Editing Boeing CH-47 Chinook (section)

==Design and development==
[[File:NARA 111-CCV-105-CC65957 CH-47 lifting off from Fire Support Base Challenge with 105 mm howitzer April 1970.jpg|thumb|CH-47 carries a howitzer, 1970.]]

===Initial development===
During late 1956, the United States Department of the Army announced its intention to replace the [[Sikorsky CH-37 Mojave]], which was powered by [[Radial engine|piston engines]], with a new, [[Gas turbine|gas turbine-powered]] helicopter.<ref name="Tolsonarmy">{{cite book |url=https://www.history.army.mil/html/books/090/90-4/index.html |title= Vietnam Studies: Airmobility 1961–71 |department= Department of the Army |author= Lt General John J. Tolson |year= 1989 |publisher= US Government Printing Office |id= CMH Pub 90-4 |access-date= 19 August 2010 |archive-url= https://web.archive.org/web/20100612073527/http://www.history.army.mil/books/Vietnam/Airmobility/airmobility-fm.html |archive-date= 12 June 2010 |url-status= dead}}</ref> Turbine engines were also a key design feature of the smaller [[Bell UH-1 Iroquois|UH-1 "Huey"]] utility helicopter. Following a design competition, in September 1958, a joint Army–Air Force source selection board recommended that the Army procure the [[Piasecki Helicopter|Vertol]]-built medium transport helicopter. However, funding for full-scale development was not then available, and the Army vacillated on its design requirements. Some officials in [[United States Army Aviation Branch|Army Aviation]] thought that the new helicopter should be operated as a light tactical transport aimed at taking over the missions of the old piston-engined [[Piasecki H-21]] and [[Sikorsky H-34]] helicopters, and be consequently capable of carrying about 15 troops (one [[squad]]). Another faction in Army Aviation thought that the new helicopter should be much larger, enabling it to [[airlift]] large [[artillery]] pieces and possess enough internal space to carry the new [[MGM-31 Pershing|MGM-31 "Pershing" missile system]].<ref name="Tolsonarmy"/>

