View source for BAC One-Eleven

{{Short description|Retired British short-range jet airliner (1963–2019)}}
{{Redirect2|One Eleven|1-11|the record label|One Eleven Records|other uses|1/11 (disambiguation){{!}}1/11}}
{{Use dmy dates|date=April 2020}}
{{Use British English|date=February 2012}}
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{{Infobox aircraft
 |name= One-Eleven
 |image= File:TAROM BAC 1-11-500; YR-BCI@ZRH;02.10.1995 (8353902456).jpg
 |caption= A [[TAROM]] One-Eleven in 1995
 |alt=a low wing airliner powered by two aft-mounted engines
 |type= Short-range [[jet airliner]]
 |manufacturer= {{ubl|[[British Aircraft Corporation]]|[[Romaero]]}}
 |national_origin = United Kingdom
 |designer=
 |first_flight= 20 August 1963<ref name="Hill 1999, p. 31">Hill 1999, p. 31.</ref>
 |introduction= 1965 with [[British United Airways]]
 |retired= 7 May 2019
 |status= Retired<ref name="auto">{{Cite web|url=https://worldairlinenews.com/2019/05/08/northrop-grumman-retires-its-bac-1-11-n164w-the-end-of-an-era/|title=Northrop Grumman retires its BAC 1-11 N164W, the end of an era|first=Bruce|last=Drum|date=8 May 2019}}</ref>
 |primary_user=[[British Airways]]
 |more_users={{ubl|[[American Airlines]]|[[Braniff Airways]]|[[British United Airways]]}}
 |produced={{ubl|1963–1982 (United Kingdom)|1982–1989 (Romania)}}
 |number_built=244
 |variants=
}}

The '''BAC One-Eleven''' ('''BAC-111''', '''BAC 1-11''') is a retired early [[jet airliner]] produced by the [[British Aircraft Corporation]] (BAC).
<!--Development-->
Conceived by [[Hunting Aircraft]] as a 30-seat jet, before its merger into BAC in 1960, it was launched as an 80-seat airliner with a [[British United Airways]] (BUA) order on 9 May 1961.<!-- see Hill 1999, p. 16-->
The prototype conducted its [[maiden flight]] on 20 August 1963, and it was first delivered to BUA on 22 January 1965.
The 119-seat, stretched 500 series was introduced in 1967.
Total production amounted to 244 until 1982 in the [[United Kingdom]] including 1982 to 1989 in [[Romania]] where nine '''Rombac One-Elevens''' were licence-built by [[Romaero]].

<!--design-->
The [[short haul]], [[narrowbody aircraft]] was powered by aft-mounted [[Rolls-Royce Spey]] low-bypass turbofans, a configuration similar to the earlier [[Sud Aviation Caravelle]] and later [[McDonnell Douglas DC-9|Douglas DC-9]].
<!--Operational history-->
It competed with early [[Boeing 737]] models and was used by British, US, and European airlines, including Romanian operators.
It was replaced by the newer [[Airbus A320 family|Airbus A320]] and later 737 variants, as well as by the [[Bombardier CRJ200]] regional jet.
[[aircraft noise|Noise]] restrictions accelerated its transition to African carriers in the 1990s, and the last BAC One-Eleven was retired in 2019.

==Development==

===Early development===
[[File:Hunting 107.png|thumb|The initial Hunting 107 concept from [[Hunting Aircraft]]]]

In the 1950s, although the pioneering [[de Havilland Comet]] had suffered disasters in service, strong passenger demand had been demonstrated for jet propulsion. Several manufacturers raced to release passenger jets, including those aimed at the short-haul market, such as the [[Sud Aviation Caravelle]].<ref>Hill 1999, pp. 6-7.</ref> In July 1956, [[British European Airways]] published a paper calling for a "second generation" jet airliner to operate beside their existing [[turboprop]] designs. This led to a variety of designs from the British aerospace industry. [[Hunting Aircraft]] started design studies on a jet-powered replacement for the successful [[Vickers Viscount]], developing the 30-seat '''Hunting 107'''. Around the same time, Vickers started a similar development of a 140-seat derivative of its [[Vickers VC10|VC10]] project, the '''VC11'''. Many other aviation firms also produced designs.<ref>Hill 1999, pp. 8-10.</ref>

