Sikorsky S-61

In September 1957, Sikorsky was awarded a United States Navy development contract for an amphibious anti-submarine warfare (ASW) helicopter capable of detecting and attacking submarines. On 11 March 1959, the XHSS-2 Sea King prototype made its maiden flight. Production deliveries of the HSS-2 (later designated SH-3A) commenced during September 1961. The initial production aircraft was powered by a pair of General Electric T58-GE-8B turboshaft engines, each capable of providing up to {{cvt|930|kW|shp|order=flip}}.McGowen 2005, p. 84.

Sikorsky quickly decided to pursue the development of a dedicated commercial model of the Sea King. Two prime models were produced: the land-based S-61L and the amphibious S-61N.Sikorsky 2007, p. 92. On 2 November 1961, the S-61L conducted its maiden flight; it was {{convert|4|ft|3|in|m|abbr=on}} longer than the HSS-2 to facilitate the carriage of a substantial payload of freight or passengers. Initial production S-61Ls were powered by two {{cvt|1350|shp}} GE CT58-110 turboshafts, the civil version of the T58. The S-61L features a modified landing gear that eliminates the float stabilisers.

On 7 August 1962, the S-61N performed its first flight. Being otherwise identical to the S-61L, this version is optimized for overwater operations, particularly oil rig support, by retaining the SH-3's floats. Both the S-61L and S-61N were subsequently updated to the Mk II standard, which was outfitted with more powerful CT58-140 engines that provided superior performance in hot and high conditions, along with incorporating measures to dampen vibration and various other refinements.

File:Coulson S61 Drop.jpg

Additional civil models of the S-61 would soon be developed. The Payloader, a stripped-down version optimized for aerial crane work, was the third civil model of the S-61 produced. The Payloader features the fixed undercarriage of the S-61L, but with an empty weight almost {{convert|2000|lb|kg|abbr=on}} less than the standard S-61N.

Carson Helicopters was the first company to shorten a commercial S-61. The fuselage is shortened by {{convert|50|in|m|abbr=on}} to increase its single-engine performance and external payload.{{cite web |url = http://www.carsonhelicopters.com/about_carson.htm |title = About Carson Helicopters |access-date = 12 January 2009 |publisher = Carson Helicopters |year = 2009 |archive-date = 31 January 2009 |archive-url = https://web.archive.org/web/20090131074559/http://carsonhelicopters.com/about_carson.htm |url-status = dead }} The improved lift performance lent itself to utility operations, particularly in the construction market.{{cite web |url = https://verticalmag.com/features/helicarrier-dreaming-big/ |title = Helicarrier: Dreaming Big |publisher = verticalmag.com |first = Dan |last = Megna |date = 11 February 2021}}

A unique version is the S-61 Shortsky, a conversion of S-61Ls and S-61Ns performed by Helipro International. VIH Logging was the launch customer for HeliPro's Shortsky, which conducted its first flight during February 1996.{{cite web |url = http://www.flightglobal.com/articles/1996/04/03/17432/helipro-shortsky-enters-service.html |title = Helipro Shortsky enters service |publisher = FlightGlobal |date = 3 April 1996}}

One modification for the S-61 is the Carson Composite Main Rotor Blade. These blades replace the original Sikorsky metal blades, which are prone to fatigue, and permit a modified aircraft to carry an additional {{convert|2000|lb|kg|abbr=on}} load, fly {{convert|15|kn|km/h|0|abbr=on}} faster and increase range {{convert|61|nmi|km|0|abbr=on}}.

During the 2000s, the S-61T modernisation emerged. This model includes composite main rotor blades, a modular wiring harness, and (optionally) a glass cockpit; these changes reportedly boost the helicopter's lift capability and increase its speed. In June 2010, the United States Department of State signed a purchase agreement for 110 modernized S-61Ts, which will perform passenger and cargo transport missions to support its worldwide operations.{{cite web |url = https://verticalmag.com/news/u-s-state-department-accepts-modernized-s-61-helicopters-for-use-in-afghanistan-html/ |title = Press Releases: U.S. State Department Accepts Modernized S-61TM Helicopters for Use in Afghanistan |publisher = verticalmag.com |date = 2 June 2010}}

File:Noodlanding oefening helicopters-518075.ogv

The first civil operator to adopt the S-61 was Los Angeles Airways, which introduced the type to service on 11 March 1962.Apostolo, G. "Sikorsky S-61".The Illustrated Encyclopedia of Helicopters. Bonanza Books, 1984. {{ISBN|0-517-43935-2}}. The company had reportedly bought them from Sikorsky at a unit price of $650,000 each. Sikorsky's foremost competitor in sales was Boeing Vertol, which had a Vertol 107 twin-rotor helicopter, which arrived on the market shortly after the S-61.{{cite web |url = http://www.time.com/time/magazine/article/0,9171,895186,00.html |archive-url = https://web.archive.org/web/20101008110409/http://www.time.com/time/magazine/article/0,9171,895186,00.html |title = The Self-Supporting Helicopter |publisher = Time Magazine |date = 26 December 1960|archive-date = 2010-10-08 }} While regarded as one of the most successful American scheduled helicopter airlines even by the 21st century, following several accidents involving its S-61s, including the crash of the prototype S-61 N300Y, Los Angeles Airways ceased operations in 1971.