[[File:HC-1B in flight being tested and evaluated.jpg|thumb|left|HC-1B during in-flight evaluation]]
During 1957, Vertol commenced work upon a new tandem-rotor helicopter, designated as the Vertol Model 107 or V-107.<ref name=Apostolo>Apostolo, Giorgio. ''The Illustrated Encyclopedia of Helicopters''. New York: Bonanza Books. 1984. {{ISBN|978-0-517-43935-7}}.</ref><ref name=vect_V-107>Goebel, Greg. {{usurped|1=[https://web.archive.org/web/20120623191825/http://www.vectorsite.net/avch47.html#m1 Origins: Vertol V-107 & V-114]}}. Vectorsite.net, 1 December 2009.</ref> During June 1958, the U.S. Army awarded a contract to Vertol for the acquisition of a small number of the rotorcraft, giving it the ''YHC-1A'' designation.<ref name="whirly">Spenser, Jay P. ''Whirlybirds, A History of the U.S. Helicopter Pioneers''. University of Washington Press, 1998. {{ISBN|0-295-97699-3}}.</ref> As ordered, the YHC-1A possessed the capacity to carry a maximum of 20 troops.<ref name="Tolsonarmy"/> Three underwent testing by the Army for deriving engineering and operational data. However, the YHC-1A was considered by many figures within the Army users to be too heavy for the assault role, while too light for the more general transport role.<ref name="Tolsonarmy"/> Accordingly, a decision was made to procure a heavier transport helicopter, and at the same time, upgrade the UH-1 "Huey" to serve as the needed tactical troop transport. The YHC-1A would be improved and adopted by the Marines as the [[Boeing Vertol CH-46 Sea Knight|CH-46 Sea Knight]] in 1962.<ref>{{cite news |url= https://pqasb.pqarchiver.com/latimes/access/454317782.html?dids=454317782:454317782&FMT=ABS&FMTS=ABS:AI&type=historic&date=Oct+26%2C+1962&author=&pub=Los+Angeles+Times&desc=The+Quiet+Americans--Our+Marines+Overseas&pqatl=google |title= The Quiet Americans-Our Marines Overseas |first= Alexander |last= Holmes |work= Los Angeles Times |date= 26 October 1962 |access-date= 5 July 2017 |archive-url= https://web.archive.org/web/20121026080022/http://pqasb.pqarchiver.com/latimes/access/454317782.html?dids=454317782:454317782&FMT=ABS&FMTS=ABS:AI&type=historic&date=Oct+26,+1962&author=&pub=Los+Angeles+Times&desc=The+Quiet+Americans--Our+Marines+Overseas&pqatl=google |archive-date= 26 October 2012 |url-status= dead}}</ref> As a result, the Army issued a new order to Vertol for an enlarged derivative of the V-107, known by internal company designation as the Model 114, which it gave the designation of HC-1B.<ref>{{cite web |url= http://www.flightglobal.com/articles/2008/04/01/222553/chinook-five-decades-of-development.html |title= Chinook: Five decades of development |first= Graham |last= Warwick |work= Flight International |date= 1 April 2008 |access-date= 29 March 2010 |archive-url= https://web.archive.org/web/20081011030804/http://www.flightglobal.com/articles/2008/04/01/222553/chinook-five-decades-of-development.html |archive-date= 11 October 2008 |url-status= live}}</ref> On 21 September 1961, the preproduction [[Boeing Vertol]] YCH-1B made its initial hovering flight. During 1962, the HC-1B was redesignated the CH-47A under the [[1962 United States Tri-Service aircraft designation system]]; it was also named "Chinook" after the Chinook people of the Pacific Northwest.<ref>{{cite web|url=https://www.defense.gov/News/Inside-DOD/Blog/Article/2052989/why-army-helicopters-have-native-american-names/|archive-url=https://web.archive.org/web/20210923214323/https://www.defense.gov/News/Inside-DOD/Blog/Article/2052989/why-army-helicopters-have-native-american-names/|url-status=dead|archive-date=23 September 2021|title=Why Army Helicopters Have Native American Names|first=Katie|last=Lange|date=2019-11-29|access-date=2021-12-20|publisher=Department of Defense}}</ref>

{{Listen
| filename= Chinook helicopter flying over Greenwich in London.ogg
| title= Chinook helicopter flying overhead in Greenwich, London
| description= The distinctive sound of the Chinook helicopter, recorded May 2016.
}}
The CH-47 is powered by two [[turboshaft]] engines, mounted on each side of the helicopter's rear pylon and connected to the rotors by drive shafts. Initial models were fitted with [[Lycoming T55]] engines rated at {{convert|2200|hp|kW|abbr=on}} each. The counter-rotating rotors eliminate the need for an antitorque vertical rotor, allowing all power to be used for lift and thrust. The ability to adjust lift in either rotor makes it less sensitive to changes in the center of gravity, important for the cargo lifting and dropping. While hovering over a specific location, a twin-rotor helicopter has increased stability over a single rotor when weight is added or removed, for example, when troops drop from or begin climbing up ropes to the aircraft, or when other cargo is dropped. If one engine fails, the other can drive both rotors.<ref>{{cite web|url=http://www.chinook-helicopter.com/standards/areas/drive_train.html|title=Chinook Information and diagrams about the transmission system|access-date=13 November 2014|archive-url=https://web.archive.org/web/20150330094029/http://www.chinook-helicopter.com/standards/areas/drive_train.html|archive-date=30 March 2015|url-status=dead}}</ref> The "sizing" of the Chinook was directly related to the growth of the Huey and the Army's tacticians' insistence that initial air assaults be built around the squad. The Army pushed for both the Huey and the Chinook, and this focus was responsible for the acceleration of its air mobility effort.<ref name="Tolsonarmy"/>