In 1960 Hunting, under British government pressure, merged with [[Vickers-Armstrongs]], [[Bristol Aeroplane Company|Bristol]], and [[English Electric]] to form [[British Aircraft Corporation]] (BAC). The new BAC decided that the Hunting project had merit, but that there would be little market for a 30-seat jet airliner.<ref>Hill 1999, pp. 13-15.</ref> The design was reworked into the BAC 107, a 59-seat airliner powered by two {{convert|7000|lbf|kN}} [[Bristol Siddeley]] BS75 [[turbofan]] engines.<ref name="database p68">Chorlton ''Aeroplane'' November 2012, p. 68.</ref> BAC also continued development of the larger, 140-seat VC-11 development of the [[Vickers VC10]] which it had inherited.<ref name="Andrews vickers p576-7">Andrews, C. F. and E. B. Morgan. ''Vickers Aircraft since 1908''. London: Putnam, 1988. {{ISBN|0-85177-815-1}}, pp. 576–577.</ref> Other competing internal projects, such as the [[Bristol Type 200]], were quickly abandoned following absorption of Hunting into BAC.<ref>Hill 1999, pp. 14-15.</ref>

[[File:RR Spey.jpg|thumb|The selected [[Rolls-Royce Spey]] low-bypass [[turbofan]]]]

Market research showed the 59-seat BAC 107 was too small, and the design was reworked in 1961, with passenger capacity growing to 80 seats, and BS75s being discarded in favour of [[Rolls-Royce Spey]]s.<ref>Hill 1999, p. 15.</ref> The revised design was redesignated the BAC 111 (later known as the One-Eleven), with BAC abandoning the VC11 project to concentrate on the more promising One-Eleven. Unlike contemporary British airliners such as the [[Hawker Siddeley Trident]], the One-Eleven was not designed specifically to meet the needs of the state-owned [[British European Airways]] or [[British Overseas Airways Corporation]], but on the needs of airlines around the world, and BAC expected orders for as many as 400.<ref name="database p70-1">Chorlton ''Aeroplane'' November 2012, pp. 70–71.</ref>

On 9 May 1961 the One-Eleven was publicly launched when British United Airways placed the first order for ten One-Eleven 200s.<ref>Hill 1999, p. 16.</ref> On 20 October [[Braniff International Airways]] in the United States ordered six.<ref name="database p71">Chorlton ''Aeroplane'' November 2012, p. 71.</ref> [[Mohawk Airlines]] sent representatives to Europe seeking out a new aircraft to bring them into the jet era, and on 24 July 1962 concluded an agreement for four One-Elevens.<ref>Lewis 2000 p. 311.</ref> Orders followed from [[Kuwait Airways]] for three, and [[Central African Airways]] for two. Braniff subsequently doubled their order to 12, while Ireland's [[Aer Lingus]] ordered four. [[Western Airlines]] ordered ten but later cancelled.<ref name="database p71"/> [[Bonanza Air Lines]] also ordered three in 1962<ref>{{Cite magazine |url=http://www.flightglobal.com/pdfarchive/view/1962/1962%20-%202599.html |title=World Air News: One-Elevens for Bonanza |archive-url=https://web.archive.org/web/20140201211123/http://www.flightglobal.com/pdfarchive/view/1962/1962%20-%202599.html |archive-date= 2014-02-01 |magazine=[[Flight International]] |volume= 82 |number=2800 |date= 8 November 1962 |page= 728}}</ref> but was stopped by the US [[United States government role in civil aviation#Civil Aeronautics Authority|Civil Aeronautics Board]] (CAB), which claimed that subsidies would be needed to operate a jet on Bonanza's routes, an action claimed by some at the time to be [[protectionism]].<ref>[http://www.flightglobal.com/pdfarchive/view/1963/1963%20-%201256.html "Air Commerce: Bonanza's Bid for DC-9s"]. ''Flight International'', Vol. 84 No. 2836, 18 July 1963. p. 84.</ref> The CAB also stopped [[Frontier Airlines (1950–1986)|Frontier Airlines]] and [[Ozark Air Lines]] from ordering One-Elevens, although allowing Ozark to order the similar Douglas DC-9 and Frontier to order [[Boeing 727-100]]s. The CAB had also unsuccessfully tried to block Mohawk's orders.<ref name="database p71"/><ref>Lewis 2000, p. 312.</ref>