Even before the receipt of approval from the Federal Aviation Administration (FAA), the S-61 had been purchased by several airliners, including Los Angeles Airways, New York Airways, and Chicago Helicopter Airways. It was promoted as the first U.S. helicopter explicitly designed as a commercial airliner. The S-61 seated 25 passengers with an estimated direct operating cost of 8¢ per seat mile. The operating costs of civil helicopters were considered crucial, even before the S-61's introduction, as airlines had typically been unable to achieve profitable helicopter routes and became dependent on government subsidies to operate, reportedly due to the limited capacity and high operating expense of the available helicopters. It was hoped that the S-61 would noticeably improve on economics compared to its predecessors.

New York Airways ordered a batch of ten S-61s to serve its helicopter routes. Perhaps most prominently, it started operating flights from a heliport on the 59-story Pan Am Building, and at one point planned to perform as many as 360 helicopter flights per day. Launched on 21 December 1965, the operation soon proved unprofitable, carrying an average of only eight passengers, leading to the heliport's closure in 1968. While flights were resumed during February 1977, an accident three months later involving an S-61 helicopter that collapsed and flipped onto its side, killing five people, led to the heliport being closed indefinitely. Two years later, New York Airlines ended helicopter operations.{{cite web |url = https://metroairportnews.com/the-history-of-new-york-airways-helicopter-operations/ |title = The History of New York Airways' Helicopter Operations |publisher = metroairportnews.com |first = Robert G. |last = Waldvogel |date = 11 November 2021}}

From 1962 to 1966, Pakistan International Airlines (PIA) operated its Sikorsky S-61 helicopters for services within East Pakistan Helicopter Service (present day Bangladesh) using four S-61s. The helicopter route to Khulna reduced the 21-hour journey overland to 37 minutes by air. 20 towns and cities covered by the network, including Bogra, Sirajganj, Chittagong, Mongla, Kushtia, Barisal, Chandpur, Sandwip and Hatiya Upazila. The average price of a ticket was 25 rupees. It was the world's largest commercial helicopter network at the time.{{cite magazine |url = http://content.time.com/time/magazine/article/0,9171,875483,00.html |title = Asia: Choppers over Pakistan |magazine = Time |date = 13 December 1963 |access-date = 14 September 2017 |via = content.time.com}}

Between 1978 and 1986, an S-61 was used for an Airlink service between the London airports of Heathrow and Gatwick over a distance of {{convert|42|mi|km}}; it was operated jointly by British Caledonian Airways and British Airways Helicopters in partnership with the British Airports Authority (BAA). While the operation proved valuable before the opening of the M25 motorway, its noise led to it being controversial, the route overflying several densely populated areas of London. Initially, the Civil Aviation Authority banned flights between 9:15 pm and 6:30 am to limit its impact, but the whole service came to an end after its licence to operate was revoked by the Transport Secretary on 6 February 1986.{{cite web |url = https://www.getreading.co.uk/news/berkshire-history/airlink-helicopters-helicopter-service-used-23915456 |title = Airlink helicopters: The helicopter service that used to link Heathrow to Gatwick |publisher = getreading.co.uk |first = Dave |last = Doyle |date = 14 May 2022}} Numerous S-61s were also operated on other routes in Britain, often between the mainland and offshore locations such as the Channel Islands, the Scilly Islands, and various oil rigs in the North Sea.Woodley 2006, pp. 8, 103.

File:EC-FZJ.jpg

The British operator Bristow Helicopters operated several S-61s; they performed search and rescue (SAR) operations from civilian bases at Stornoway, Sumburgh, Lee-on-Solent, and Portland between 1983 and 2007.{{cite web |url = https://www.lelezard.com/en/news-6363922.html |title = Sikorsky and Bristow Embark on New Era of Search and Rescue |publisher = PRNewswire |date = 3 March 2015}} Between 1991 and 2013, the Irish Coast Guard operated its own S-61s for SAR operations.