===Improved and later versions===
[[File:JG-2923 rear door ramp.jpg|thumb|left|A Chinook with its rear ramp lowered]]

Improved and more powerful versions of the CH-47 have been developed since the helicopter entered service. Often the same airframe was upgraded to later standards, or sometimes the airframes were built to the newer upgrade. The U.S. Army's first major design leap was the now-common CH-47D, which entered service in 1982. Improvements from the CH-47C included upgraded engines, composite rotor blades, a redesigned cockpit to reduce pilot workload, improved and redundant electrical systems, an advanced flight control system, and improved avionics.<ref>{{cite news |url= http://nl.newsbank.com/nl-search/we/Archives?p_product=PI&s_site=philly&p_multi=PI&p_theme=realcities&p_action=search&p_maxdocs=200&p_topdoc=1&p_text_direct-0=0EB293DCB78A3557&p_field_direct-0=document_id&p_perpage=10&p_sort=YMD_date:D&s_trackval=GooglePM |title= This Whirlybird's an early bird: Boeing Vertol's Army copter delivered on budget |first= Tom |last= Belden |website= The Philadelphia Inquirer |date= 21 May 1982 |access-date= 5 April 2010 |archive-url= https://web.archive.org/web/20110608230930/http://nl.newsbank.com/nl-search/we/Archives?p_product=PI&s_site=philly&p_multi=PI&p_theme=realcities&p_action=search&p_maxdocs=200&p_topdoc=1&p_text_direct-0=0EB293DCB78A3557&p_field_direct-0=document_id&p_perpage=10&p_sort=YMD_date:D&s_trackval=GooglePM |archive-date= 8 June 2011 |url-status= live}}</ref> The latest (2009) mainstream generation is the CH-47F, which features several major upgrades to reduce maintenance, digitized flight controls, and is powered by two {{convert|4733|hp|kW|adj=on}} Honeywell engines.<ref name="boeing">{{cite web |url= http://boeing.mediaroom.com/index.php?s=43&item=784 |title= Boeing Receives $1.15B Contract for 15 Canadian Chinooks, Announces Matching Reinvestment in Industry |publisher= Boeing |date= 10 August 2009 |access-date= 11 August 2009 |archive-url= https://web.archive.org/web/20110725093825/http://boeing.mediaroom.com/index.php?s=43&item=784 |archive-date= 25 July 2011 |url-status= live}}</ref>

[[File:CH-47_Cockpit.jpg|thumb|CH-47 cockpit view, 2022]]
An example of a British upgraded version is the HC.4; the first HC.4 first flew on 9 December 2010.<ref>Parsons, Gary. [http://www.key.aero/view_news.asp?ID=2915&thisSection=military "First Project Julius Chinook flies"] {{webarchive |url=https://web.archive.org/web/20120314151556/http://www.key.aero/view_news.asp?ID=2915&thisSection=military |date=14 March 2012 }}. Key Publishing via key.aero, 24 January 2011.</ref>
A commercial model of the Chinook, the Boeing-Vertol Model 234, is used worldwide for logging, construction, fighting forest fires, and supporting petroleum extraction operations. In December 2006, [[Columbia Helicopters]] Inc purchased the [[type certificate]] of the Model 234 from Boeing.<ref>{{cite web |title= Type Certificate Data Sheet No. H9EA |publisher= Federal Aviation Administration |date= 17 January 2007 |url= http://www.airweb.faa.gov/Regulatory_and_Guidance_Library%5CrgMakeModel.nsf/0/84EBE8780BF584058625726B00657D0E/$FILE/H9EA.pdf |archive-url= https://wayback.archive-it.org/all/20070614191643/http://www.airweb.faa.gov/Regulatory_and_Guidance_Library%5CrgMakeModel.nsf/0/84EBE8780BF584058625726B00657D0E/$FILE/H9EA.pdf |url-status= dead |archive-date= 14 June 2007 |format= .pdf |access-date= 8 February 2007}}</ref> The Chinook has also been licensed to be built by companies outside the United States, such as [[Agusta]] (now [[AgustaWestland]]) in Italy and [[Kawasaki Heavy Industries|Kawasaki]] in Japan.<ref>{{cite press release |date=2013-06-26 |title=AW1067 ICH-47F Maiden Flight |url=https://www.leonardocompany.com/en/press-release-detail/-/detail/aw1067i-ch-47-f-maiden-flight |location=Vergiate |publisher=Leonardo |access-date=2021-12-20}}</ref><ref>{{cite web|title=CH-47JA Helicopter|access-date=2021-12-20|publisher=Kawasaki|url=https://global.kawasaki.com/en/mobility/air/helicopters/ch_47j.html}}</ref>