In May 1963, BAC announced the One-Eleven 300 and 400. The new versions used the Mk. 511 version of the Spey with increased power, allowing more fuel upload and hence longer range. The difference between the 300 and 400 lay in the equipment and [[avionics]], the 400 intended for sales in the United States and thus equipped with US instruments.<ref name="database p71"/> On 17 July 1963, [[American Airlines]] ordered 15 aircraft, bringing the total to 60, plus options for 15.<ref>[http://www.flightglobal.com/pdfarchive/view/1963/1963%20-%201291.html "American Orders One-Elevens"]. ''Flight International'' Vol. 84 No. 2837, 25 July 1963. p. 117.</ref><ref name="Willis p64">Willis ''Air International'' October 2006, p 64.</ref> American Airlines eventually bought 30 of the 400-series, making the airline the largest customer of One-Elevens.

===Prototypes===
[[File:G-ASJI 1 One-Eleven 201 British United LGW 14MAY66 (6785552209).jpg|thumb|The first delivery was to [[British United Airways]] on 22 January 1965.]]

The prototype (''G-ASHG'') rolled out of [[Bournemouth Airport|Hurn]] assembly hall on 28 July 1963, at which point BAC had received orders for the type from a number of operators. On 20 August 1963, the prototype conducted its first flight, painted in BUA livery. The first flight had taken place almost a year before the Douglas DC-9, a rival American jetliner; BAC considered the One-Eleven to hold a technological edge.<ref name="Hill 1999, p. 31"/> The One-Eleven's lead was of significant importance commercially, since, as shown by the Bonanza Air Lines case, US authorities could refuse to approve sales of foreign aircraft to domestic airlines where an American alternative existed (Bonanza ended up ordering and operating the DC-9). Test flying was conducted by Squadron Leader [[Dave Glaser]].

The One-Eleven prototype, flown by test pilot [[Mike Lithgow]], [[1963 BAC One-Eleven test crash|crashed on 22 October 1963]] during [[Stall (flight)|stall]] testing, with the loss of all on board. The investigation led to the discovery of what became known as [[Stall (flight)#Deep stall|deep stall]] or superstall, a phenomenon caused by reduced airflow to the [[tailplane]] caused by the combined blanking effects of the wing and the aft-mounted engine [[nacelle]]s at high [[angle of attack|angles of attack]], which prevents recovery of normal (nose-down) flight.<ref name=Deepstall>''Report on the Accident to B.A.C. One-Eleven G-ASHG at Cratt Hill, near Chicklade, Wiltshire on 22 October 1963'', Ministry of Aviation C.A.P. 219, 1965</ref> To prevent such stalls, BAC designed and added devices known as [[stick shaker]]s and [[stick pusher]]s to the One-Eleven's control system.<ref>Sorlucco 2005, pp. 77-78.</ref> It also redesigned the wing's [[Airfoil|leading edge]] to smooth airflow into the engines and over the tailplane. The specially modified aircraft used for testing this problem is now preserved at [[Brooklands Museum]].