Various government organisations have also adopted the S-61. During the 2010s, the United States Department of State procured in excess of 100 S-61Ts in support of its worldwide operations. These rotorcraft have been operated in Iraq and Afghanistan, amongst other locations.{{cite web |url = https://verticalmag.com/news/u-s-state-department-orders-11-more-upgraded-s-61-helicopters-for-use-in-iraq-afghanistan-html/ |title = U.S. State Department Orders 11 More Upgraded S-61 Helicopters for Use in Iraq & Afghanistan |publisher = verticalmag.com |date = 20 September 2010}}{{cite web |url = https://www.ctpost.com/news/article/Upgraded-Sikorsky-Sea-Kings-on-new-mission-509452.php |title = Upgraded Sikorsky Sea Kings on new mission |publisher = ctpost.com |first = Rob |last = Varnon |date = 3 June 2010}}

;S-61L : Non-amphibious civil transport version. It seats up to 30 passengers.{{cite web |url = http://www.flightglobal.com/pdfarchive/view/1967/1967%20-%200730.html |title = VTOL AIRCRAFT 1967 |page = 712 |publisher = Flightglobal Insight |year = 2015 |access-date = 4 January 2015}}

;S-61L Mk II: Improved version of the S-61L, cabin equipped with cargo bins.{{cite web |url = http://www.flightglobal.com/pdfarchive/view/1971/1971%20-%200177.html |title = CIVIL V/STOL 1971 |page = 162 |publisher= Flightglobal Insight |year = 2015 |access-date = 4 January 2015}}

;{{visible anchor|S-61N}} : Amphibious civil transport version.

;S-61N Mk II: Improved version of the S-61N.

;S-61NM: An L model in an N configuration.{{cite web |url = http://www.faa.gov/regulations_policies/airworthiness_directives/search/?q=&makeModel=&type=Current&filter=&sort=title&direction=desc&startRow=1251 |title = Airworthiness Directives Sikorsky Models S-61L, S-61N, and S-61NM |publisher = faa.gov |access-date = 12 January 2015}}

;S-61T Triton: A modernized upgrade was performed by Sikorsky and Carson Helicopters. Upgrades include composite main rotor blades, full airframe structural refurbishment, conversion of folding rotor head to non-folding, new modular wiring harness, and Cobham-supplied glass cockpit avionics. Initial models converted were S-61N.{{cite web |url = http://www.flightglobal.com/articles/2010/02/21/338633/heli-expo-sikorsky-s-61t-gains-new-life-in-state-department-program.html |title = HELI-EXPO: Sikorsky S-61T gains new life in State Department program |first=John |last=Croft |publisher = Flight Global |date=21 February 2010 |archive-date = 30 December 2010 |archive-url = https://web.archive.org/web/20101230174411/http://www.flightglobal.com/articles/2010/02/21/338633/heli-expo-sikorsky-s-61t-gains-new-life-in-state-department-program.html |url-status = dead }}

;AS-61N-1 Silver: A license-built model of the S-61N by Agusta, with a shortened cabin.

File:Sikorsky S-61N Shortsky, Carson Helicopters AN0263247.jpg Sikorsky S-61N]]

File:HelitankerToodyay December 2009.jpg

;{{CAN}}

• CHC Helicopter{{cite web |url = http://www.chc.ca/AboutCHC/Fleet/Pages/default.aspx |title=CHC Helicopter fleet |publisher = chc.ca |access-date = 17 March 2013 |url-status = dead |archive-url = https://web.archive.org/web/20130213054621/http://www.chc.ca/AboutCHC/Fleet/Pages/default.aspx |archive-date = 13 February 2013 }}
• Cougar Helicopters{{cite web |url = http://www.cougar.ca/Fleet/sikorsky-s61.asp |title = Cougar Helicopters |publisher = cougar.ca |access-date = 17 March 2013 |url-status = dead |archive-url = https://web.archive.org/web/20130824214737/http://cougar.ca/Fleet/sikorsky-s61.asp |archive-date = 24 August 2013}}

;{{GRL}}

• Air Greenland{{cite web |url = http://www.airgreenland.com/about/our-aircraft-and-helicopters/s-61 |title = Air Greenland fleet |publisher = airgreenland.com |access-date = 17 March 2013}}

;{{Flag|Indonesia}}

• National Agency for Disaster Countermeasure{{Cite web |url = https://www.bnpb.go.id/ |title = BNPB Official Website}}

;{{GBR}}

• Bristow Helicopters{{cite web |url = http://www.bristowgroup.com/clients/helicopter-fleet/ |title = Bristow Helicopters fleet |publisher = bristowgroup.com |access-date = 17 March 2013 |archive-date = 22 January 2018 |archive-url = https://web.archive.org/web/20180122001052/http://www.bristowgroup.com/clients/helicopter-fleet/ |url-status = dead }}

;{{ESP}}

• Sociedad de Salvamento y Seguridad Marítima{{cite web |url = http://www.salvamentomaritimo.es/sm/flota-y-medios/medios-aereos/helicopteros-de-salvamento-maritmo/?ids=358 |title = Helicópteros de Salvamento Marítimo |access-date = 19 February 2022 |author = Sociedad de Salvamento y Seguridad Marítima |work = salvamentomaritimo.es |archive-url = https://web.archive.org/web/20120408050431/http://www.salvamentomaritimo.es/sm/flota-y-medios/medios-aereos/helicopteros-de-salvamento-maritmo/?ids=358 |archive-date = 8 April 2012|url-status = dead}}

