Editing Boeing Vertol CH-46 Sea Knight (section)

==Operational history==
[[File:CH-46 Machine Gun.jpg|thumb|right|A door gunner manning a pintle-mounted .50-caliber [[M2 Browning]] machine gun aboard a Marine CH-46 in Iraq, August 2006]]

===United States===
Known colloquially as the "Phrog", the Sea Knight was used in all U.S. Marine operational environments between its introduction during the Vietnam War and its retirement in 2015.<ref name=Yuan>{{cite web|url=https://dc.medill.northwestern.edu/blog/2015/08/03/marines-say-farewell-to-the-phrog-after-its-final-flight/#sthash.0kr52ciz.dpbs|title=Marines say farewell to the Phrog after its final flight|publisher=Medill News Service|author1=Yuan Gu|author2=Siyao Long|author3=Kulwant Saluja|date=3 August 2015|access-date=20 June 2024|archive-date=20 June 2024|archive-url=https://web.archive.org/web/20240620083815/https://dc.medill.northwestern.edu/blog/2015/08/03/marines-say-farewell-to-the-phrog-after-its-final-flight/#sthash.0kr52ciz.dpbs|url-status=dead}}</ref> The type's longevity and reputation for reliability led to mantras such as "phrogs phorever" and "never trust a helicopter under 30".<ref>{{cite web|title=Ask A Marine|publisher=HMM-364 Purple Foxy Ladies|url=http://www.purplefoxyladies.com/ask.html|url-status=dead|archive-url=https://web.archive.org/web/20061230060309/http://purplefoxyladies.com/ask.html|archive-date=30 December 2006}}</ref> CH-46s transported personnel, evacuated wounded, supplied forward arming and refueling points (FARP), performed vertical replenishment, search and rescue, recovered downed aircraft and crews and other tasks.

====Vietnam War====
[[File:CH-46 Shot down during Operation Hastings.jpg|thumb|A flaming Marine CH-46 of HMM-265, after being hit by enemy AAA fire in "[[Helicopter Valley]]", 15 July 1966<ref>{{cite news |last=King |first=Tim |date=23 April 2012 |title=Vietnam's Helicopter Valley: Graveyard of Marine CH-46's |url=http://www.salem-news.com/articles/april232012/helicopter-valley-tk.php |newspaper=Salem-News.com |location=Salem, OR |access-date=12 December 2014}}</ref>]]

During the Vietnam War, the CH-46 was one of the prime US Marine troop transport helicopters in the theater, slotting between the smaller [[Bell UH-1 Iroquois]] and larger [[Sikorsky CH-53 Sea Stallion]] and progressively replacing the [[Sikorsky H-34|UH-34]]. CH-46 operations were plagued by major technical problems; the engines, being prone to [[foreign object damage]] (FOD) from debris being ingested when hovering close to the ground and subsequently suffering a [[compressor stall]], had a lifespan as low as 85 flight hours; on 21 July 1966, all CH-46s were grounded until more efficient filters had been fitted.<ref>Dunstan 2003, pp. 182–184.</ref>

On 3 May 1967, a CH-46D at [[Marine Corps Air Station Tustin|Marine Corps Air Facility Santa Ana]] crashed, killing all four members of the crew. Within three days the accident investigators had determined that the mounting brackets of the main transmission had failed, allowing the front and rear overlapping rotors to intermesh. All CH-46s were temporarily grounded for inspection. On 13 May, a CH-46A crashed off the coast of Vietnam when the tail pylon containing the engines, main transmission and aft rotors broke off in flight. All four crew members were killed. On 20 June, another CH-46A crashed, though two of the four-man crew survived. Once again, even though the aircraft was not recovered from the water, failure of some sort in the rear pylon was suspected. On 30 June a CH-46D at Santa Ana crashed when a rotor blade separated from the aircraft, all three of the crew survived. As a result of this latest accident, all CH-46Ds were immediately grounded, but the CH-46As continued flying. On 3 July another CH-46A crashed in Vietnam, killing all four Marines of its crew. The cause of the crash again was traced to failure of the main transmission.<ref name=Fails>{{citation-attribution|1={{cite book|last=Fails|first=William|title=Marines and Helicopters 1962-1973|publisher=History and Museums Division United States Marine Corps|year=1978|url=https://www.usmcu.edu/Portals/218/Marines%20and%20Helicopters%201962-1973%20%20PCN%2019000307400.pdf |archive-url=https://web.archive.org/web/20210402134726/https://www.usmcu.edu/Portals/218/Marines%20and%20Helicopters%201962-1973%20%20PCN%2019000307400.pdf |archive-date=2021-04-02 |url-status=live|isbn=978-1482313598}}}}</ref>{{rp|121–2}}