Despite the crash, testing continued and customer confidence remained high. American Airlines and Braniff took up their optional orders and placed more in February 1964. Further orders came from Mohawk, [[Philippine Airlines]] and German businessman [[Helmut Horten]], who ordered the first executive modification of the aircraft. By the end of 1964, 13 aircraft had rolled off the production line. The One-Eleven was [[Type certificate|certified]] and the first handover, of ''G-ASJI'' to BUA, was on 22 January 1965. After several weeks of route-proving flights, the first revenue service flew on 9 April from [[Gatwick Airport|Gatwick]] to [[Genoa]]. Braniff took delivery of its first aircraft on 11 March, while Mohawk received its first on 15 May. Deliveries continued, and by the end of 1965 airlines had received 34 aircraft. Demand remained buoyant, with a second production line set up at [[Weybridge]]{{dash}}producing thirteen 1-11s between 1966 and 1970.

===The One-Eleven 500, 510ED and 475===
[[File:British Aircraft Corporation BAC 1-11 Series 523FJ, European Aviation (EAL) JP6105232.jpg|thumb|Introduced in 1967, the 500 series are stretched by {{cvt|13.5|ft}}.]]

In 1967 a larger 119-seat version was introduced as the One-Eleven 500 (also known as Super One-Eleven). This "stretched" version was delayed for at least a year while its launch customer BEA assessed its requirements. This gave competing US aircraft (the Douglas DC-9 and Boeing 737) the opportunity to compensate for the One-Eleven's early penetration of the US domestic market. The British aircraft's initial one-year advantage now turned into a one-year delay, and the stretched series 500 failed to sell in the US. The type saw service with [[Cayman Airways]] and [[Leeward Islands Air Transport]] (LIAT) in the Caribbean with Cayman Airways operating the series 500 on scheduled services to Houston, Texas (IAH) and Miami, Florida (MIA), and LIAT flying its series 500s into San Juan, Puerto Rico (SJU). [[Bahamasair]] also operated the stretched 500 model with service between Nassau (NAS) and Miami among other routes while Guatemalan carrier [[Aviateca]] operated its series 500 aircraft into both Miami and New Orleans, Louisiana (MSY).<ref>http://www.timetableimages.com, 1 Nov. 1971 Aviateca system timetable</ref> Costa Rican airline [[LACSA]] operated the series 500 as well on its services to Miami.<ref>http://www.timetableimages.com, 31 May 1973 LACSA system timetable</ref> Another air carrier which operated the series 500 into Miami was [[Belize Airways]] Ltd.<ref>[http://www.timetableimages.com/i-s/st80ca.jpg Timetables] timetableimages.com</ref>

Compared with earlier versions, the One-Eleven 500 was longer by 8&nbsp;ft 4in (2.54 m) ahead of the wing and 5&nbsp;ft 2in (1.57 m) behind it. The wing span was increased by 5&nbsp;ft (1.5 m), and the latest Mk. 512 version of the Spey was used. The new version sold reasonably well across the world, particularly to European charter airlines. In 1971 it received an incremental upgrade to reduce [[Drag (physics)|drag]] and reduce [[runway]] requirements.

[[File:BAC 111-510ED One-Eleven, AB Airlines (European Aircharter - EAL) AN0528338.jpg|thumb|The 510ED cockpit, similar to the [[Hawker Siddeley Trident]]]]

BEA/British Airways 500 series aircraft (denoted ''One-Eleven 510ED'') varied significantly from other One-Elevens, at BEA's request. The One-Eleven 510ED had a modified [[cockpit]] which incorporated instrumentation and avionics from or similar to that of the [[Hawker Siddeley Trident]], for better commonality with the type. Their additional equipment included a more sophisticated [[autopilot]], which allowed [[autoland]] in [[Instrument Landing System#CAT II|CAT II]] and included an autothrottle. The modifications went as far as reversing the "on" position of most switches to match that of the Trident; indeed, the 510ED was so different from other One-Elevens and 500 series aircraft that a different [[Pilot licensing in the United Kingdom|type rating]] was required to fly it.

