H-34 Choctaw

Sikorsky H-34/S-58
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Type	helicopter
Manufacturer	Sikorsky Aircraft
Maiden flight	March 8, 1954.
Primary users	United States Army US Navy
Developed from	H-19 Chickasaw
Variants	Westland Wessex

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UH-34Ds of the US Marines

Sikorsky H-34 in West German Army markings

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Civil S-58T powered by a Pratt & Whitney Canada PT6 turbine twin pack

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Civil S-58T fire fighting with a Bambi Bucket

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An S-58T helitack shuttle on the Bicy Complex Fire in the Big Cypress National Preserve, Florida

The Sikorsky H-34 Choctaw (also known as the Sikorsky S-58) was a military helicopter originally designed for the US Navy for service in the anti-submarine warfare (ASW) role.

Development

The Sikorsky S-58 was developed from the Sikorsky's UH-19 Chickasaw. The aircraft first flew on March 8, 1954. It was initially designated HSS-1 Seabat (in its anti-submarine configuration) and HUS-1 Seahorse (in its utility transport configuration) under the US Navy designation system. Under the US Army's system, also used by the fledgling US Air Force, the helicopter was designated H-34. The US Army applied the name Choctaw to the helicopter. In 1962, under the new unified 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.

135 H-34 were built in the US 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. 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

The U.S. Coast Guard flew these helicopters from 1959 to 1962.

Vietnam

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. However, the approximately twenty Army H-34s that did eventually reach Vietnam proved no more vulnerable to ground fire than any other rotary-wing aircraft in the theater, and the CH-34 successfully carried out missions ranging from combat assault to aeromedical evacuation and general cargo transport.

The US Marine Corps continued to use the H-34 pattern even after the US Army had phased it out. Even after the USMC adopted their own version of the UH-1, the UH-1E, the CH-34s continued to up to and for a period after the Tet Offensive in 1968. Marine Corps H-34s were also among the first gunship helicopters trialed in theatre, being fitted with the Temporary Kit-1 (TK-1), comprised of 4 M60C machineguns 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.

Most of the twenty surviving CH-34 helicopters were turned over to the South Vietnamese during the course of the war, though a few were ultimately reclaimed by the Army prior to the final collapse of the Saigon Government.

Post-Vietnam

The CH-34 Choctaw remained in frontline Army service well into the late 1960s, and was standard equipment in many Army Reserve and National Guard aviation units for considerably longer. Indeed, the last Choctaw was not officially retired until the early 1970s. Sikorsky production ceased in 1970, with 1,800 built.

Foreign Service

The French Navy adopted the SH-34 Seabat in 1955, using the helicopter during the Algerian War of 1956-62.The French Army had earlier modified the H-19 and Piasecki H-21 with rockets and machine guns for use in a ground attack role; the French Navy performed the same modification to the CH-34 which was developed under the name "Pirate" and was extensively used in counter-insurgency airborne operations. The H-19 proved underpowered for the ground attack role, and the H-21 lacked mobility. The H-34 was able to carry more armament, including a MG151 20 mm cannon firing from the cabin door, two M2 12.7 mm machine guns firing from the cabin windows to port, and batteries of 37- or 68-mm rockets. 73 mm rockets and additional machine guns were also employed on some versions. Official evaluations at the time had indicated that the CH-21 was more likely to survive multiple hits by ground fire than was the CH-34; this was assumed to be a consequence of the location and construction of the CH-34's fuel tanks.

Civilian Use

• The H-34's lift capacity was just sufficient enough to lift a Mercury capsule. In 1961 the hatch of Mercury 4 was untimely detached and the capsule was filled with seawater. That extra weight was too much for the H-34 and Liberty Bell 7 was emergency released (in the deep sea).
• In the 1990s, an S-58ET called Miss Piggy from "New York Helicopter" flew passengers from J.F.Kennedy Int. Airport to East 34th Street Heliport, Manhattan.

H-34 have been used by forest firefighting contractors in Ontario.

Variants

H-34A

US Army version of the HSS-1 powered by a 1525hp R-1820-84, redesignated CH-34A in 1962, 359 built and 21 transferred from the US Navy.

JH-34A

Designation for H-34A used for weapon tests.

VH-34A

Staff transport conversions of H-34A.

H-34B

H-34As converted with detail changes, became CH-34B in 1962.

H-34C

H-34B design with detail changes converted from H-34As, became CH-34C in 1962.

