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Sikorsky H-34 / S-58
Role Helicopter
Manufacturer Sikorsky Aircraft
First flight 8 March 1954
Introduction 1954
Status out of production, still in civilian service
Primary users United States Army
United States Navy
United States Marines
Number built 2,108
Developed from H-19 Chickasaw
Variants Westland Wessex

The Sikorsky H-34 Choctaw (company designation S-58) is a piston-engined military helicopter that was originally designed by American aircraft manufacturer Sikorsky for the United States Navy for service in the anti-submarine warfare (ASW) role. It has seen extended use when adapted to turbine power by the British licensee as the Westland Wessex and Sikorsky as the later S-58T. Various H-34s served, mostly as medium transports, on every continent with the armed forces of twenty-five countries — from combat in Algeria, the Dominican Republic, Nicaragua, and throughout Southeast Asia, in roles such as saving flood victims, recovering astronauts, fighting fires, and carrying presidents. As one of the last piston-powered helicopter designs before its replacement by turbine-powered types such as the UH-1 Huey and CH-46 Sea Knight, it would see a remarkably long run of 2,108 H-34s produced between 1953 and 1970.[1]


A U.S. Navy HSS-1 with the sonar deployed, in 1960.

CH-37C and UH-34D of the United States Marine Corps.

The Sikorsky S-58 was developed as a lengthened and more powerful version of the Sikorsky (model S-55) or UH-19 Chickasaw, with a similar nose, but with a tail-dragger rear fuselage and landing gear, rather than the high-tail, 4-post pattern. It retained the nose-mounted piston engine with the drive shaft passing through the cockpit placed high above the cargo compartment. The aircraft first flew on 8 March 1954. The first production aircraft was ready in September and entered in service for the United States Navy initially designated HSS-1 Seabat (in its anti-submarine configuration) and HUS-1 Seahorse (in its utility transport configuration) under the U.S. Navy designation system for U.S. Navy, United States Marine Corps (USMC) and United States Coast Guard (USCG) aircraft. The U.S. Army and Marine Corps, respectively, ordered it in 1955 and 1957. Under the United States Army's aircraft designation system, also used by the United States Air Force, the helicopter was designated H-34. The U.S. Army also applied the name Choctaw to the helicopter. In 1962, under the new unified DoD aircraft designation system, the Seabat was redesignated SH-34, the Seahorse as the UH-34, and the Choctaw as the CH-34.

Roles included utility transport, anti-submarine warfare, search and rescue, and VIP transport. In it standard configuration transport versions could carry 12 to 16 troops, or eight stretcher cases if utilized in the MedEvac role, while VIP transports carried significantly fewer people in significantly greater comfort.

A total of 135 H-34s were built in the U.S. and assembled by Sud-Aviation in France, 166 were produced under licence in France by Sud-Aviation for the French Air Force, Navy and Army Aviation (ALAT).

The CH-34 was also built and developed under license from 1958 in the United Kingdom by Westland Aircraft as the turbine engined Wessex which was used by the Royal Navy and Royal Air Force. The RN Wessex was fitted out with weapons and ASW equipment for use in an antisubmarine role. The RAF used the Wessex, with turboshaft engines, as an air/sea rescue helicopter and as troop transporter. Wessexes were also exported to other countries and produced for civilian use.

Operational history

A U.S. Coast Guard HUS-1G in 1960.

Vietnam War

French evaluations on the reported ground fire vulnerabilities of the CH-34 may have influenced the U.S. Army's decision to deploy the CH-21 Shawnee to Vietnam instead of the CH-34, pending the introduction into widespread service of the Bell UH-1 Iroquois. U.S. Army H-34s did not participate in Vietnam, and did not fly in the assault helicopter role, however a quantity were supplied to the Army of the Republic of Vietnam. These saw little use due to a lack of spare parts and maintenance.[2]

U.S. Marine Corps UH-34Ds over Mekong Delta.

U.S. Marine Corps UH-34Ds over Vietnam, 1965.

Its higher availability and reliability due to its simplicity compared to the newer helicopters led Marines to ask for it by name. The phrases "give me a HUS", "get me a HUS" and "cut me a HUS" entered the U.S. Marine Corps vernacular, being used even after the type was no longer in use to mean "help me out".[3] USMC H-34s were also among the first gunship helicopters trialled in theatre, being fitted with the Temporary Kit-1 (TK-1), comprising two M60C machine guns and two 19-shot 2.75 inch rocket pods. The operations were met with mixed enthusiasm, and the armed H-34s, known as "Stingers" were quickly phased out. The TK-1 kit would form the basis of the TK-2 kit used on the UH-1E helicopters of the USMC.