On 31 August 1967, a CH-46A on a medical evacuation mission to {{USS|Tripoli|LPH-10|6}} disintegrated in midair killing all its occupants. The following day another CH-46A experienced a similar incident at [[Marble Mountain Air Facility]] leading to the type being grounded for all except emergency situations and cutting Marine airlift capacity in half.<ref name=Telfer>{{citation-attribution|1={{cite book|last=Telfer|first=Gary I.|title=U.S. Marines in Vietnam: Fighting the North Vietnamese 1967|publisher=History and Museums Division, Headquarters, U.S. Marine Corps|year=1984|url=https://archive.org/details/FightingTheNorthVietnamese|isbn=978-1482538878}}}}</ref>{{rp|170}} An investigation conducted by a joint Naval Air Systems Command/Boeing Vertol accident investigation team revealed that structural failures were occurring in the area of the rear pylon resulting in the rear rotor tearing off in flight and may have been the cause of several earlier losses. The team recommended structural and systems modifications to reinforce the rear rotor mount as well as installation of an indicator to detect excessive strain on critical parts of the aircraft. 80 CH-46As were shipped to [[Marine Corps Air Station Futenma]], [[Okinawa Prefecture|Okinawa]] where they received the necessary modifications by a combined force of Marine and Boeing Vertol personnel. The modified CH-46As began returning to service in December 1967 and all had been returned to service by February 1968.<ref name=Telfer/>{{rp|210–1}}<ref name=Fails/>{{rp|123}}

During the 1972 [[Easter Offensive]], Sea Knights saw heavy use to convey US and [[South Vietnam]]ese ground forces to and around the front lines.<ref>Hamilton, Molly. [http://www.patriotspoint.org/news_events/former-ch-46-sea-knight-pilot-lends-expertise-to-vietnam-experience-exhibit/ "Former CH-46 Sea Knight pilot lends expertise to Vietnam Experience Exhibit."] {{Webarchive|url=https://web.archive.org/web/20150330080050/http://www.patriotspoint.org/news_events/former-ch-46-sea-knight-pilot-lends-expertise-to-vietnam-experience-exhibit/ |date=30 March 2015 }} ''patriotspoint.org'', 3 November 2014.</ref> Marine CH-46s participated in [[Operation Frequent Wind]], the evacuation of [[Saigon]], in April 1975 and the last helicopter to leave the roof of the [[Embassy of the United States, Saigon|US embassy]] was a CH-46 of [[VMM-164|HMM-164]].<ref>{{cite book |last=Dunham|first=George R|title=U.S. Marines in Vietnam: The Bitter End, 1973-1975 (Marine Corps Vietnam Operational Historical Series)|publisher=Marine Corps Association|year=1990|url=https://www.usmcu.edu/Portals/218/U_S_%20Marines%20In%20Vietnam%20-%20The%20Bitter%20End%201973%20-%201975.pdf|isbn=978016026455-9|page=200}}{{PD-notice}}</ref> By the end of US military operations in Vietnam, over a hundred Sea Knights had been lost to enemy fire.<ref name="Pensa">{{cite web |title=CH-46 Sea Knight |url=https://www.navalaviationmuseum.org/aircraft/ch-46-sea-knight/ |website=National Naval Aviation Museum |access-date=6 May 2019 |language=en |date=27 December 2008}}</ref>

====Post-Vietnam====
[[File:CH-46 HMM-261 on Grenada 1983.JPEG|thumb|left|Soldiers from the [[2nd Ranger Battalion]] board a Marine Corps CH-46E helicopter from [[VMM-261]] before the rescue of American students at St. George's University during Operation Urgent Fury in 1983.]]

