Sikorsky HH-52 Seaguard

Last updated
HH-52 Seaguard
HH-52A Seaguard with rescue basket (cropped).jpg
A U.S. Coast Guard HH-52A Seaguard helicopter
General information
TypeSAR/utility helicopter
National originUnited States
Manufacturer Sikorsky Aircraft
StatusRetired in 1989
Primary user United States Coast Guard
Number built175
History
Introduction date1961
First flight14 May 1958

The Sikorsky HH-52 Seaguard (company designation S-62) is an early amphibious helicopter designed and produced by American helicopter manufacturer Sikorsky Aircraft. It was the first of the company's amphibious rotorcraft to fly and the United States Coast Guard's first turbine-powered helicopter and first amphibious helicopter. [1]

Contents

The S-62 was originally developed as a commercial venture during the late 1950s. It combined the dynamic elements of the Sikorsky S-55 with a boat hull-shaped fuselage and a single lightweight turboshaft engine. The prototype S-62 conducted its maiden flight on 22 May 1958, powered by a single General Electric T58-GE-6 turboshaft engine. It underwent evaluation at the Naval Air Test Center in Patuxent River, Maryland, at Sikorsky's own expense as part of its effort to promote the S-62 to the United States Coast Guard (USCG).

The USCG would procure 99 S-62s, [1] which it initially designated as the HU2S-1G Seaguard, and later redesignated as the HH-52A Seaguard. It was primarily operated by the USCG for air-sea rescue missions. Various other operators opted to procure the S-62 for their own purposes, from airliners to utility transporters, and foreign air services. It was widely used into the 1980s, when many operators elected to replace the type with newer rotorcraft. The HH-52 was withdrawn from USCG service during 1989 in favor of nonamphibious rotorcraft, such as the Eurocopter HH-65 Dolphin, which rely solely on the use of a winch from a low hover to conduct rescue operations.

Development

A Sikorsky S-62 prototype, circa 1962 Sikorsky S-62 prototype in flight c1962.jpg
A Sikorsky S-62 prototype, circa 1962

Development of the S-62 was launched by Sikorsky during the late 1950s; the initiative was initially pursued as an independent commercial venture. [2] In concept, the project combined the dynamic elements of the earlier Sikorsky S-55 with a boat hull-shaped fuselage and a single lightweight turboshaft engine. [2] This was a relatively ambitious design for the era, being the first of Sikorsky's amphibious helicopters. [3]

A S-62 Prototype, in Le Bourget Airport, June 1959 S62 proto LBG 6-1959.jpg
A S-62 Prototype, in Le Bourget Airport, June 1959

On 14 May 1958, the prototype S-62 performed its maiden flight; in doing so, it had beat its larger Sikorsky S-61 sibling into flight by almost a year. [4] This prototype was powered by a single General Electric T58-GE-6 turboshaft that had been derated from 1,050 hp to 670 hp, powering identical main and tail rotors to those of the S-55.

At Sikorsky's own expense, it funded a "fly before you buy" test program at the Naval Air Test Center in Patuxent River, Maryland; the company actively promoted the type to the United States Coast Guard (USCG) in particular. [2] The results of this test program was largely positive, confirming Sikorsky's performance claims and its suitability for the service. Accordingly, on 21 June 1962, Sikorsky was issued an initial production contract for the type. [2] On 9 January 1963, the first of 99 production helicopters was delivered to the USCG. On 17 January 1969, the final example were delivered by the company. [2]

Design

HH-52 Seaguard with rescue basket lowered HH-52A Seaguard with rescue basket 1960s.jpg
HH-52 Seaguard with rescue basket lowered

Perhaps the most prominent feature of the S-62 is its boat hull fuselage, which was more compact, but otherwise similar to the preceding Sikorsky S-61 (adopted by the US Navy as the SH-3 Sea King). This fuselage is watertight, facilitating landings on water and snow alike, and furnished with two outrigger floats that help the rotorcraft resist both pitching and rolling motions while on the water's surface. These outrigger floats also accommodated the landing gear, which was retractable. [3] To maintain its position while on the water, it was able to deploy an anchor. [5]

Although the S-62 bore little visual resemblance to the Sikorsky S-55, it used many of the same components. [3] It was powered by a single General Electric T58-GE-8B turboshaft engine, capable to generating up to 1,250 hp (930 kW); it was a derated version of the T58-GE-10 powerplant used on the larger, twin-engined SH-3. The S-62 had sufficient power to carry up to 12 passengers, or six litters, along with a crew of three. [3]

Operational history

Two HH-52A helicopters in 1987 HH-52As from CGAS Barbers Point in flight 1987.JPEG
Two HH-52A helicopters in 1987