;{{USA}}

• AAR Corp{{cite web |url = http://www.ainonline.com |title = DOD Contracts Keep U.S. Helicopter Operators Busy in Afghanistan |publisher = ainonline.com |access-date = 4 June 2013}}
• Carson Helicopters{{cite web |url = http://www.carsonhelicopters.com/|title= Carson Helicopters Home page |publisher = carsonhelicopters.com |access-date = 17 March 2013}}{{cite web |url = http://wildfiretoday.com/2013/02/04/former-employees-of-carson-helicopters-indicted-over-fatal-iron-44-fire-crash/ |title = Former employees of Carson Helicopters indicted over fatal Iron 44 Fire crash |date = 4 February 2013 |publisher = wildfiretoday.com |access-date = 17 March 2013}}
• CHI Aviation{{Cite web |url = http://chiaviation.com/fleet/ |title = Fleet |publisher = CHI Aviation |language = en-US |access-date = 20 May 2019}}
• Helimax Aviation{{Cite web |url = http://helimaxaviation.com/fleet/ |title = Fleet |publisher = Helimax Aviation |access-date = 20 May 2019}}
• Croman Corporation{{cite web |url = http://www.croman.net/2005/HeavyLift.htm |title=Croman Corporation Heavy Lift Svc. |publisher = croman.net |access-date = 17 March 2013 |archive-url = https://web.archive.org/web/20130304074349/http://www.croman.net/2005/HeavyLift.htm |archive-date = 4 March 2013 |url-status = dead |df = dmy-all }}
• Helicopter Transport Services {{cite web |url = http://www.htshelicopters.com/aircraft/ |title = Helicopter Transport Services Aircraft |publisher = htshelicopters.com |access-date = 17 March 2013}}
• United States Department of State{{cite web |url = http://www.sikorsky.com/About+Sikorsky/News/Press+Details?pressvcmid=8d8ad02f379f8210VgnVCM1000004f62529fRCRD&keyword=S-61&dateFrom=null&dateTo=null&model=null&business=null&matchCriteria=null&matchKeyword=any&fromSearchPage=true&businessIndex=null&=modelIndex=null |title = Sikorsky |website = www.sikorsky.com |access-date = 14 September 2017 |archive-date = 26 January 2020 |archive-url = https://web.archive.org/web/20200126215427/https://www.lockheedmartin.com/en-us/capabilities/sikorsky.html?pressvcmid=8d8ad02f379f8210VgnVCM1000004f62529fRCRD&keyword=S-61&dateFrom=null&dateTo=null&model=null&business=null&matchCriteria=null&matchKeyword=any&fromSearchPage=true&businessIndex=null&=modelIndex=null |url-status = dead }}

File:G-BDOC S-61N Coastguard (4436275694).jpg S-61N operated by Bristow Helicopters]]

File:British S-61N G-BFRI during exercise Joint Warrior 2014-2.JPG]]

;{{ARG}}

• Argentine Air Force{{Citation needed|date=May 2022}}

;{{Flag|Brunei}}

• Brunei Shell Petroleum{{Cite web |url=https://www.pprune.org/rotorheads/291187-bsp-s-61s-final-departure-end-era.html |title=BSP S-61s final departure - the end of an era |date=7 September 2007 |website=pprune.org}}

;{{CAN}}

• Canadian Coast Guard{{cite web |url =http://helihub.com/2010/12/03/coast-guard-s-61-being-retired-from-duty-in-prince-rupert/ |title = Coast Guard S-61 being retired from duty in Prince Rupert |date = 3 December 2010 |publisher = helihub.com |access-date = 20 March 2013}}
• Helijet

;{{INA}}

• Indonesian Air Force - S-61V{{Cite web |last=Zahir |first=Zahir |date=3 January 2023 |title=Sejarah Hari Ini: Rekam Jejak Helikopter Sikorsky S-61V dalam Kedirgantaraan Indonesia |url=https://yoursay.suara.com/ulasan/2023/01/03/175535/sejarah-hari-ini-rekam-jejak-helikopter-sikorsky-s-61v-dalam-kedirgantaraan-indonesia |access-date=2023-11-21 |website=suara.com |language=id}}{{Cite web |last=Pamungkas |first=Bayu |date=2016-02-01 |title=Sikorsky S-61V: Menelusuri Jejak Helikopter Bung Karno Yang Hilang |url=https://www.indomiliter.com/sikorsky-s-61v-menelusuri-jejak-helikopter-bung-karno-yang-hilang/ |access-date=2023-11-21 |website=Indomiliter.com |language=id}}