In February 1968 the [[United States Marine Corps Training and Education Command|Marine Corps Development and Education Command]] obtained several CH-46s to perform herbicide dissemination tests using HIDAL (Helicopter, Insecticide Dispersal Apparatus, Liquid) systems; testing indicated the need for redesign and further study.<ref>{{cite book | last=Darrow | first=Robert A. | title=Historical, Logistical, Political and Technical Aspects of the Herbicide/Defoliant Program, 1967–1971 | publisher=Plant Sciences Laboratories, US Army Chemical Corps | location=Fort Detrick, Frederick MD | date=September 1971 | page=30}} A Resume of the Activities of the Subcommittee on Defoliation/Anticrop Systems (Vegetation Control Subcommittee) for the Joint Technical Coordinating Group/Chemical-Biological.</ref> Tandem-rotor helicopters were often used to transport nuclear warheads; the CH-46A was evaluated to deploy Naval [[Special Forces]] with the [[Special Atomic Demolition Munition]] (SADM).<ref>{{cite web |url=https://www.osti.gov/opennet/forms.jsp?formurl=films/data/0800031.html |title=0800031 Special Atomic Demolition Munition (SADM) Delivery by Parachutist/Swimmer/ Declassified U.S. Nuclear Test Film #31|website=osti.gov |publisher=Department of Energy |access-date=12 December 2014}}</ref> Nuclear Weapon Accident Exercise 1983 (NUWAX-83), simulating the crash of a Navy CH-46E carrying 3 nuclear warheads, was conducted at the [[Nevada Test Site]] on behalf of several federal agencies; the exercise, which used real radiological agents, was depicted in a [[Defense Nuclear Agency]]-produced documentary.<ref name="DTIC">{{cite book |title=NUCLEAR WEAPON ACCIDENT EXERCISE AFTER ACTION REPORT VOLUME I -EXECUTIVE QUICK LOOK |date=17 October 1983 |publisher=JOINT DEPARTMENT OF DEFENSE/DEPARTMENT OF ENERGY/FEDERAL EMERGENCY MANAGEMENT AGENCY |location=KirtlandAir Force Base, Albuquerque, New Mexico |url=https://apps.dtic.mil/dtic/tr/fulltext/u2/a136977.pdf |access-date=6 May 2019 |archive-date=6 May 2019 |archive-url=https://web.archive.org/web/20190506195928/https://apps.dtic.mil/dtic/tr/fulltext/u2/a136977.pdf |url-status=live }}</ref>

U.S. Marine CH-46s were used to deploy the [[8th Marine Regiment]] into [[Grenada]] during [[Operation Urgent Fury]], evacuated the surviving crewmember of a downed AH-1 Cobra, and then carried infantry from the [[75th Ranger Regiment]] to secure and evacuate U.S. students at [[St. George's University]], though one crashed after colliding with a palm tree.

[[File:US Navy 040506-M-7034A-040 Lance Cpl. Mike Carro holds security for the Marines assigned to Battalion Landing Team 1-6, after disembarking a Marine CH-46 Sea Knight helicopter during the initial surge of the 22nd Marine Expedit.jpg|thumb|A CH-46 departing after dropping off Marines of the [[22nd Marine Expeditionary Unit]] in South Central Afghanistan, 2004]]
CH-46E Sea Knights were also used by the U.S. Marine Corps during the [[2003 invasion of Iraq]]. In one incident on 1 April 2003, Marine CH-46Es and CH-53Es carried U.S. Army Rangers and Special Operations troops on an extraction mission for captured Army Private [[Jessica Lynch]] from an Iraqi hospital.<ref>Stout, Jay A. ''Hammer from Above, Marine Air Combat Over Iraq''. Ballantine Books, 2005. {{ISBN|978-0-89141-871-9}}.</ref> During the subsequent occupation of Iraq and counter-insurgency operations, the CH-46E was heavily used in the CASEVAC role, being required to maintain 24/7 availability regardless of conditions.<ref>Cheeca, Rocky. [http://www.airspacemag.com/military-aviation/evacuating-the-injured-43013675/?no-ist "Evacuating the Injured."] ''Air & Space Magazine'', September 2012.</ref> According to authors Williamson Murray and Robert H Scales, the Sea Knight displayed serious reliability and maintenance problems during its deployment to Iraq, as well as "limited lift capabilities".<ref>Murray and Scales 2005, p. 272.</ref> Following the loss of numerous US helicopters in the Iraqi theatre, the Marines opted to equip their CH-46s with more advanced anti-missile countermeasures.<ref name="Warwick">{{cite web |last1=Warwick |first1=Graham |title=Picture: US Marine Corps tests anti-missile system for Boeing CH-46 Sea Knight as Iraq helicopter shoot-downs mount |url=https://www.flightglobal.com/news/articles/picture-us-marine-corps-tests-anti-missile-system-for-boeing-ch-46-sea-knight-as-iraq-helicopter-212283/ |website=Flightglobal.com |access-date=6 May 2019 |date=23 February 2007}}</ref>