Having faced competition from US aircraft by 1966, by 1970 the One-Eleven also faced competition from newer, smaller aircraft such as the [[Fokker F28 Fellowship]]. The F28 was lighter, less complex, and cheaper. The One-Eleven 475 of 1970 was launched to compete with the F28. It combined the 400 fuselage with the higher power and larger wing of the 500 and was intended for [[hot and high]] as well as rough airfield operations; however only ten One-Eleven Mk 475s were sold with one airline being [[Faucett Peru]] which operated its series 475 aircraft on scheduled domestic services into several airports with unpaved gravel runways in Peru.<ref>{{cite web | url=http://www.airliners.net/photo/Faucett/BAC-111-476FM-One-Eleven/2695729/L | title=Aviation Photo #2695729: BAC 111-476FM One-Eleven{{dash}}Faucett }}</ref> In 1977, the One-Eleven 670, a quiet and updated 475, was offered to the Japanese domestic market, also failing to sell.

===Proposed developments===
{{unreferenced section|date=November 2019}}
[[File:BAC X-Eleven.jpg|thumb|The BAC X-Eleven would have been stretched for up to 160 seats and powered by larger [[CFM56]] or [[JT10D]] turbofans.]]

Total deliveries for 1965 were 34 aircraft,<ref name="database p78">Chorlton ''Aeroplane'' November 2012, p. 78.</ref> while 200 aircraft had been built by the end of 1971.<ref name="database p78"/> At this point orders slowed to a trickle, with production being suspended in 1975, although marketing and design continued, and it was always planned to restart production when sufficient orders had been received.<ref name="ai179p8,10">''Air International'' January 1979, pp. 8, 10</ref> BAC restarted production in 1977 as a result of an order for five aircraft by the Romanian airline [[Tarom]].<ref name="ai179p10">''Air International'' January 1979, p. 10</ref> British production continued until 1984, with a total of 235 aircraft built in Britain.<ref name="database p78"/> There were two reasons why the production line was kept open for just 35 aircraft delivered over 11 years: first, BAC hoped that Rolls-Royce would develop a quieter and more powerful version of the Spey engine, making possible further One-Eleven developments; second, throughout the early part of the period [[Romania]] was negotiating to buy the entire One-Eleven programme and transfer production of the type to [[Bucharest]].

By 1974, BAC invested significant effort into launching the One-Eleven 700. This had a longer [[fuselage]] with a 134-seat interior and the projected {{convert|16900|lbf|kN|abbr=on}} Spey 606 engine producing greater power and less noise.<ref name="aero212p37">Payne ''Aeroplane'' February 2021, p. 37.</ref><ref name="jawa75p195">Taylor 1975, p. 195.</ref> The 700J was planned for the Japanese market, with the same stretched fuselage and engines as the 700 and a new high-lift wing for operation into regional airports with short runways.<ref name="ai179p10"/> The 700 was approximately the same size as the latest DC-9s and 737s and would have been available in time to prevent large-scale defections by One-Eleven clients to McDonnell-Douglas and Boeing. Rolls-Royce was still recovering from bankruptcy, however, and the uprated Spey failed to materialise. An altogether less ambitious 700 made a reappearance in 1978 as a 500 with specially "hush-kitted" Speys which would be replaced by the proposed RB432 in the mid-1980s. This was offered to [[British Airways]] in competition with Boeing 737-200s, but was ultimately rejected.

In 1975, BAC launched the One-Eleven 800, a further stretched aircraft to be powered by two {{convert|22000|lbf|kN|abbr=on}} [[CFM International CFM56]] high-bypass turbofans and seating 144 to 161 passengers,<ref name="aero212p38">Payne ''Aeroplane'' February 2021, p. 38.</ref><ref name="jawa75p195"/> but this project was abandoned in 1976 in favour of a new derivative of the One-Eleven with a wider fuselage capable of six-abreast seating. This new airliner was unveiled later that year as the X-Eleven, which would be powered by two CFM-56s or Pratt & Whitney JT10D engines and seat up 166 passengers.<ref name="aero212p389">Payne ''Aeroplane'' February 2021, pp. 38–39.</ref> In 1977, BAC merged with [[Hawker Siddeley]] to form [[British Aerospace]] (BAe) and the new company was faced with the choice of developing the X-Eleven or joining European efforts to design an-all new aircraft. In the end, BAe became a full member of Airbus, and the X-Eleven was abandoned, with the European alternative becoming the Airbus A320.<ref name="aero212p401">Payne ''Aeroplane'' February 2021, pp. 400–401.</ref>