Post-Vietnam War

The H-34 remained in service with United States Army and Marine Corps aviation units well into the late 1960s, and was standard equipment in Marine Corps Reserve, Army Reserve and Army National Guard aviation units until replaced by the UH-1 Iroquois utility helicopter. Sikorsky production ceased in 1968, with 1,821 built.[4] On 3 September 1973, the last flight of a USMC UH-34 occurred as Bureau Number 147191 was flown to MCAS New River.[5] All H-34 helicopters were retired from service in the U.S. military by the early 1970s.


France bought 134 Choctaws in parts from the United States and assembled by Sud-Aviation. A further 166 were manufactured later locally for the French Army, Navy and Air force, these again produced by Sud-Aviation.[6]

Wessex at Ascension Island 1982.

United Kingdom

VNAF CH-34As at Tan Son Nhut.

USMC helicopter in Vietnam.

South Vietnam

The H-34 was the primary VNAF helicopter until replaced by the Bell UH-1 Huey.[7]


Israeli Air Force Sikorsky S-58 (1967)

The S-58 flew combat missions after the end of the Six Days War, mainly against Palestinians infiltrating Israel or against their bases in Jordan. On 21 March 1968, they participated in the Battle of Karameh, bringing Israeli troops in and out as well as evacuating the wounded. This was the last operation of the S-58 as it was retired shortly later, replaced by the Bell 205 and Aérospatiale Super Frelon.[8]

Civilian use

Civil S-58T powered by a Pratt & Whitney Canada PT6T Twin-Pac turbine power plant

  • The H-34's lift capacity was just sufficient to lift a Mercury space capsule. In 1961, the hatch of Mercury-Redstone 4 was prematurely detached and the capsule was filled with seawater. The extra weight was too much for the H-34 and the capsule, Liberty Bell 7, was emergency released and sank in deep water.[9]
  • In the 1990s, an S-58ET called Miss Piggy from "New York Helicopter" flew passengers from JFK International Airport to East 34th Street Heliport, New York.[10]
  • H-34 have been used by forest firefighting contractors in Ontario.
  • At least one S-58 was purchased for civilian use by Oregon-based Columbia Helicopters in the 1960s.[11]
  • In 1968, an S-58 was used to remove the wreckage of a Bell 47 G2 helicopter from the top of Uluru (Ayers Rock) in central Australia.
  • The 1980s television series Riptide featured an S-58T called "The Screaming Mimi".[12] The special turbine engine cowling, together with a "face" paint scheme was used to good effect.


U.S. Army version of the HSS-1 powered by a 1,525 hp R-1820-84, re-designated CH-34A in 1962, 359 built and 21 transferred from the U.S. Navy.
Designation for H-34A used for weapon tests.
Staff transport conversions of H-34A.
H-34As converted with detail changes, became CH-34B in 1962.
H-34B design with detail changes converted from H-34As, became CH-34C in 1962.
Designation for CH-34C used for weapon tests.
Staff transport conversions of CH-34C.
Designation applied to aircraft given USAF serials to be transferred under MAP and MDAP.
HUS-1L re-designated in 1962
HUS-1 re-designated in 1962 and 54 new build.
HUS-1Z re-designated in 1962
HUS-1A re-designated in 1962
HUS-1G re-designated in 1962
YHSS-1 re-designated in 1962
HSS-1 re-designated in 1962
HSS-1F re-designated in 1962

SH-34Js on the USS Essex in 1962

YHSS-1N re-designated in 1962
HSS-1N re-designated in 1962
SH-34J without ASW equipment for cargo and training purposes.
Ex-USN UH-34Js operated by the U.S. Air Force
Staff transport conversions of SH-34J.
XHSS-1 Seabat
Three Sikorsky S-58s for evaluation by the U.S. Navy, re-designated YHSS-1 then YSH-34G in 1962.
HSS-1 Seabat
Production Anti-Submarine model for the U.S. Navy, re-designated SH-34G in 1962, 215 built
HSS-1F Seabat
One HSS-1 re-engined with two YT-58-GE as a flying test bed, re-designated SH-34H in 1962.
YHSS-1N Seabat
One HSS-1 converted as the HSS-1N prototype, re-designated YSH-34J in 1962.
HSS-1N Seabat
Night/Bad weather version of the HSS-1 with improved avionics and autopilot, re-designated SH-34J in 1962, 167 built (an addition 75 HSS-1 airframes were built to CH-34C standard for West Germany).
HUS-1 Seahorse
Utility transport version of the HSS-1 for the U.S. Marine Corps, re-designated UH-34D in 1962, 462 built
HUS-1A Seahorse
Forty HUS-1s fitted with amphibious pontoons, re-designated UH-34E in 1962.
HUS-1G Seahorse
United States Coast Guard version of the HUS-1, re-designated HH-34F in 1962, six built.
HUS-1L Seahorse
Four HUS-1s converted for antarctic operations with VXE-6, re-designated LH-34D in 1962.
HUS-1Z Seahorse
Seven HUS-1s fitted with VIP interior for the Executive Flight Detachment, re-designated VH-34D in 1962.
Commercial designation for basic cargo variant
Commercial designation for improved cargo variant
Commercial passenger transport/airliner version
Commercial airliner/freighter version
Commercial conversion to turboshaft power by Sikorsky, Orlando Helicopter, and California Helicopter. Kit uses Pratt & Whitney Canada PT6T-3 Twin-Pac turboshaft with special nose cowling featuring distinctive twin rectangular air intakes.
S-58 Heli-Camper
Commercial conversion, fitted with a Wright Cyclone R-1820-24 engine.
Orlando Airliner
Commercial conversion. 18-seat passenger transport helicopter.
Westland Wessex
Licence production and development in the United Kingdom.


