Bell H-13 Sioux

H-13 Sioux
An OH-13 in flight
Role Light observation helicopter
National origin United States
Manufacturer Bell Aircraft / Bell Helicopter
First flight 8 December 1945 (Bell 47 prototype)[1]
Status Retired
Primary users United States Army
United States Air Force
United States Navy
British Army
Developed from Bell 47
Variants H-13J Sioux
Bell 207 Sioux Scout
XH-13F

The H-13 Sioux was a two-bladed, single engine, light helicopter built by Bell Helicopter. Westland Aircraft manufactured the Sioux under license for the British military as the Sioux AH.1 and HT.2.

Contents

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.[2]

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 dispenses 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.[3] The Coast Guard procured two of Bell's Model 47G and designated them HUL-1G in 1959.[3]

The H-13 was used as observation helicopter early in the Vietnam War, before being replaced by the OH-6 Cayuse.

The Bell 47 was ordered by the British Army as the Sioux to meet specification H.240, with licensed production by Westland Helicopters. In order to comply with the terms of its licence agreement with Sikorsky Aircraft, which prevented it building a U.S. competitors aircraft, Westland licenced the Model 47 from Agusta, who had purchased a license from Bell.[4] the first contract was for 200 helicopters. The first 50 helicopters of the contract were built by Agusta at Gallerate in Italy followed by 150 built by Westland at Yeovil. The first Westland Sioux made its maiden flight on 9 March 1965.[5]

Design

The Sioux is a three-seat observation and basic training helicopter. In 1953 the Bell 47G design was introduced. It can be recognized by the full bubble canopy, exposed welded-tube tail boom, saddle fuel tanks and skid landing gear.

The H-13 and its military variants were often equipped with medical evacuation panniers, one to each skid, with an acrylic glass shield to protect the patient from wind.

A single 260 hp Lycoming VO-435 piston engine was fitted to the 47G variant. Fuel was fed from two high-mounted external tanks. A single two-bladed rotor with short inertial stabilising minor blades was used on the Sioux.[5]

Variants

Military

YR-13/HTL-1[note 1][6]
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 evaluated by the U.S. Navy as trainers.
YR-13A
3 YR-13 aircraft winterized for cold-weather testing in Alaska. Redesignated YH-13A in 1948.[7]
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 200 hp (149 kW ) Franklin 6V4-200-C32 engine. Nine built.
H-13B
65 aircraft ordered in 1948 by the U.S. Army.[7] All Army versions were later named Sioux.
YH-13C
One H-13B used as engineering testbed. Fitted with skid undercarriage and open, uncovered tailboom.[7]
H-13C
16 H-13B aircraft converted to carry external stretchers in 1952, with skid landing gear and open tail boom of YH-13C.[7]
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.[7]
OH-13E
H-13D configuration with three-seat aircraft with dual controls. 490 built.[7]
XH-13F/Bell 201 
Modified Bell 47G powered by a Continental XT51-T-3 (Turbomeca Artouste) turboshaft.[7] 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.[8]
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.[8] UH-13Hs were used by the U.S. Air Force.
UH-13J
Two Bell 47J-1 Rangers acquired by the U.S. Air Force for VIP transport of the U.S. President. Originally designated as H-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 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.
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 based on 47G-3B to replace the OH-13H. 265 received by US Army.[8]
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.[8]
Sioux AH.1
General purpose helicopter for the British Army, 50 built by Agusta (Agusta-Bell 47G-3B1) and 250 built by Westland (Westland-Augusta-Bell 47G-3B1).[9]
Sioux HT.2
Training helicopter for the Royal Air Force, 15 built by Westland.