JH-34C

Designation for CH-34C used for weapon tests.

VH-34C

Staff transport conversions of CH-34C.

HH-34D

Designation applied to aircraft given USAF serials to be transferred under MAP and MDAP.

LH-34D

HUS-1L redesignated in 1962

UH-34D

HUS-1 redesignated in 1962 and 54 new build.

VH-34D

HUS-1Z redesignated in 1962

UH-34E

HUS-1A redesignated in 1962

HH-34F

HUS-1G redesignated in 1962

YSH-34G

YHSS-1 redesignated in 1962

SH-34G

HSS-1 redesignated in 1962

SH-34H

HSS-1F redesignated in 1962

YSH-34J

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SH-34Js on the USS Essex in 1962

YHSS-1N redesignated in 1962

SH-34J

HSS-1N redesignated in 1962

UH-34J

SH-34J without ASW equipment for cargo and training purposes.

HH-34J

Ex-USN UH-34Js operated by the US Air Force

VH-34J

Staff transport conversions of SH-34J.

XHSS-1 Seabat

Three Sikorsky S-58s for evaluation by the US Navy, redesignated YHSS-1 then YSH-34G in 1962.

HSS-1 Seabat

Production Anti-Submarine model for the US Navy, redesignated SH-34G in 1962, 215 built

HSS-1F Seabat

One HSS-1 re-engined with two YT-58-GE as a flying test bed, redesignated SH-34H in 1962.

YHSS-1N Seabat

One HSS-1 converted as the HSS-1N prototype, redesignated YSH-34J in 1962.

HSS-1N Seabat

Night/Bad weather version of the HSS-1 with improved avionics and autopilot, redesignated 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 US Marine Corps, redesignated UH-34D in 1962, 462 built

HUS-1A Seahorse

Forty HUS-1s fitted with amphibious pontoons, redesignated UH-34E in 1962.

HUS-1G Seahorse

United States Coast Guard version of the HUS-1, redesignated HH-34F in 1962, six built.

HUS-1L Seahorse

Four HUS-1s converted for antarctic operations with VXE-6, redesignated LH-34D in 1962.

HUS-1Z Seahorse

Seven HUS-1s fitted with VIP interior for the Executive Flight Detachment, redesignated VH-34D in 1962.

S-58

Commercial designation for basic cargo variant

S-58B

Commercial designation for improved cargo variant

S-58C

Commercial passenger transport/airliner version

S-58D

Commercial airliner/freighter version

S-58T

Commercial conversions to turboshaft power by Sikorsky, Orlando Helicopter, and California Helicopter.

S-58 Heli-Camper

Commercial conversion, fitted with a Wright Cyclone R-1820-24 engine.

Orlando Airliner

Commercial conversion. 18-seat passenger transport helicopter.

Operators

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• Template:Country data Katanga
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• Template:PHI
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• Template:Country data South Vietnam
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• Template:USA: USAF, US Army, US Marines, US Navy, US Coast Guard
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Specifications (H-34 Choctaw)

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: 2463 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, hp (kW)

Performance

• Maximum speed: 123 mph (107 kn, 198 km/h)
• Range: 293 km (182 mi)

Armament

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

See also

Related development

• Sikorsky H-19
• Four obsolete H34-J were used in the construction of the Piasecki PA-97 Helistat

Related lists

• List of military aircraft of the United States
• List of helicopters
• List of civil aircraft

References

Bibliography

• Duke, R.A., Helicopter Operations in Algeria [Trans. French], Dept. of the Army, 1959.
• Leuliette, Pierre. St. Michael and the Dragon: Memoirs of a Paratrooper, New York: Houghton Mifflin, 1964.
• Riley, David. "French Helicopter Operations in Algeria." Marine Corps Gazette, February 1958, p. 21-26.
• Shrader, Charles R. The First Helicopter War: Logistics and Mobility in Algeria, 1954-1962. Westport, CT: Praeger Publishers, 1999. ISBN 0-275-96388- 8.
• Spenser, Jay P. Whirlybirds: A History of the U.S. Helicopter Pioneers. Seattle, WA: University of Washington Press, 1998. ISBN 0-29597-699-3.

External links

Wikimedia Commons has media related to:

H-34 Choctaw

• CH-34 US Army Aviation history fact sheet
• Sikorsky H-34 Choctaw on shanaberger.com

This article is licensed under the GNU Free Documentation License. It uses material from the Wikipedia article "H-34 Choctaw".