The [[BAC Two-Eleven and Three-Eleven]] were British airliner studies proposed by the British Aircraft Corporation in the late 1960s which never made it to production.

===Rombac production===
[[File:ROMBAC 1-11 (YR-BRA).jpg|thumb|The first Rombac 1-11 was delivered to [[TAROM]] on 29 December 1982.]]

On 9 June 1979, Romanian president [[Nicolae Ceaușescu]] signed a contract for One-Eleven licence production in Romania. This was to involve the delivery of three complete One-Elevens (two 500-series aircraft and one 475 series) plus the construction of at least 22 in Bucharest, with the reduction of British (and thus increase of Romanian) content. It also involved Romanian production of [[Rolls-Royce Spey]] engines and certification of the aircraft to British standards by the [[Civil Aviation Authority (United Kingdom)|Civil Aviation Authority]]. A market for up to 80 Romanian-built aircraft was projected at the time, largely in China and other developing economies, and possibly [[Eastern Europe]]. The aircraft was redesignated '''Rombac 1-11'''.<ref name="database p80-1">Chorlton ''Aeroplane'' November 2012, pp. 80–81.</ref><ref name="JAWA82 p173">Taylor, John W. R. ''Jane's All The World's Aircraft 1982–83''. London: Jane's Yearbooks, 1982. {{ISBN|0-7106-0748-2}}, p. 173.</ref> The Spey 512-14 DW engines were produced under license by Turbomecanica Bucharest.<ref>{{Cite web|url=https://turbomecanica.ro/en/about-us/history/|title=History{{dash}}Turbomecanica Today{{dash}}The Beginnings of Turbomecanica|website=Turbomecanica|accessdate=8 May 2023}}</ref>

The first Rombac One-Eleven, (YR-BRA cn 401) a series 561RC, was rolled out at Romaero Băneasa factory on 27 August 1982 and first flew on 18 September 1982. Production continued until 1989 at a much slower pace than foreseen in the contract. Nine aircraft were delivered, with the 10th and 11th aircraft on the production line being abandoned when they were 85% and 70% complete.<ref name="database p80-1"/><ref name="pilling p213-4"/> The first aircraft was delivered to [[TAROM]] on 29 December 1982.<ref name="pilling p213-4"/> The Romanian carrier took delivery of all but two of the aircraft produced, the remaining two going to [[Romavia]], the last of which (YR-BRI cn 409) was delivered on 1 January 1993.

There were three reasons why the Rombac initiative failed. Romania's economy and international position deteriorated to the point where supplies needed for One-Eleven manufacturing slowed to a trickle, with [[hard currency]] restrictions delaying the delivery of components sourced outside Romania;<ref name="database p80-1"/><ref name="pilling p213-4"/> the market foreseen by the Romanians failed to show an interest, though some Rombac machines were leased to European operators. The One-Eleven's noise level and fuel economy failed to keep pace with US and West European competition.