The U.S. Navy retired the type on 24 September 2004, replacing it with the [[SH-60 Seahawk|MH-60S Seahawk]];<ref name="Navy Swan song">{{cite web |last = Crawley|first=James W.|title=Swan song for Navy's ugly-duckling copter |publisher=SignonSanDiego.com |url=http://www.signonsandiego.com/uniontrib/20040924/news_2m24phrog.html}}</ref> the Marine Corps maintained its fleet as the [[V-22 Osprey|MV-22 Osprey]] was fielded.<ref>{{cite journal|year=2006|title=Major Acquisition Programs – Aviation Combat Element Programs|url=http://hqinet001.hqmc.usmc.mil/p&r/concepts/2006/PDF/Chapter%203/Part%203/C&P2006Chap3Part3AviationCombatElementPg188-190MV-22%20Osprey.pdf|publisher=Headquarters Marine Corps|url-status=dead|archive-url=https://web.archive.org/web/20070614214327/http://hqinet001.hqmc.usmc.mil/p%26r/concepts/2006/PDF/Chapter%203/Part%203/C%26P2006Chap3Part3AviationCombatElementPg188-190MV-22%20Osprey.pdf|archive-date=14 June 2007}}</ref> In March 2006 Marine Medium Helicopter Squadron 263 (HMM-263) was deactivated and redesignated [[VMM-263]] to serve as the first MV-22 squadron.<ref>{{cite web |last=White |first=LCpl Samuel |title=VMM-263 ready to write next chapter in Osprey program |publisher=U.S. Marine Corps |url=http://www.marines.mil/marinelink/mcn2000.nsf/0/217128503734FF2B8525712A004D67BC?opendocument |url-status=dead |archive-url=https://web.archive.org/web/20080201011556/http://www.marines.mil/marinelink/mcn2000.nsf |archive-date=1 February 2008}}</ref> The replacement process continued through the other medium helicopter squadrons into 2014. On 5 October 2014, the Sea Knight performed its final service flight with the U.S. Marine Corps at [[Marine Corps Air Station Miramar]]. [[HMM-364]] was the last squadron to use it outside the United States, landing it aboard {{USS|America|LHA-6|6}} on her maiden transit. On 9 April 2015, the CH-46 was retired by the [[Marine Medium Helicopter Training Squadron 164]], the last Marine Corps squadron to transition to the MV-22.<ref name="Military.com">{{cite web |title=Venerable 'Sea Knight' Makes Goodbye Flights |url=http://www.military.com/daily-news/2014/10/03/venerable-sea-knight-makes-goodbye-flights.html |website=military.com |access-date=6 May 2019 |date=3 October 2014}}</ref><ref>[http://news.usni.org/2015/04/10/marines-bid-phrog-farewell-to-last-active-ch-46e-sea-knight-squadron Marines Bid ‘Phrog’ Farewell to Last Active CH-46E Sea Knight Squadron] – News.USNI.org, 10 April 2015</ref> The USMC retired the CH-46 on 1 August 2015 in a ceremony at the [[Steven F. Udvar-Hazy Center|Udvar-Hazy Center]] near Washington DC.<ref name=Yuan/>