Operators

 Argentina
 Australia

65 Bell 47 Sioux helicopters were in service with both the Australian Army and RAAF from 1960 to 1977.

 Austria
 Brazil
 Canada
 Chile
 Republic of China
 Colombia
 Cuba
 Denmark
 Dominican Republic
 Ecuador
 France
 Gabon
 Germany
 Greece
 Guatemala
 Iceland
 Indonesia
 India
 Israel
 Italy
 Jamaica
 Japan
 South Korea
 Libya
 Madagascar
 Malaysia
 Malta
 Mexico
 New Zealand
 Pakistan
 Paraguay
 Peru
 Philippines
 Senegal
 South Vietnam
 South Yemen
 Spain
 Sri Lanka
 Sweden
 Thailand
 Turkey
 United Kingdom
 United States
 Uruguay
 Venezuela
 Yugoslavia
 Zaire
 Zambia

Survivors

Specifications (Sioux AH.1)

Data from Newark Air Museum,[14] Britains Small Wars.[15]

General characteristics

Performance

Armament

Popular culture

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).[17]

See also

Related development
Aircraft of comparable role, configuration and era

Notes

  1. ^ In the military of the United States, the Bell 47 carried several designations prior to 1962. R-13 was the first designation by the United States Army Air Forces, while the Navy designated their training version as HTL. In 1948, the United States Air Force changed the designation to H-13 which was also adopted by the Army, adding the name Sioux. The Navy and Coast Guard designated utility models as HUL. 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.

References

Footnotes

  1. ^ Gunston American, p. 117
  2. ^ Donald, David, ed. "Bell Model 47". The Complete Encyclopedia of World Aircraft. Barnes & Nobel Books, 1997. ISBN 0-7607-0592-5.
  3. ^ a b Pearcy, Arthur (1989). A History of Coast Guard Aviation. Naval Institute Press. ISBN 0-87021-261-3. 
  4. ^ James 1991, p.55.
  5. ^ a b c "westland sioux — Helicopter Database". http://www.helis.com/database/model/277/. Retrieved 2009-01-17. 
  6. ^ Derek Bridges. "U.S. Military Aircraft and Weapon Designations". http://www.personal.psu.edu/users/d/o/dob104/aviation/us/index.html. Retrieved 2007-04-17. 
  7. ^ a b c d e f g Harding 1990, p.30.
  8. ^ a b c d Harding 1990, p.31.
  9. ^ James 1991, pp.484-485.
  10. ^ FLIGHT International. 23 November 1972. pp. 754. 
  11. ^ [1]
  12. ^ [2]
  13. ^ "Building 5: Helicopters and last propeller fighter". Royal Thai Air Force Museum. http://www.rtaf.mi.th/museum/BLDG5-2.HTM. 
  14. ^ "Newark Air Museum — Westland Sioux AH.1". http://www.bbc.co.uk/nottingham/360/where_to_go/newark_air_museum/two_seat_night_fighter.shtml. Retrieved 2009-01-17. 
  15. ^ "Britains Small Wars". http://www.britains-smallwars.com/Aden/aircraft.html#sioux. Retrieved 2009-01-17. 
  16. ^ U.S. Helicopter Armament Subsystems
  17. ^ University of Toronto Bell 47 Web site project

Bibliography

  • Donald, David (1997). The Complete Encyclopedia of World Aircraft. NY, NY: Barnes & Noble. ISBN 0-7607-0592-5. 
  • Frawley, Gerard (2003). The International Directory of Civil Aircraft, 2003-2004. Fyshwick, ACT, Australia: Aerospace Publications Pty Ltd. ISBN 1-875671-58-7. 
  • Gunston, Bill (1986). American Warplanes. New York: Crown Publishers Inc.. pp. 117. ISBN 0-517-61351-4. 
  • Harding, Stephen (1990). US Army Aircraft since 1947. Shrewsbury, UK: Airlife Publishing. ISBN 1-85310-102-8. 
  • James, Derek N. (1991). Westland Aircraft since 1915. London: Putnam. ISBN 0-85177-847-X. 
  • Mutza, Wayne (1995). H-13 Sioux Mini in Action. Carrollton, TX, USA: Squadron/Signal Publications. 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. 
  • Taylor, Michael John Haddrick (1989). Jane's encyclopedia of aviation. New York: Portland House. ISBN 0517691868. 
  • 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.

External links