;{{IRL}}

• Irish Air Corps{{cite web |url = https://www.irishtimes.com/news/decision-on-80m-air-corps-helicopters-contract-due-soon-1.317361 |title = Decision on £80m Air Corps helicopters contract due soon |website = irishtimes.com |access-date = 22 April 2018}}
• Irish Coast Guard{{cite web |url = http://afloat.ie/safety/coastguard/item/24012-end-of-an-era-as-irish-coast-guards-last-s61-retires |title = End Of An Era As Irish Coast Guard's Last S61 Retires |publisher = afloat.ie |access-date = 12 December 2013}}{{cite news |url = http://www.helis.com/database/modelorg/1441/ |title = Garda Cósta na hÉireann S-61 |newspaper = Helis.com |access-date = 17 March 2013}}

;{{LBN}}

• Lebanese Air Force{{cite web |year = 2021 |title = Lebanon's Air Force launches public aircraft bids as part of fleet reorg|url = https://www.defensenews.com/air/2021/03/29/want-to-buy-fighter-jets-and-helos-lebanon-is-accepting-bids/|publisher = Defense News}}

;{{NLD}}

• KLM Helikopters{{cite web |url = http://www.erahelicopters.com/content/e4/e201/index_eng.html |title = KLM / Era Helicopters history |publisher = erahelicopters.com |access-date = 20 March 2013 |url-status = dead |archive-url = https://archive.today/20130409060343/http://www.erahelicopters.com/content/e4/e201/index_eng.html |archive-date= 9 April 2013 }}{{cite web |url = http://www.airliners.net/photo/KLM-Noordzee-Helikopters/Sikorsky-S-61N-MkII/1376597/L/&sid=2fac8a1a5b8a03a437ebde2806364a25 |title = KLM-Noordzee Helikopters S-61N |publisher = Demand media |access-date = 20 March 2013}}

;{{flag|Norway}}

• Helikopter Service A/S{{cite news |url = https://www.helis.com/database/modelorg/Helikopter-Service-S-61/ |title = Helicopter Service |newspaper = Helis.com |access-date = 26 June 2019}}

;{{PAK}}

• Pakistan International Airlines{{cite web |url = https://www.flightglobal.com/pdfarchive/view/1967/1967%20-%201261.html |title = World Helicopter Market 1967 |page = 63 |publisher = flightglobal.com |access-date = 4 February 2016}}

;{{GBR}}

• British Airways Helicopters{{cite news |url = http://www.helis.com/database/modelorg/1540/ |title = British Airways Helicopters |newspaper = Helis.com |access-date = 17 March 2013}}
• British Caledonian Helicopters{{cite news |url = https://www.helis.com/database/org/uk_british_caledonian_helicopter_ltd/ |title = British Caledonian Helicopters |newspaper = Helis.com |access-date = 26 June 2019}}
• British International Helicopters{{cite news |url = http://www.helis.com/database/modelorg/63/ |title = British International Helicopters S-61 |newspaper = Helis.com |access-date = 17 March 2013}}
• Her Majesty's Coastguard{{cite news |url = http://www.helis.com/database/modelorg/157/ |title = HM Coastguard S-61N |newspaper = Helis.com |access-date = 17 March 2013}}

;{{USA}}

• Los Angeles Airways{{cite web |url = http://www.flightglobal.com/pdfarchive/view/1969/1969%20-%200653.html?search=%22Los%20Angeles%20Airways%22 |title = Flight Int'l 1969 |page = 581 |publisher = flightglobal.com |access-date = 17 March 2013}}
• New York Airways{{cite web |url = http://www.flightglobal.com/pdfarchive/view/1974/1974 |archive-url = https://archive.today/20130123045252/http://www.flightglobal.com/pdfarchive/view/1974/1974%20-%201045.html |url-status = dead |archive-date = January 23, 2013 |title = New York Airways |publisher = flightglobal.com |access-date = 17 March 2013}}
• San Francisco and Oakland Helicopter Airlines{{cite web |url = https://www.flightglobal.com/pdfarchive/view/1968/1968%20-%201213.html |title = World Helicopter Market 1968 |page = 57 |publisher = flightglobal.com |access-date = 5 February 2016}}

File:6308-340DisneyLandChopper-R.jpg ]]

