Editing McDonnell Douglas DC-10 (section)

==Development==
===Background===
{{multiple image
 |align = right
 |image1 = McDonnell Douglas DC-10-30, Monarch Airlines JP342549.jpg
 |width1 = 180
 |alt1 =
 |image_caption1 =
 |image2 = S2-ACR final flight DC10 BHX FLIGHT BG8 (12732029803).jpg
 |width2 = 189
 |alt2 =
 |image_caption2 =
 |footer = The 3-4-3 (left) and 2-5-2 (right) seating configuration
}}

Following an unsuccessful proposal for the [[United States Air Force]]'s [[Lockheed C-5 Galaxy|CX-HLS (Heavy Logistics System)]] in 1965, [[Douglas Aircraft Company|Douglas Aircraft]] began design studies based on its CX-HLS submission. The aviation author John H. Fielder notes that the company was under competitive pressure to produce a [[wide-body aircraft]], having been somewhat slow in the previous decade to introduce its first [[jetliner]]s.<ref name="fielder 12">{{harvnb|Fielder|Birsch|1992|pp=1–2}}</ref><ref name="norriswagner 910">{{harvnb|Norris|Wagner|1999|pp=9–10}}</ref> In 1966, [[American Airlines]] offered a specification to manufacturers for a twin-engine wide-body aircraft smaller than the [[Boeing 747]] yet capable of flying similar long-range routes from airports with shorter runways; this specification would be highly influential in the design of what would become the DC-10.<ref name="norriswagner 34">{{harvnb|Norris|Wagner|1999|p=34}}</ref>{{sfn|Francillon|1990|pp=275–276}} It would become [[McDonnell Douglas]]'s first commercial [[airliner]] after the merger between [[McDonnell Aircraft Corporation]] and Douglas Aircraft Company in 1967.<ref name=Waddington_p06>{{harvnb|Waddington|2000|pp=6–18}}</ref><ref name="norriswagner 36">{{harvnb|Norris|Wagner|1999|p=36}}</ref>

An early DC-10 design proposal was for a four-engine double-deck wide-body jet airliner with a maximum seating capacity of 550 passengers and similar in length to a [[Douglas DC-8|DC-8]]. The proposal was shelved in favor of a trijet single-deck wide-body airliner with a maximum seating capacity of 399 passengers, and similar in length to the DC-8 Super 60.{{sfn|Endres|1998|p=13}} The choice of three engines was influenced by surveys of potential customers other than American Airlines, together with a desire to enhance [[hot and high]] climb performance after an engine failure—a serious concern at [[Stapleton International Airport]], which was heavily utilized by [[United Airlines]], one of the major anticipated buyers.{{sfn|Francillon|1990|p=276}} Large portions of the detailed design work, particularly that of the fuselage, were [[subcontract]]ed to external companies, such as the American aerospace company [[Convair]].<ref name="fielder 4165">{{harvnb|Fielder|Birsch|1992|pp=4, 165}}</ref> The legal relationship between McDonnell Douglas, Convair, and the [[Federal Aviation Administration]] (FAA) would later serve to complicate matters; specifically, Convair was forbidden from contacting the regulator no matter the severity of any safety concerns it had in the DC-10's design.<ref name="fielder 34">{{harvnb|Fielder|Birsch|1992|pp=3–4}}</ref>

McDonnell Douglas management became seriously concerned about the viability of the DC-10 after learning about the competing [[Lockheed L-1011 TriStar|Lockheed L-1011]], which was very similar and was being offered to the same customers.{{sfn|Francillon|1990|p=276}} On February 19, 1968, in what was supposed to be a knockout blow to [[Lockheed Corporation|Lockheed]], [[George A. Spater]], President of American Airlines, and [[James Smith McDonnell|James S. McDonnell]] of McDonnell Douglas announced American Airlines' intention to acquire the DC-10. This was a shock to Lockheed and there was general agreement within the U.S. aviation industry that American Airlines had left its competitors at the starting gate. According to Fielder, McDonnell Douglas had been urgently pursuing the DC-10's completion in light of the prospective competition and the high financial stakes involved.<ref name="fielder 2"/> Together with American Airlines' announcement of the DC-10 order, it was also reported that American Airlines had declared its intention to have the British [[Rolls-Royce RB211]] turbofan engine on its DC-10 airliners.<ref>{{harvnb|Porter|2013}}{{page needed|date=May 2023}}</ref> The DC-10 was first ordered by launch customers American Airlines with 25 orders, and United Airlines with 30 orders and 30 options in 1968.{{sfn|Endres|1998|p=16}}<ref>[https://news.google.com/newspapers?id=Yd0yAAAAIBAJ&sjid=0lwDAAAAIBAJ&pg=7174,6365434&dq=airbus&hl=en "American Orders 25 'Airbus' Jets."] {{Webarchive|url=https://web.archive.org/web/20211104142745/https://news.google.com/newspapers?id=Yd0yAAAAIBAJ&sjid=0lwDAAAAIBAJ&pg=7174,6365434&dq=airbus&hl=en |date=November 4, 2021}} ''St. Petersburg Times'', February 20, 1968. Accessed: May 7, 2022.</ref><ref name="norriswagner 38">{{harvnb|Norris|Wagner|1999|p=38}}</ref> The DC-10's similarity to the Lockheed L-1011 in design, passenger capacity, and launch date resulted in a sales competition that affected the profitability of both aircraft.<ref name="norriswagner 369">{{harvnb|Norris|Wagner|1999|pp=36–39}}</ref>