Beginning in April 2011 the Navy's [[Fleet Readiness Center East]] began refurbishing retired USMC CH-46Es for service with the [[United States Department of State Air Wing]].<ref>{{cite web|url=https://www.navair.navy.mil/node/18731|title=Sea Knight gets new life|publisher=Naval Air Systems Command|date=9 March 2012|accessdate=16 August 2021|archive-date=16 August 2021|archive-url=https://web.archive.org/web/20210816053941/https://www.navair.navy.mil/node/18731|url-status=dead}}</ref> A number of CH-46s from [[HMX-1]] were transferred to the Air Wing in late 2014.<ref>{{cite web|url=https://www.marines.mil/News/News-Display/Article/497063/half-a-century-spent-making-phrogs-fly/|title=Half a century making Phrogs fly|publisher=United States Marine Corps|author=Sgt. Melissa Karnath|date=10 September 2014|accessdate=16 August 2021}}</ref> In Afghanistan the CH-46s were used by Embassy Air for secure transport of State Department personnel. The CH-46s were equipped with missile warning sensors and flare dispensers and could be armed with M240D or M2 Browning machine guns.<ref>{{cite web|url=https://theaviationist.com/2020/03/24/interesting-new-photos-of-armed-embassy-air-ch-46e-helicopter-at-u-s-embassy-in-kabul-emerge/|title=Interesting New Photos Of Armed "Embassy Air" CH-46E Helicopter At U.S. Embassy in Kabul Emerge|author=David Cenciotti|publisher=The Aviationist|date=24 March 2020|accessdate=16 August 2021}}</ref> A report in September 2019 by the [[Department of State Office of Inspector General|State Department Inspector General]] found that a seat on a CH-46 for a seven-minute flight cost US$1,500 (~${{Format price|{{Inflation|index=US-GDP|value=1500|start_year=2019}}}} in {{Inflation/year|US-GDP}}).<ref>{{cite news |newspaper=Stars and Stripes |title=Report: Expensive airfares harm embassy operations in Afghanistan and Iraq |author=Philip Wellman |date=24 September 2019 |url=https://www.stripes.com/theaters/middle_east/report-expensive-airfares-harm-embassy-operations-in-afghanistan-and-iraq-1.600300}}</ref>

====Evacuation of Afghanistan====
[[File:State Department Air Wing CH-46E.jpg|thumb|[[State Department Air Wing]] CH-46E, 2012]]

Seven of the State Department Air Wing CH-46s took part in the [[2021 Kabul Airlift]]. Prior to the complete withdrawal of U.S. forces, all seven were rendered unusable and abandoned at [[Kabul International Airport]] and are seen in many videos and pictures online. One of the CH-46s that was abandoned (BuNo 154038, c/n 2389) also took part in [[Operation Frequent Wind]] 46 years earlier. The U.S. State Department drew criticism for leaving behind the aircraft. Commenting on the issue, the U.S. State Department claimed that the helicopters were already being phased out of State Department Air Wing due to their age and the inability to support them. The seven CH-46s left behind were the only U.S. State Department aircraft left behind at Kabul International Airport.<ref>{{cite news |url=https://www.bbc.com/news/world-58393763 |title=Afghanistan: What was left behind by US forces? |publisher=BBC News |date=31 August 2021 |accessdate=1 September 2021}}</ref>

===Canada===
[[File:Labrador helicopter landing Bell Island.jpg|thumb|left|CH-113 Labrador landing on "The Clapper", a [[sea stack]] off the tip of [[Bell Island (Newfoundland and Labrador)|Bell Island]] in Newfoundland]]

The [[Royal Canadian Air Force]] procured six CH-113 Labrador helicopters for the SAR role and the [[Canadian Army]] acquired 12 of the similar CH-113A Voyageur for the medium-lift transport role. The RCAF Labradors were delivered first with the first one entering service on 11 October 1963.<ref name="Milberry">Milberry, Larry: ''Sixty Years – The RCAF and Air Command 1924–1984'', p. 472. McGraw Hill Ryerson, 1984. {{ISBN|0-07-549484-1}}</ref><ref name=CAM>{{cite web|title=Boeing Vertol CH-113 Labrador|url=http://casmuseum.techno-science.ca/en/collection-research/artifact-boeing-vertol-ch-113-labrador.php|website=Canada Aviation and Space Museum|publisher=Canada Science and Technology Museums Corporation|access-date=10 July 2015}}</ref> When the larger CH-147 Chinook was procured by the [[Canadian Forces]] in the mid-1970s, the Voyageur fleet was converted to Labrador specifications to undertake SAR missions. The refurbished Voyageurs were re-designated as CH-113A Labradors, thus a total of 15 Labradors were ultimately in service.<ref name="CAM" />

The Labrador was fitted with a watertight hull for marine landings, a 5,000 kilogram cargo hook and an external rescue hoist mounted over the right front door. It featured a 1,110 kilometer flying range, emergency medical equipment and an 18-person passenger capacity.<ref name="CAM" /> In multiple instances throughout the 1970s and 1980s, this increased range provided the capability of the CH-113 to provide assistance to [[U.S. Coast Guard]] (USCG) missions or perform long range medevacs over distances the USCG helicopters at the time simply could not reach.<ref>{{cite web | title=Top Ten Coast Guard Rescues |date=Jul 31, 2007 |author=<!--Not stated--> |url=https://coastguardnews.com/top-ten-coast-guard-rescues/2007/07/31/ |publisher=Coast Guard News |accessdate=19 December 2019 }}</ref>