1960s

• On 2 February 1966, Pakistan International Airlines Flight 17, operated by a Sikorsky S-61 helicopter registration AP-AOC, crashed on a scheduled domestic flight in Faridpur Division, East Pakistan after the main gearbox failed, killing 23 of the 24 passengers and crew on board.
• On 10 December 1966, a Pakistan International Airlines Sikorsky S-61 helicopter registration AP-AOA crashed on a scheduled domestic flight in Dhaka, East Pakistan.{{cite web |url = http://www.historyofpia.com/oldfleet.htm |title = PIA helicopter service |access-date = 14 February 2019}}
• On 22 May 1968, Los Angeles Airways Flight 841 crashed near Paramount, California, resulting in the loss of 23 lives. The accident aircraft, N303Y, serial number 61060, was a Sikorsky S-61L en route to Los Angeles International Airport from the Disneyland Heliport in Anaheim, California.
• On 14 August 1968, Los Angeles Airways Flight 417 crashed in Compton, California, while en route to the Disneyland Heliport in Anaheim, California from Los Angeles International Airport, resulting in the loss of 21 lives. The accident aircraft, N300Y, serial number 61031, was the prototype of the Sikorsky S-61L.{{usurped|[https://web.archive.org/web/20080625152435/http://www.airdisaster.com/reports/ntsb/AAR69-07.pdf Aircraft Accident Report. Los Angeles Airways, Inc. S-61L Helicopter, N300Y, Compton, California]}}, Adopted: 27 August 1969{{cite web |url = https://www.forbes.com/sites/michaelgoldstein/2021/10/12/does-the-crash-of-a-disneyland-helicopter-airline-50-years-ago-still-have-lessons-to-teach-today/ |title = Will Disasters Like Disneyland Helicopter Airline And Kobe Crashes Impact EVTOL Future? |work = forbes.com |first = Michael |last = Goldstein |date = 12 October 2021}}

1970s

• On 25 October 1973, a Greenlandair S-61N, OY-HAI "Akigssek" ("Grouse") crashed about {{cvt|40|km|mi|order=flip}} south of Nuuk, resulting in the loss of 15 lives. It was en route to Paamiut from Nuuk. The same aircraft had an emergency landing on the Kangerlussuaq fjord two years earlier, due to flameout on both engines because of ice in the intake.{{cite web|url=http://dokumenter.arktiskleksikon.dk/index.php?id=20&no_cache=1&showUid=812|title=Arktisk dokumentarkiv|publisher=arktiskleksikon.dk|access-date=4 January 2015|url-status=dead|archive-url=https://web.archive.org/web/20141214184147/http://dokumenter.arktiskleksikon.dk/index.php?id=20&no_cache=1&showUid=812|archive-date=14 December 2014}}
• On 10 May 1974 a KLM Helikopters S-61N, registration PH-NZC, crashed en route to an oil rig in the North Sea. None of the six people on board (two crew and four passengers) survived. The probable cause was a failure in one of five rotor blades due to metal fatigue. The resulting imbalance caused the motor mounts to fail and caused a fire. The uncontrollable aircraft landed hard in the water, capsized and sank. Investigation indicated that the metal fatigue crack must have spread rapidly in less than four hours. The rotor blades are pressurized with nitrogen gas at {{cvt|10|psi|lk=in}} to indicate the onset of a metal fatigue failure, yet no pressure loss was indicated during the preflight inspection. As a result of the accident, it was recommended to shorten inspection intervals.{{cite web|url=http://www.hdekker.info/Nieuwe%20map/1974.htm#10.05.1974|title=1974|publisher=hdekker.info|access-date=4 January 2015}} The aircraft was recovered from the North Sea floor. It was sold to Carson Helicopter in the U.S. and re-registered as N87580.{{cite web|url=http://aviation-safety.net/wikibase/wiki.php?id=786|title=ASN Aircraft accident 10-MAY-1974 Sikorsky S-61N PH-NZC|author=Harro Ranter|publisher=aviation-safety.net|access-date=4 January 2015}}
• On 16 May 1977, a New York Airways commercial S-61-L, N619PA, suffered a static rollover onto its starboard side at the heliport on top of the Pan Am Building while boarding passengers. The accident killed four boarding passengers, including filmmaker Michael Findlay, and one woman on the street. Seventeen additional passengers and the three flight crew members were uninjured.UPI. Helicopter Crash Kills Five. Beaver County (Pa.) Times: Tuesday, 17 May 1977, A-13. The landing gear collapse resulted from metal fatigue in the helicopter's main landing gear shock-absorbing strut assembly, which caused the helicopter to tip over without warning. The accident resulted in the permanent closure of the Pan Am Building heliport.Schneider, Daniel B. [https://query.nytimes.com/gst/fullpage.html?res=9C0CE2D6143EF936A15754C0A96F958260 "F.Y.I."], 25 July 1999. Accessed 30 September 2007. "Q. Back in the 1960s and 70s, helicopters bound for Kennedy International Airport used to take off from a deck atop the old Pan Am Building. Why was the service halted? A. As many as 360 helicopter flights a day were planned by New York Airways after the 59-story Pan Am building was completed in 1963, but a bitter public outcry delayed the first few flights until December 21, 1965 ... The operation proved unprofitable since the helicopters carried an average of only eight passengers, and the heliport, which had cost $1 million to build, closed in 1968 ... After another round of hearings – and renewed protests – flights resumed in February 1977. Three months later, the landing gear on one of the Sikorsky S-61 helicopters collapsed while passengers were boarding, flipping it on its side and sending a 20-foot rotor blade skidding across the roof and over the west parapet wall ... Within hours, the heliport was closed indefinitely." As the heliport was closed, the wreckage was removed by disassembling it and taking the assemblies down to street level using the building's freight elevators. The airframe was taken to Cape Town, South Africa, where it was rebuilt, certified and returned to service for the Ship-Service Role off the shores of the Western Cape by the company "Court Helicopter" which was later amalgamated with CHC.Epstein, Curt. [http://www.ainonline.com/airshow-convention-news/hai-convention-news/single-publication-story/browse/0/article/an-s-61-with-a-past-6977/?no_cache=1&tx_ttnews%5Bstory_pointer%5D=2&tx_ttnews%5Bmode%5D=1 HAI Convention News "An S-61 With a Past"]{{dead link|date=January 2018 |bot=InternetArchiveBot |fix-attempted=yes }} 26 October 2010. Retrieved: 13 June 2011.

