Editing Boeing Vertol CH-46 Sea Knight (section)

====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>