 Costa Rica
 West Germany
 South Vietnam
 Republic of China
United States

Accidents and incidents

  • 27 July 1960 Chicago Helicopter Airways Flight 698 a S-58C registered N879 crashed into Forest Home Cemetery, Forest Park, Illinois, United States with the loss of 11 passengers and two crew. The investigation concluded that the helicopter became uncontrollable as a result of structural disintegration in flight caused by a fatigue failure of the main rotor blade.[36]
  • 13 March 2011 Sikorsky S-58ET, N33602, suffered an engine failure, descended and veered off the side of an office building in El Segundo, California, while lifting an external load from the roof. The commercial pilot was seriously injured, the helicopter was substantially damaged and consumed by a post-impact fire. The helicopter was registered to Heli Flight, Inc., and operated by Aris Helicopters.[37]

Aircraft on display

Sikorsky UH-34D Seahorse in National Air and Space Museum

Specifications (H-34 Choctaw)

Sikorsky SH-34 orthographical image.svg

General characteristics

  • Crew: 2
  • Capacity: 16 troops or 8 stretchers
  • Length: 56 ft 8.5 in (17.28 m)
  • Rotor diameter: 56 ft 0 in (17.07 m)
  • Height: 15 ft 11 in (4.85 m)
  • Disc area: 2,463 ft² (228.85 m²)
  • Empty weight: 7,900 lb (3,583 kg)
  • Max. takeoff weight: 14,000 lb (6,350 kg)
  • Powerplant: 1 × Wright R-1820-84 radial engine, 1,525 hp (1,137 kW)


  • Maximum speed: 123 mph (107 kn, 198 km/h)
  • Range: 293 km (182 mi)
  • Service ceiling: 4,905 ft (1,495 m[48])


