISBN0-85177-847-X.
Mutza, Wayne (1995).H-13 Sioux Mini in Action. Carrollton, TX, USA: Squadron/Signal Publications.ISBN0-89747-345-0.
Pelletier, Alain J (1992).Bell Aircraft since 1935. Annapolis, Md: Naval Institute Press.ISBN1-55750-056-8.
Riley, David (February 1958). "French Helicopter Operations in Algeria".Marine Corps Gazette:21–26.
Shrader, Charles R. (1999).The first helicopter war: logistics and mobility in Algeria, 1954–1962. Westport, CT: Praeger.ISBN0-275-96388-8.
Taylor, John W. R., ed. (1980).Jane's All The World's Aircraft 1980-81. London: Jane's Publishing.ISBN0-7106-0705-9.
Taylor, Michael John Haddrick (1989).Jane's encyclopedia of aviation. New York: Portland House.ISBN0-517-69186-8.
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.
Vetter, Frank (2005). "Debrief: German Border Police 50th anniversary".International Air Power Review. Vol. 17. pp. 20–21.ISSN1473-9917.
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