One prominent early use of the S-62 was with the operator San Francisco and Oakland Helicopter Airlines, one of the first helicopter airlines to operate without a federal subsidy, [6] and the first to operate exclusively using turbine engine helicopters; the airline commenced passenger flights using a pair of two leased S-62s in June 1961, each of which being configured to carry up to 10 passengers. [7] [8] On 21 December of that year, rival operator Los Angeles Airways performed the first scheduled service using an American turbine-powered helicopter via a leased S-62. [9] By June 1962, three S-62s were reportedly in operation for specialized transportation purposes, such as servicing offshore oil rigs in the Gulf of Mexico, with Petroleum Helicopters. [10] Other early civilian operators included Okanagan Helicopters, which used its S-62s to supply remote radar installations, and the Canadian Department of Transport, which had the type fly resupply missions to its lighthouses. [11]

HH-52A, in 1986 HH-52A from USCGC Northwind (WAGB-282) 1986.JPEG
HH-52A, in 1986

A large fleet of 99 S-62s was purchased by the US Navy's Bureau of Aeronautics on behalf of the USCG, who operated the type primarily for search and rescue missions. It was initially designated HU2S-1G Seaguard, but was redesignated as the HH-52A Seaguard in 1962. The HH-52 was commonly dispatched aboard the USCG's larger cutters and icebreakers. The turbine-powered helicopter could carry greater payloads and fly faster than many preceding aircraft, such as the H-19 (S-55). Being designed to be amphibious, the installation of additional flotation gear was not required for over-water flights, and rescues could be conducted by simply landing on the water. Water pickups were considered to be quicker than hoisting survivors up to the helicopter. [2]

Across its services life, the HH-52 fleet played an active role during various emergencies and other circumstances. [2] During the aftermath of Hurricane Betsey in 1965, the type rescued 1,200 people. The HH-52 was periodically used to provide logistical support in Antarctica. [2] One HH-52 was present for the foundering of the oil tanker Burmah Agate on 1 November 1979, facilitating in the rescue of personnel from the affected vessels. [5]

The HH-52 fleet was active for a total of 26 years, during which it reportedly was responsible for saving in excess of 15,000 people from various forms of life-threatening situations. [2] Having been eclipsed by newer rotorcraft, the final flight of a HH-52 took placed on 12 September 1989, after which the type was officially withdrawn from USCG service. [5] [2] It was primarily replaced by the Eurocopter HH-65 Dolphin, a conventional nonamphibious helicopter. [12]

Variants

U.S. Coast Guard HH-52A floating in Seattle in 1979 HH-52A PortAngelesWA NAN6-79.jpg
U.S. Coast Guard HH-52A floating in Seattle in 1979
S-62
Prototype. First flew on 14 May 1958.
S-62A
Amphibious transport helicopter, powered by a General Electric CT58-110-1 turboshaft engine, with accommodation for up to 11 passengers. The S-62A was the first production version.
S-62B
One S-62 was fitted with the main rotor system of the Sikorsky S-58.
S-62C
Company designation of the HH-52A Seaguard.
S-62J
Produced under license in Japan by Mitsubishi. [13]
HU2S-1G
Original designation of the HH-52A Seaguard. Redesignated HH-52A in 1962.
HH-52A Seaguard
Search and rescue helicopter for the United States Coast Guard; 99 built including 1 transferred to Iceland.

Operators

Military/Government

A Coast Guard Grumman HU-16 Albatross and a Sikorsky HH-52A in March 1964 AC HH52 HU16 1.jpg
A Coast Guard Grumman HU-16 Albatross and a Sikorsky HH-52A in March 1964
A S-62J of the Japan Maritime Self-Defense Force S-62.jpg
A S-62J of the Japan Maritime Self-Defense Force
Flag of Japan.svg  Japan
Flag of the Philippines.svg  Philippines
Flag of the United States (23px).png  United States
Flag of Iceland.svg  Iceland
Flag of Thailand.svg  Thailand

Civilian

Flag of Qatar.svg  Qatar
Flag of the United States (23px).png  United States

Aircraft on display

HH-52A Seaguard 'USCG1355' at the National Museum of Naval Aviation in Pensacola, Florida Hh-52a krj.JPG
HH-52A Seaguard 'USCG1355' at the National Museum of Naval Aviation in Pensacola, Florida
Cockpit of HH-52A Seaguard 'USCG1355' at the National Museum of Naval Aviation in Pensacola Hh52cockpitkrj.JPG
Cockpit of HH-52A Seaguard 'USCG1355' at the National Museum of Naval Aviation in Pensacola
An HH-52 Seaguard on display at the Udvar-Hazy Center 20180328 HH-52 Seaguard Udvar-Hazy.jpg
An HH-52 Seaguard on display at the Udvar-Hazy Center

While the type remains in service, a number of Seaguards are on display at museums around the world:

Japan

United States

Philippines

An HH-52 Seaguard on static display at the Philippine Air Force Aerospace Museum in Manila VillamorMuseumjf0803 44.JPG
An HH-52 Seaguard on static display at the Philippine Air Force Aerospace Museum in Manila

South Africa

Thailand

Specifications (HH-52A)

Sikorsky HH-52 Seaguard Line Drawing.svg

Data fromJane's All The World's Aircraft 1969–70 [55]