  • Various (See Main Article: U.S. Helicopter Armament Subsystems)
  • See also



    1. "H-34." Retrieved: 30 December 2010.
    2. Mesko 1984, pp. 4–6.
    3. Fails 1995, p. 9.
    4. Endres, Günter G. Jane's Helicopter Markets and Systems. Coulsdon, Surrey, UK: Jane's Information Group, 1996. ISBN 978-0-7106-1363-9.
    5. Fails 1995, p. 127.
    6. "Sikorsky H-34 / CH-34 Choctaw." Retrieved: 17 January 2011.
    7. The Vietnamese Air Force, 1951-1975. An Analysis of Its Role in Combat and Fourteen Hours at Koh Tang. Volume 3, USAF Southeast Asia monograph series 4 and 5. Washington D.C.: Office of Air Force History, 1985.
    8. Gunston 1982, p. 92.
    9. Wade, Mark. "Mercury MR-4.", 29 April 2009. Retrieved (from archive): 26 July 2011.
    10. Brown, Allan. "S-58ET from New York Helicopter." Retrieved: 17 January 2011.
    11. "History." Columbia Helicopters. Retrieved: 17 January 2011.
    12. "Riptide — helicopter TV show review for Rotary Action at" Pigasus Press, 2005. Retrieved: 5 March 2009.
    13. "Fuerza Aerea Argentina H-58". Retrieved 7-March-2013. 
    14. "World Air Forces 1968 pg. 48". Retrieved 1-March-2013. 
    15. 15.0 15.1 15.2 15.3 "World Air Forces 1968 pg. 49". Retrieved 2013-03-01. 
    16. "Armada de Chile SH-34J". Retrieved 7-March-2013. 
    17. "Sikorsky-HSS-1N-(S-58A)". Demand media. Retrieved 7-March-2013. 
    18. "World's Air Forces 1981 pg. 332". Retrieved 7-March-2013. 
    19. 19.0 19.1 19.2 19.3 "World Air Forces 1968 pg. 51". Retrieved 2013-03-01. 
    20. "World Air Forces 1971 pg. 928". Retrieved 7-March-2013. 
    21. "World's Air Forces 1981 pg. 346". Retrieved 7-March-2013. 
    22. "World's Air Forces 2004 pg. 65". Retrieved 7-March-2013. 
    23. "World Air Forces 1968 pg. 52". Retrieved 1-March-2013. 
    24. "World Air Forces 1968 pg. 52 (m)". Retrieved 1-March-2013. 
    25. "World Air Forces 1971 pg. 932". Retrieved 7-March-2013. 
    26. "World Air Forces 1968 pg. 53". Retrieved 1-March-2013. 
    27. "World Air Forces 1968 pg. 54". Retrieved 1-March-2013. 
    28. "World's Air forces 1981 pg.362". Retrieved 7-March-2013. 
    29. "World Air Forces 1968 pg. 60". Retrieved 1-March-2013. 
    30. "World's Air Forces 1981 pg. 377". Retrieved 7-March-2013. 
    31. "World Air Forces 1968 pg. 55". Retrieved 1-March-2013. 
    32. "US Air ForceH-34". Retrieved 7-March-2013. 
    33. 33.0 33.1 33.2 33.3 "Sikorsky Product History". Retrieved 2013-03-05. 
    34. "USCG History". USCG HH-34. Retrieved 7-March-2013. 
    35. "World's Air Forces 1987 pg. 104". Retrieved 7-March-2013. 
    36. "CAA 429 World Airline Accident Summary with reference to Civil Aeronautics Board Aircraft Accident Report SA-357." United Kingdom CAA Document.
    37. "NTSB Identification: WPR11FA163." Retrieved: 26 July 2011.
    38. "UH-34D Seahorse, Sikorsky." Patriot's Point Naval and Maritime Museum. Retrieved: 26 July 2011.
    39. 39.0 39.1 Royal Thai Air Force Msueum: "Building 5: Helicopters and last propeller fighter.", Retrieved: 17 January 2011.
    40. "Helicopters." Carolinas Aviation Museum. Retrieved: 26 July 2011.
    41. "Sikorsky UH-34J 'Sea Bat'." Wings of Freedom Aviation Museum. Retrieved: 26 July 2011.
    42. "UH-34D Seahorse, Aircraft Carrier USS Hornet Museum." Aircraft Carrier USS Hornet Museum. Retrieved: 28 May 2012.
    43. "Aircraft On Display." National Naval Aviation Museum. Retrieved: 4 September 2012.
    44. O'Connell, Jim. "Pete VX-6." Retrieved: 4 September 2012.
    45. "Sikorsky UH-34D Seahorse." Smithsonian National Air and Space Museum. Retrieved: 21 November 2012.
    46. New England Air Museum: "Sikorsky LH-34D (S-58) 'Seabat'"
    47. Pueblo Weisbrod Aircraft Museum: SH-34J Sea Horse on display, retrieved 16 May 2013
    48. Apostolo 1984, p. 84.


    • Apostolo, Giorgio. The Illustrated Encyclopedia of Helicopters. New York: Bonanza Books, 1984. ISBN 0-517-439352.
    • Duke, R.A. Helicopter Operations in Algeria [Translated French]. Washington, DC: Dept. of the Army, 1959.
    • Fails, William R. Marines & Helicopters, 1962-1973. Darby, Pennsylvania: Diane Publishing, 1995. ISBN 0-7881-1818-8.
    • Gunston, Bill. An Illustrated Guide To the Israeli Air Force. London: Salamander Books, 1982. ISBN 978-0-668-05506-2.
    • Leuliette, Pierre. St. Michael and the Dragon: Memoirs of a Paratrooper, New York: Houghton Mifflin, 1964.
    • Mesko, Jim: Airmobile: The Helicopter War in Vietnam. Carollton, Texas: Squadron/Signal Publications, 1984. ISBN 0-89747-159-8.
    • Riley, David. "French Helicopter Operations in Algeria." Marine Corps Gazette, February 1958, pp. 21–26.
    • Shrader, Charles R. The First Helicopter War: Logistics and Mobility in Algeria, 1954-1962. Westport, Connecticut: Praeger Publishers, 1999. ISBN 0-275-96388-8.
    • Apostolo, Giorgio. The Illustrated Encyclopedia of Helicopters. New York: Bonanza Books, 1984. (page 84) ISBN 0-517-439352.
    • Spenser, Jay P. Whirlybirds: A History of the U.S. Helicopter Pioneers. Seattle, Washington: University of Washington Press, 1998. ISBN 0-295-97699-3.

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