1980s

• On 16 July 1983, British Airways Helicopters' commercial S-61 G-BEON crashed in the southern Celtic Sea, in the Atlantic Ocean, en route from Penzance to St Mary's, Isles of Scilly, in thick fog. Only 6 of the 26 on board survived. It sparked a review of helicopter safety and was the worst civilian helicopter disaster in the UK until 1986.{{Citation needed|date=December 2008}}
• On 20 March 1985, an Okanagan Helicopters S-61N (C-GOKZ) ditched in the Atlantic Ocean off Owls Head, Nova Scotia. The aircraft was en route from the MODU Sedco 709 offshore Nova Scotia to the Halifax International Airport (YHZ) when the main gearbox suffered a total loss of transmission fluid. There were 15 passengers and 2 crew on board. There were no injuries during the ditching; however, several passengers suffered varying degrees of hypothermia. As a result of this incident, improved thermal protection and other advancements in helicopter transportation suits were instituted for offshore workers on Canada's east coast.
• On 13 July 1988, a British International Helicopters S-61N, registration G-BEID, suffered an engine failure and fire and ditched into the North Sea. There were no injuries.{{cite web |url=https://www.gov.uk/aaib-reports/3-1990-sikorsky-s61n-g-beid-13-july-1988 |title=3/1990 Sikorsky S61N, G-BEID, 13 July 1988 |publisher=AAIB (UK)}}

1990s

• On 25 July 1990, a British International Helicopters S-61, registration G-BEWL, from Sumburgh Airport crashed onto the Brent Spar oil storage platform as the pilots attempted to land. The aircraft fell into the North Sea, where 6 of the 13 passengers and crew on board died.UK Air Accidents Investigation Branch, Department of Transport, [http://www.aaib.gov.uk/cms_resources.cfm?file=/2-1991%20G-BEWL.pdf Report on the Accident to Sikorsky S-61N G-BEWL at Brent Spar, East Shetland Basin on 25 July 1990], retrieved 4 January 2014

2000s

• On 8 July 2006, a Sociedad de Salvamento y Seguridad Marítima S-61N Mk.II search and rescue helicopter, crashed into the Atlantic Ocean while flying from Tenerife to La Palma. There were no survivors among the six people on board.{{Citation needed|date=December 2010}}
• On 5 August 2008, two pilots and seven firefighters assigned to the Iron Complex fire in California's Shasta–Trinity National Forest, were killed when Carson Helicopters' S-61N N612AZ crashed on takeoff. Of the thirteen people reportedly on board, one other pilot and three firefighters survived the crash with serious or critical injuries. The NTSB determined that the probable causes were the following actions by Carson Helicopters: 1) the intentional understatement of the helicopter's empty weight, 2) the alteration of the power available chart to exaggerate lift capability, and 3) the use of unapproved above-minimum specification torque in performance calculations that, collectively, resulted in the pilots’ relying on performance calculations that significantly overestimated load-carrying capacity and without an adequate performance margin for a successful takeoff; and insufficient oversight by the U.S. Forest Service and the Federal Aviation Administration. Contributing factors were the flight crew's failure to address the fact that the helicopter had approached its maximum performance capability on two prior departures from the accident site, as they were accustomed to operating at its performance limit. Contributing to the fatalities were the immediate, intense fire due to a fuel spillage upon impact from the fuel tanks that were not crash-resistant, the separation from the floor of the cabin seats that were not crash-resistant, and the use of an inappropriate release mechanism on the seat restraints.{{cite web |url = https://www.ntsb.gov/Publictn/2010/AAR1006.htm |title = Aircraft Accident Report Crash During Takeoff of Carson Helicopters, Inc., Firefighting Helicopter Under Contract to the U.S. Forest Service, Sikorsky S-61N, N612AZ Near Weaverville, California August 5, 2008 NTSB/AAR-10/06 |website = ntsb.gov |access-date = 14 September 2017}}{{cite news |last1=La Ganga |first1=Maria L |last2=Monzino |first2=Joe |last3=Cart |first3=Julia |title=9 feared dead after helicopter plummets |url=https://www.latimes.com/archives/la-xpm-2008-aug-07-me-crash7-story.html |access-date=27 May 2025 |work=Los Angeles Times |date=7 August 2008}}{{cite news |last1=Vick |first1=Karl |title=9 Firefighters in California Helicopter Crash Are Presumed Dead |url=https://www.washingtonpost.com/archive/national/2008/08/07/9-firefighters-in-california-helicopter-crash-are-presumed-dead/dd8c4945-c5bc-4c93-b064-82669e65cae9/ |access-date=27 May 2025 |work=The Washington Post |date=7 August 2008}}