===CH-47F orders===
In February 2007, the [[Royal Netherlands Air Force]] became the first international customer of the CH-47F model, expanding their Chinook fleet to seventeen.<ref name=boeing-pr-sign>{{cite press release |url=http://www.boeing.com/news/releases/2007/q1/070215b_nr.html |publisher=Boeing |title=Boeing Signs Contract for Dutch Chinooks |access-date=1 April 2015 |date=15 February 2007 |url-status=dead |archive-url=https://web.archive.org/web/20130621160310/http://www.boeing.com/news/releases/2007/q1/070215b_nr.html |archive-date=21 June 2013}}</ref> On 10 August 2009, Canada signed a contract for fifteen extensively modified and upgraded CH-47Fs for the [[Canadian Armed Forces|Canadian Forces]], later delivered in 2013–2014 with the Canadian designation CH-147F.<ref name=boeing /><ref name=globe-mail-late>{{cite web |last1=Leblanc |first1=Daniel |url=https://www.theglobeandmail.com/news/politics/forces-ink-deal-for-new-copters/article1247229/ |title=Chinooks will fly too late for Afghanistan |work=The Globe and Mail |access-date=1 April 2015 |date=10 August 2009 |url-status=dead |archive-url=https://web.archive.org/web/20090814212331/http://www.theglobeandmail.com/news/politics/forces-ink-deal-for-new-copters/article1247229/ |archive-date=14 August 2009}}</ref> On 15 December 2009, Britain announced its Future Helicopter Strategy, including the purchase of twenty-four new CH-47Fs to be delivered from 2012.<ref>[http://www.defensenews.com/story.php?i=4420094&c=EUR&s=AIR "As Cuts Loom, Britain Orders 24 Chinooks From Boeing"]. Defense News, 15 December 2009.{{dead link |date=April 2015}}</ref> Australia ordered seven CH-47Fs in March 2010 to replace its six CH-47Ds between 2014 and 2017.<ref>[http://www.defenseindustrydaily.com/Australia-Ordering-CH-47F-Chinooks-05395/ "Australia Ordering CH-47F Chinooks"] {{Webarchive |url=https://web.archive.org/web/20111103142901/http://www.defenseindustrydaily.com/Australia-Ordering-CH-47F-Chinooks-05395/ |date=3 November 2011}}. Defense Industry Daily, 22 March 2010.</ref><ref>{{cite web |url=http://www.minister.defence.gov.au/gregCombettpl.cfm?CurrentId=10063 |title=New Chinook CH-47 helicopters |last=The Hon. Greg Combet AM MP |date=20 March 2010 |work=Media Release |publisher=Australian Department of Defence |url-status=dead |archive-url=https://web.archive.org/web/20100324214913/http://www.minister.defence.gov.au/gregCombettpl.cfm?CurrentId=10063 |archive-date=24 March 2010}}</ref> In September 2015, [[India]] approved purchase of fifteen CH-47F Chinooks.<ref>{{cite web |url= http://indiatoday.intoday.in/story/india-clears-purchase-of-15-chinooks-and-22-apache-helicopters-from-us/1/480655.html |title= India clears purchase of 15 Chinooks and 22 Apache helicopters from US |work= intoday.in |date= 23 September 2015 |access-date= 27 September 2015 |archive-url= https://web.archive.org/web/20150928031425/http://indiatoday.intoday.in/story/india-clears-purchase-of-15-chinooks-and-22-apache-helicopters-from-us/1/480655.html |archive-date= 28 September 2015 |url-status= live}}</ref> On 7 November 2016, Singapore announced that the CH-47F would replace its older Chinooks, which had been in service since 1994, enabling the [[Republic of Singapore Air Force]] to meet its requirements for various operations, including Search and Rescue (SAR), Aeromedical Evacuation (AME), and Humanitarian Assistance and Disaster Relief (HADR) operations.