===Into flight===
[[File:McDonnell Douglas DC-10 Prototype Landing.jpg|thumb|A prototype during flight testing, the DC-10 made its first flight on August 29, 1970.]]
On August 29, 1970, the first DC-10, a series 10, conducted its [[maiden flight]].{{sfn|Endres|1998|pp=25–26}} An extensive flight test program was carried out, totaling 929 flights and 1,551 flight hours; the test program was not incident-free: during one ground test in 1970, an outwardly-opening cargo door blew out and resulted rapid pressurization changes that caused the main cabin's floor to collapse.<ref name="fielder 2-3">{{harvnb|Fielder|Birsch|1992|pp=2–3}}</ref><ref name="endres 28"/> This discovery and first effort at rectification led to a contract dispute between McDonnell Douglas and Convair over what changes were necessary and financial liability. Fielder alleges that McDonnell Douglas consistently sought to minimize and postpone any design changes to the DC-10, although this attitude was not an explicit policy.<ref name="fielder 2390">{{harvnb|Fielder|Birsch|1992|pp=23, 90}}</ref> In July 1971, Convair outlined the situation in a formal memo; almost a year later, it internally expressed concerns that the inadequate resolution would lead to loss of aircraft.<ref name="fielder 165">{{harvnb|Fielder|Birsch|1992|pp=90–91, 165}}</ref> Tragically, the initial rectification work would prove to be inadequate.<ref name="fielder 4">{{harvnb|Fielder|Birsch|1992|p=4}}</ref>

On July 29, 1971, the FAA issued the [[type certificate]] for the DC-10, permitting its entry into revenue service.<ref name="endres 28">{{harvnb|Endres|1998|p=28}}</ref> It entered commercial service with American Airlines on August 5, 1971, with the initial flight being a round-trip flight between Los Angeles and Chicago. United Airlines also commenced DC-10 flights later that same month.{{sfn|Endres|1998|p=52}} American's DC-10s were configured to seat a maximum of 206 passengers while United's seated 222; both had six-across seating in first-class and eight-across (four pairs) in coach.<ref>''Aviation Daily'' July 29, 1971.</ref> They operated the first version of the DC-10, referred to as the "domestic" series 10, which had a range of {{convert|3800|mi|nmi km}} with a typical passenger load and a range of {{convert|2710|mi|nmi km}} with maximum payload.

===Further development===
[[File:McDonnell Douglas DC-10-10, Continental Airlines JP6751857.jpg|thumb|Continental Airlines six-abreast interior in 1973]]
Various models of the DC-10 promptly followed, such as the series 15, which had a typical load range of {{convert|4350|mi|nmi km}}.<ref name=DC-10_tech_specs>[http://www.boeing.com/commercial/dc-10/tech.html "DC-10 Technical Specifications."] {{webarchive |url=https://web.archive.org/web/20070204040205/http://www.boeing.com/commercial/dc-10/tech.html |date=February 4, 2007}} ''Boeing.'' Retrieved: March 12, 2011.</ref>{{sfn|Endres|1998|pp=32–33}} The series 20 was powered by [[Pratt & Whitney JT9D]] turbofan engines, whereas the series 10 and 30 engines were [[General Electric CF6]]. Prior to taking delivery of the aircraft, Northwest's president asked that the "series 20" aircraft be redesignated "series 40" because the airliner was much improved over the original design. The FAA issued the certification for the series 40 on October 27, 1972.<ref name=Waddington_p70>{{harvnb|Waddington|2000|p=70}}</ref><ref name="norriswagner 36"/> In 1972, the DC-10's listed unit cost was reportedly US$20M<ref name=Flight10aug1972>{{cite magazine |url= https://www.flightglobal.com/pdfarchive/view/1972/1972%20-%202020.html |title= Airliner price index |magazine= Flight International |date= August 10, 1972 |page= 183 |access-date= January 9, 2018 |archive-date= January 9, 2018 |archive-url= https://web.archive.org/web/20180109181149/https://www.flightglobal.com/pdfarchive/view/1972/1972%20-%202020.html |url-status= live}}</ref> (${{Format price|{{inflation|USD|20000000|1972}}}} in {{Inflation-year|USD}} prices).