2020s

• On 22 February 2022, an S-61N being flown by Croman Corporation in support of a training operation, crashed and killed the four occupants, at the Pacific Missile Range Facility on the Hawaiian island of Kauai.[https://www.militarytimes.com/news/your-military/2022/02/22/us-military-responding-to-helicopter-crash-in-hawaii/ Four die in Hawaii crash of contractor’s helicopter, Navy says] Audrey McAvoy and Jennifer Sinco Kelleher, The Associated Press 2022-02-23

File:Sikorsky S-61L Line Drawing.svg

{{Aircraft specs

|ref= International Directiory of Civil Aircraft

|prime units?= kts

|crew= 2

|capacity = up to 30 passengers

|length ft= 58

|length in= 11

|length note=

|width ft=

|width in=

|width note=

|height ft= 17

|height in= 6

|height note=

|empty weight lb= 12,336

|empty weight note=

|gross weight lb= 16,164

|gross weight note=

|max takeoff weight lb= 19,000

|max takeoff weight note=

|fuel capacity=

|more general=

|eng1 number= 2

|eng1 name= General Electric CT58-140

|eng1 type= turboshaft engines

|eng1 shp= 1,500

|eng1 kn=

|rot number= 1

|rot dia ft= 62

|rot dia in=

|rot area sqft= 3,019

|rot area note=

• Blade section: NACA 0012{{cite web |last1 = Lednicer |first1 = David |title = The Incomplete Guide to Airfoil Usage |url = https://m-selig.ae.illinois.edu/ads/aircraft.html |website = m-selig.ae.illinois.edu |access-date = 16 April 2019}}

|max speed kts= 144

|max speed note=

|cruise speed kts= 120

|cruise speed note=

|never exceed speed kts=

|never exceed speed note=

|range nmi= 450

|range note=

|ferry range nmi=

|ferry range note=

|endurance=

|ceiling ft= 12,500

|ceiling note=

|climb rate ftmin= 1,310–2,220

|climb rate note=

|time to altitude=

|disk loading lb/sqft=

|disk loading note=

|fuel consumption lb/mi=

|power/mass=

|more performance=

|avionics=

}}

{{Portal|Aviation}}

{{Aircontent

|related=

• Sikorsky SH-3 Sea King
• Sikorsky S-62
• Sikorsky S-61R
• Sikorsky CH-124 Sea King
• Westland Sea King

|similar aircraft=

• Mil Mi-14

|lists=

|see also=

}}

{{Reflist|30em}}

• {{cite journal |last1 = Elliott |first1 = Bryn |title = On the Beat: The First 60 Years of Britain's Air Police, Part Two |journal = Air Enthusiast |date = May–June 1999 |issue = 81 |pages = 64–69 |issn = 0143-5450}}
• {{cite book |last = Frawley |first = Gerard |title = The International Directory of Civil Aircraft, 2003–2004 |page = 194 |publisher = Aerospace Publications Pty Ltd |year = 2003 |isbn = 1-875671-58-7}}
• {{cite book |last = McGowen |first = Stanley S. |title = Helicopters: An Illustrated History of Their Impact |publisher = ABC-CLIO |year = 2005 |isbn = 1-851094-68-7}}
• {{cite book |last = Sikorsky |first = Sergei I. |title = The Sikorsky Legacy |publisher = Arcadia Publishing |date = 2007 |isbn = 978-0-738549-95-8}}
• {{cite book |last = Woodley |first = Charles |title = The History of British European Airways |publisher = Casemate Publishers |year = 2006 |isbn = 1-844151-86-7}}

{{Commons category}}

• [http://www.ccg-gcc.gc.ca/helicopter/carct_sik_s61-n_e.htm Canadian Coast Guard S-61N Characteristics page]
• [http://www.flugzeuginfo.net/acdata_php/acdata_s61n_en.php S-61N Specs & Photo on flugzeuginfo.net]
• [http://www.helis.com/database/model/53/ HELIS.com Sikorsky S-61/H-3/HSS-2 Database]

{{Sikorsky Aircraft}}

{{Sikorsky S-61 family}}

{{Authority control}}

Category:1950s United States helicopters

Category:Search and rescue helicopters

Category:1950s United States civil utility aircraft

Category:Amphibious helicopters

S-061

Category:Twin-turbine helicopters

Category:Aircraft first flown in 1961

Category:Sikorsky S-61