<ref>{{cite web |url=https://www.mindef.gov.sg/imindef/press_room/details.html?name=07nov16_nr2&date=2016-11-07 |title=MINDEF Signs Contracts to Acquire New Medium- and Heavy-Lift Helicopters |last=Government of Singapore |date=7 November 2016 |archive-url=https://web.archive.org/web/20161107221721/https://www.mindef.gov.sg/imindef/press_room/details.html?name=07nov16_nr2&date=2016-11-07 |archive-date=7 November 2016 |url-status=dead |access-date=7 November 2016}}</ref> The German government announced in June 2022 that the CH-47F Block 2 was selected as the winner of its heavy helicopter program to replace its [[Sikorsky CH-53K#Failed bids|Sikorsky CH-53G]] Sea Stallion fleet.<!-- The C-47F is to be delivered to the Bundeswehr (German Armed Forces) between 2023 and 2029. (The text in source indicates these are "plans", not a contracted terms.) --><ref>{{cite web |url= https://www.aviacionline.com/2022/06/breaking-germany-makes-its-choice-for-boeings-ch-47-chinook-official/ |title= Breaking: Germany makes its choice for Boeing's CH-47 Chinook official |website= aviacionline.com |date= 1 June 2022 |access-date= 19 June 2022}}</ref><ref name=":0">{{Cite web |title=Germany – CH-47F Chinook Helicopters {{!}} Defense Security Cooperation Agency |url=https://www.dsca.mil/press-media/major-arms-sales/germany-ch-47f-chinook-helicopters |access-date=2023-05-13 |website=www.dsca.mil}}</ref> Germany is planning to buy sixty airframes to boost heavy lift capability.<ref>{{Cite web |date=2023-05-11 |title=US approves $8.5 billion sale of Chinook helicopters to Germany |url=https://www.seattletimes.com/nation-world/nation/us-approves-8-5-billion-sale-of-chinook-helicopters-to-germany/ |access-date=2024-04-06 |website=The Seattle Times |language=en-US}}</ref>

Spain had seventeen CH-47s which it is planning to upgrade CH-47F standard.<ref>{{cite web |last1=Waldron |first1=Greg |title=Boeing to upgrade Spain CH-47D fleet to CH-47F standard |url=https://www.flightglobal.com/news/articles/boeing-to-upgrade-spain-ch-47d-fleet-to-f-standard-454783/ |website=Flight Global |access-date=4 January 2019 |archive-url=https://archive.today/20190104213912/https://www.flightglobal.com/news/articles/boeing-to-upgrade-spain-ch-47d-fleet-to-f-standard-454783/ |archive-date=4 January 2019 |location=Singapore |date=4 January 2019 |url-status=live}}</ref> By 2023, thirteen CH-47D were upgraded to CH-47F, and additionally, four new-built CH-47F were acquired.<ref>{{Cite web |date=2023-07-23 |title=Spain prefers Boeing CH-47F Block I heavy helicopters, buys 18th |url=https://bulgarianmilitary.com/2023/07/23/spain-prefers-boeing-ch-47f-block-i-heavy-helicopters-buys-18th/ |access-date=2024-04-06 |language=en-US}}</ref>