In 1981, a mid-life upgrade of the fleet was carried out by [[Boeing Canada]] in [[Arnprior, Ontario]]. Known as the SAR-CUP (Search and Rescue Capability Upgrade Program), the refit scheme included new instrumentation, a nose-mounted weather radar, a tail-mounted auxiliary power unit, a new high-speed rescue hoist mounted over the side door and front-mounted searchlights. A total of six CH-113s and five CH-113As were upgraded with the last delivered in 1984. Nonetheless, as a search and rescue helicopter it endured heavy use and hostile weather conditions; which had begun to take their toll on the Labrador fleet by the 1990s, resulting in increasing maintenance costs and the need for prompt replacement.<ref name="CAM" />

In 1992, it was announced that the Labradors were to be replaced by 15 new helicopters, a variant of the [[AgustaWestland EH101]], designated ''CH-149 Chimo''. The order was subsequently cancelled by the [[Jean Chrétien]] [[Liberal Party of Canada|Liberal]] government in 1993, resulting in cancellation penalties, as well as extending the service life of the Labrador fleet. However, in 1998, a CH-113 from [[CFB Greenwood]] crashed on Quebec's [[Gaspé Peninsula]] while returning from a SAR mission, resulting in the deaths of all crewmembers on board. The crash placed pressure upon the government to procure a replacement, thus an order was placed with the manufacturers of the EH101 for 15 aircraft to perform the search-and-rescue mission, designated ''[[CH-149 Cormorant]]''. CH-149 deliveries began in 2003, allowing the last CH-113 to be retired in 2004.<ref name="CAM" /> In October 2005 [[Columbia Helicopters]] of [[Aurora, Oregon]] purchased eight of the retired CH-113 Labradors to add to their fleet of 15 Vertol 107-II helicopters.<ref>{{cite web|url=http://www.shephard.co.uk/Rotorhub/default.aspx?Action=745115149&ID=c186be12-8152-418b-9b56-ec198753da2e|title=Columbia Helicopters Acquires eight CH-113 Labrador helicopters from Canadian military|publisher=RotorHub.com|work=RotorHub|archive-url=https://web.archive.org/web/20071222234834/http://www.shephard.co.uk/Rotorhub/default.aspx?Action=745115149&ID=c186be12-8152-418b-9b56-ec198753da2e |archive-date=22 December 2007|access-date=5 December 2010}}</ref>

=== Sweden ===
[[File:Boeing Vertol Hkp4A (107-II-4), Sweden - Air Force AN1113714.jpg|thumb|A HKP 4A variant with the [[Swedish Air Force]]]]

In 1963, Sweden procured ten UH-46Bs from the US as a transport and anti-submarine helicopter for the [[Swedish Armed Forces]], designated Hkp 4A. In 1973, a further eight Kawasaki-built KV-107s, which were accordingly designated Hkp 4B, were acquired to replace the older Piasecki H-21. During the Cold War, the fleet's primary missions were anti-submarine warfare and troop transportation. They were also frequently employed in the search and rescue role, most famously during the rescue operation of the [[MS Estonia|MS ''Estonia'']] after it [[Sinking of the MS Estonia|sank in the Baltic Sea]] on 28 September 1994. In the 1980s, the Hkp 4A was phased out, having been replaced by the [[Eurocopter AS332 Super Puma]]; the later Kawasaki-built Sea Knights continued in operational service until 2011, they were replaced by the [[UH-60 Black Hawk]] and [[NH90]].

===Argentina===
On 15 September 2023, [[Argentina]]'s [[Argentine Air Force|Air Force]] chief Gen. [[Xavier Issac]] briefed the media that Argentina had sent a letter requesting the US to approve the refurbishment of surplus CH-46s currently stored with the [[309th Aerospace Maintenance and Regeneration Group]] in [[Arizona]]. The availability of civilian-operated CH-46s was also being explored. They would be used to support [[Argentine Antarctica#Argentine bases|Argentina's Antarctic bases]]. The CH-46s would replace two [[Mil Mi-17#Export variants|Mil Mi-171E]] helicopters acquired in 2010, but now not able to be repaired by [[Russia]] due to sanctions from the [[Russian invasion of Ukraine]].<ref name="2023-09-22_DN">Higuera, José. [https://www.defensenews.com/global/the-americas/2023/09/21/argentina-eyes-surplus-ch-46-helicopters-as-mi-17-replacement/ "Argentina eyes surplus CH-46 helicopters as Mi-17 replacement"]. Defense News, 23 September 2023.</ref>