The series 30 and 40 were longer-range "international" versions. The main visible difference between the models is that the series 10 has three sets of landing gear (one front and two main) while the series 30 and 40 have an additional centerline main gear. The center main two-wheel landing gear (which extends from the center of the fuselage) was added to distribute the extra weight and for additional braking. The series 30 had a typical load range of {{convert|6220|mi|nmi km}} and a maximum payload range of {{convert|4604|mi|nmi km}}. The series 40 had a typical load range of {{convert|5750|mi|nmi km}} and a maximum payload range of {{convert|4030|mi|nmi km}}.<ref name=DC-10_tech_specs/>{{sfn|Endres|1998|pp=34–35}}

The DC-10 had two engine options and introduced longer-range variants a few years after entering service; these allowed it to distinguish itself from its main competitor, the L-1011. Further models and derivatives of the DC-10 have been considered; perhaps the most radical of these being an unpursued twin-engined model akin to the [[Airbus A300]].<ref name="norriswagner 71">{{harvnb|Norris|Wagner|1999|p=71}}</ref><ref name="eden 147">{{harvnb|Eden|2016|p=147}}</ref> However, following a spate of fatal accidents, particularly the [[American Airlines Flight 191]] crash (the deadliest aviation accident in US history) orders for the DC-10 had nosedived by 1980, the type having garnered a poor reputation that was widespread amongst the traveling public as well as prospective operators.<ref name="nytimes july1989">{{Cite news |url = https://www.nytimes.com/1989/07/20/us/troubled-history-of-the-dc-10-includes-four-major-crashes.html |title = Troubled History of the DC-10 Includes Four Major Crashes |last = Bradsher |first = Keith |date = July 20, 1989 |work = [[The New York Times]] |language = en-US |issn = 0362-4331 |access-date = December 20, 2017 |archive-date = December 19, 2017 |archive-url = https://web.archive.org/web/20171219211751/http://www.nytimes.com/1989/07/20/us/troubled-history-of-the-dc-10-includes-four-major-crashes.html |url-status = live}}</ref><ref name="eden 1447">{{harvnb|Eden|2016|pp=144–147}}</ref> Competitive pressure had also played a role, Boeing in particular had developed the [[Boeing 747SP|747SP]] variant specifically to better compete with the DC-10 and L-1011.<ref name="eden92">{{cite book|editor-last=Eden |editor-first=Paul|title=Civil Aircraft Today |year=2008 |publisher=Amber Books |pages=96–97}}</ref>

In December 1988, the 446th and final DC-10 rolled off the [[Long Beach, California]] Products Division production line and was delivered to [[Nigeria Airways]] in July 1989.<ref name=mdc_history>{{cite web |url=http://www.boeing.com/history/mdc/dc-10.htm |title=McDonnell Douglas DC-10/KC-10 Transport |url-status=dead |website=boeing.com |archive-url=https://web.archive.org/web/20060312023701/http://www.boeing.com/history/mdc/dc-10.htm |archive-date=March 12, 2006 |access-date=February 28, 2006}}</ref><ref name=Jet_production_list>Roach, John and Anthony Eastwood. [https://web.archive.org/web/19980623111342/http://www.tahs.com/ "Jet Airliner Production List, Volume 2."] ''The Aviation Hobby Shop'' online, July 2006. Retrieved: September 19, 2010.</ref> The production run had exceeded the 1971 estimate of 438 deliveries needed to break even on the program;<ref>{{cite journal |journal = Air Progress |title = Air Progress |date = September 1971 |page = 16}}</ref> however, according to Fielder, the DC-10 had not reached the breakeven point by the end of production.<ref name="fielder 2">{{harvnb|Fielder|Birsch|1992|p=2}}</ref> As the final DC-10s were delivered, McDonnell Douglas started production of its successor, the [[McDonnell Douglas MD-11|MD-11]], which was essentially a stretched derivative of the DC-10-30.{{sfn|Steffen|1998|p=120}}<ref name="norriswagner 64">{{harvnb|Norris|Wagner|1999|p=64}}</ref>

In the late 1980s, international travel was on the rise due to lower [[Price of oil|oil prices]] and more [[economic freedom]], leading to a surge in demand for wide-body airliners. However, the [[Boeing 747-400]], MD-11, [[Airbus A330]]/[[Airbus A340|A340]], and soon-to-be-built [[Boeing 777]] were all behind schedule and could not fully meet the demand. Production of first-generation widebodies like the [[Boeing 747-100]]/[[Boeing 747-200|200]]/[[Boeing 747-300|300]], L-1011, and DC-10 had ended, so the value of used DC-10-30s almost doubled, rising from less than $20 million to almost $40 million.<ref>{{cite news |url = http://www.aircraftvaluenews.com/transitioning-product-line-impacts-values-of-outgoing-models/ |title = Transitioning Product Line Impacts Values of Outgoing Models |author = Aircraft Value News |date = November 12, 2018 |access-date = November 13, 2018 |archive-date = November 13, 2018 |archive-url = https://web.archive.org/web/20181113165723/http://www.aircraftvaluenews.com/transitioning-product-line-impacts-values-of-outgoing-models/ |url-status = live}}</ref>