General characteristics

Performance

See also

HH-52A in a lake, 1964 HH-52A Lake Ponchartrain 1964.jpg
HH-52A in a lake, 1964

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References

Citations

  1. 1 2 "Sikorsky HH-52A Seaguard | National Air and Space Museum". airandspace.si.edu. Retrieved 2024-06-23.
  2. 1 2 3 4 5 6 7 8 9 10 "Sikorsky HH-52A Seaguard". history.uscg.mil. 22 October 2020. Retrieved 1 August 2022.
  3. 1 2 3 4 McGowen 2005, p. 84.
  4. ↑ McGowen 2005, pp. 84, 118.
  5. 1 2 3 4 Ruane, Michael E. (4 March 2016). "The story of the helicopter that saved 22 sailors from burning ships was forgotten. Until now". Washington Post . Retrieved 2 June 2017.
  6. ↑ Chiles, James R. The God Machine: From Boomerangs to Black Hawks: The Story of the Helicopter. p. 218.
  7. ↑ "New Helicopter Service". Flying. Vol. 69, no. 2. August 1961. p. 8. ISSN   0015-4806.
  8. ↑ Boyes, Lindy (December 1961). "San Francisco & Oakland Helicopter Airlines". Flying. Vol. 69, no. 6. p. 44. ISSN   0015-4806.
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  10. ↑ "Big Business". Flying. Vol. 70, no. 6. June 1962. pp. 32–33. ISSN   0015-4806.
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  13. ↑ "Mitsubishi S-62J - Helicopter Database". helis.com. 30 June 2012. Archived from the original on 30 June 2012.
  14. 1 2 "World Helicopter Market 1968". p. 53. Retrieved 25 February 2013.
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  30. ↑ "Aircraft". USS Alabama Battleship Memorial Park. 5 January 2017. Retrieved 2 June 2017.
  31. ↑ "Sikorsky S-62 / HH 52A Sea Guardian". American Helicopter Museum & Education Center. Archived from the original on 9 August 2017. Retrieved 2 June 2017.
  32. ↑ "Airframe Dossier – Sikorsky HH-52A Seaguard, s/n 1383 USCG, c/n 62-064". Aerial Visuals. AerialVisuals.ca. Retrieved 2 June 2017.
  33. ↑ "SIKORSKY HH-52A "SEAGUARD"". Mid-Atlantic Air Museum. Archived from the original on 9 July 2017. Retrieved 2 June 2017.
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  40. ↑ Connor, Roger (14 March 2016). "Celebrating the Centennial of Coast Guard Aviation with the Seaguard". Smithsonian National Air and Space Museum. Retrieved 2 June 2017.
  41. ↑ "Phoenix Project". Coast Guard Aviation Association. Retrieved 2 June 2017.
  42. ↑ "Sikorsky HH-52A (S-62A) 'Seaguard'". New England Air Museum. Archived from the original on 26 July 2017. Retrieved 2 June 2017.
  43. ↑ "Aircraft COLLECTION". Intrepid Sea, Air & Space Museum Complex. Archived from the original on 19 December 2015. Retrieved 2 June 2017.
  44. ↑ "Airframe Dossier - Sikorsky HH-52A Seaguard, s/n 1429 USCG, c/n 62-117". Aerial Visuals. AerialVisuals.ca. Retrieved 2 June 2017.
  45. ↑ "SEAGUARD". Pima Air & Space Museum. PimaAir.org. Archived from the original on 21 September 2017. Retrieved 2 June 2017.
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  47. ↑ Kukulka, Alexandra (10 June 2016). "Organizations seek new home for Naval Air Station Glenview Museum". Chicago Tribune. Retrieved 2 June 2017.
  48. ↑ "Airframe Dossier – Sikorsky HH-52A Seaguard, s/n 1459 USCG, c/n 62.138". Aerial Visuals. AerialVisuals.ca. Retrieved 2 June 2017.
  49. ↑ "HH-52 Helicopter". Naval Air Station Wildwood Aviation Museum. NASW Aviation Museum. Archived from the original on 9 August 2017. Retrieved 2 June 2017.
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  51. ↑ "HH-52 SEAGUARD". Selfridge Military Air Museum. Archived from the original on 10 September 2017. Retrieved 2 June 2017.
  52. ↑ "Airframe Dossier – Sikorsky HH-52A Seaguard, s/n 1466 USCG, c/n 62145". Aerial Visuals. AerialVisuals.ca.
  53. ↑ "Airframe Dossier – Sikorsky HH-52A Seaguard, s/n 62018 PhiAF, c/n M62-018". Aerial Visuals. AerialVisuals.ca. Retrieved 2 June 2017.
  54. ↑ "c/n 62-062". helis.com. Retrieved 2 June 2017.[ unreliable source? ]
  55. ↑ Taylor 1969, pp. 434–434.
  56. 1 2 3 Sikorsky Preflight Reference Cards
  57. ↑ Lednicer, David. "The Incomplete Guide to Airfoil Usage". m-selig.ae.illinois.edu. Retrieved 16 April 2019.

Bibliography

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