===Civilian and others===
[[File:P2CHE.jpg|thumb|Columbia Helicopters BV 107-II in Papua New Guinea]]

The civilian version, designated as the BV 107-II ''Vertol'',<ref name="vert_Columbia">Eichel, Garth. "Columbia Helicopters". ''Vertical Magazine'', February–March 2007.</ref> was developed prior to the military CH-46. It was operated commercially by New York Airways, [[Pan American World Airways]] and later on by Columbia Helicopters.<ref name="vert_Columbia"/> Among the diversity of tasks was commuter service in the mid-1960s from the roof of the [[MetLife Building|Pan Am skyscraper]] in Manhattan to [[John F. Kennedy International Airport|JFK Airport]] in Queens,<ref name="Schneider">{{Cite news |last=Schneider |first=Daniel B. |date=July 25, 1999 |title=F.Y.I. |language=en-US |work=The New York Times |url=https://www.nytimes.com/1999/07/25/nyregion/fyi-729590.html |access-date=March 25, 2021 |issn=0362-4331 |archive-date=August 12, 2019 |archive-url=https://web.archive.org/web/20190812100032/https://www.nytimes.com/1999/07/25/nyregion/fyi-729590.html |url-status=live}}</ref> pulling a [[hover barge]],<ref>[http://verticalmag.com/news/articles/happy-birthday-to-columbia-helicopters--oregon-based-company-celebrates-its-50th-anniversary.html "Happy birthday to Columbia Helicopters! Oregon-based company celebrates its 50th anniversary"] ''Vertical (magazine)'', 18 April 2007. Retrieved: 24 August 2012.</ref><ref>[http://www.colheli.com/news/the_hover_barge/ "The hover barge"] {{webarchive|url=https://web.archive.org/web/20160213052802/http://www.colheli.com/news/the_hover_barge/ |date=13 February 2016}} ''[[Columbia Helicopters]]''. Retrieved: 24 August 2012.</ref> and constructing [[transmission tower]]s for [[overhead power line]]s.<ref>{{cite web|url=http://www.verticalmag.com/news/article/PoweringUp |archive-url=https://web.archive.org/web/20151004113042/http://www.verticalmag.com/news/article/PoweringUp |title=Powering Up – Vertical Magazine |archive-date=4 October 2015 |work=verticalmag.com |access-date=4 October 2015 |url-status=live}}</ref>

In December 2006, Columbia Helicopters purchased the type certificate of the Model 107 from Boeing, with the aim of eventually producing new-build aircraft themselves.<ref>{{cite web |title=Type Certificate Data Sheet No. 1H16 |publisher=Federal Aviation Administration |date=17 January 2007 |url=http://www.airweb.faa.gov/Regulatory_and_Guidance_Library%5CrgMakeModel.nsf/0/FA4E77BC4812A0258625726B00663586/$FILE/1H16.pdf |access-date=8 February 2007 |archive-url=https://web.archive.org/web/20200219070151/https://www.airweb.faa.gov/Regulatory_and_Guidance_Library%5CrgMakeModel.nsf/0/FA4E77BC4812A0258625726B00663586/$FILE/1H16.pdf |archive-date=19 February 2020 |url-status=dead}}</ref> In 2023, Columbia Helicopters began a program of purchasing older Model 107-II and CH-46E airframes, and refurbishing them into Model 107-IIs for sale.<ref name="Columbia South Korea">{{cite web |title=Columbia Helicopters sells Columbia Model 107-II to Daejin Air in South Korea |url=https://verticalmag.com/press-releases/columbia-helicopters-sells-columbia-model-107-ii-to-daejin-air-in-south-korea/ |website=VerticalMag |publisher=Vertical Mag |access-date=21 January 2025}}</ref><ref name="Columbia buys new helicopters">{{cite web |title=Columbia Helicopters buys ten Vertol 107s from Swedish military |url=https://www.helihub.com/2013/02/27/columbia-helicopters-buys-ten-vertol-107s-from-swedish-military/ |website=HeliHub |date=27 February 2013 |access-date=21 January 2025}}</ref> Columbia Helicopters has also updated old airframes into the ''Model 107-III''.<ref name="107-III" />