Adopting a new engine would have resolved noise and fuel economy issues. Following the [[Romanian Revolution|fall of the Ceaușescu regime]], plans were made to restart production using the [[Rolls-Royce Tay (turbofan)|Rolls-Royce Tay]]. British [[Aircraft lease|aircraft leasing]] company Associated Aerospace agreed a $1 billion deal to purchase 50 Tay-powered One-Elevens fitted with a new electronic [[glass cockpit]] for onward leasing to Western customers. The [[liquidation]] of Associated Aerospace in April 1991 stopped this deal. Despite this setback, Rombac continued to try to sell the One-Eleven, with US operator [[Kiwi International Air Lines]] placing a firm order for 11 Tay-engined aircraft with options for an additional five, but these plans never happened.<ref name="database p80-1"/><ref name="pilling p213-4">Pilling, Mark. "Whatever happened to the Romanian One-Eleven?". ''[[Air International]]'', Vol. 43 No. 4, October 1992. pp.&nbsp;212–214. {{ISSN|0306-5634}}, pp. 213–214.</ref><ref>Beech, Eric. [http://www.flightglobal.com/pdfarchive/view/1990/1990%20-%200896.html "Rombac Tay 1-11s offered for lease"]. ''Flight International'', Vol. 137, No. 4209, 28 March–3 April 1990, pp. 4–5.</ref><ref>[http://www.flightglobal.com/pdfarchive/view/1991/1991%20-%202344.html "Commercial Aircraft of the World: Rombac"]. ''Flight International'', Vol. 140 No. 4283, 4–10 September 1991, pp. 70–71.</ref><ref>Daly, Kieron. [http://www.flightglobal.com/pdfarchive/view/1993/1993%20-%201070.html "Kiwi banks on Romanian cash"]. ''Flight International'', Vol 143, No. 4369, 12–18 May 1993. p. 11.</ref>

==Operational history==
[[File:Line-up of American Airlines BAC 111-401AK One-Eleven at LaGuardia Airport.jpg|thumb|Several [[American Airlines]] BAC One-Elevens at [[LaGuardia Airport]]]]

Once in service, the One Eleven found itself in competition with the Douglas DC-9, and was joined by another competitor, the Boeing 737, only a year after its introduction.<ref name=Gunn1999/> Advantages over the DC-9 included a lower unit cost. The DC-9 offered more seating, and its engines were interchangeable with those on the Boeing 727. These factors led to [[Trans Australia Airlines]] choosing to purchase the DC-9 instead.<ref name=Gunn1999>Gunn, John. "Contested Skies: Trans-Australian Airlines, Australian Airlines." ''University of Queensland Press'', 1999. {{ISBN|0-7022-3073-1}}, pp. 203–205.</ref> In the US, the Civil Aeronautics Board was sceptical of smaller operators' need for jet aircraft and withheld financing, leading to several US customers cancelling their One-Eleven orders.<ref>Hill 1999, p. 25.</ref>

[[Mohawk Airlines]] became both the first American operator of the type and the first airline in the US to operate jet aircraft on short haul routes.<ref>Sorlucco 2005, p. 76.</ref> On 25 June 1965, Mohawk introduced its first One-Eleven into passenger service; by the end of the decade, the airline operated a fleet of 20 BAC One-Elevens.<ref>Lewis, 2000 p. 314.</ref> Buying the jets pushed Mohawk into debt and this, along with an economic downturn and [[strike action]], led to its forced merger with [[Allegheny Airlines]] which in turn continued to operate the One-Eleven.<ref>Lewis, 2000. pp. 317–318.</ref> In July 1963, [[American Airlines]] had placed an order for 15 400-series One-Elevens for £14 million; this was the first time American Airlines had purchased a foreign aircraft type for its fleet.<ref>Hill 1999, pp. 28-30.</ref> Braniff International Airways, another major US air carrier, also ordered the One-Eleven.<ref>{{Cite web |url=http://www.braniffpages.com/ |title=Archived copy |access-date=8 October 2019 |archive-url=https://web.archive.org/web/20181215173522/http://www.braniffpages.com/ |archive-date=15 December 2018 |url-status=dead }}</ref> [[Aloha Airlines]] selected the One-Eleven as its first jet type for interisland service in the [[Hawaiian Islands]].

Several British operators, including [[Dan Air]] and [[British Caledonian]], made extensive use of the type. Dan Air increased the number of One-Elevens it had in service in the 1970s, eventually replacing its aging [[de Havilland Comet]]s with the One-Eleven entirely in the 1980s. The type became the airline's main revenue generator.<ref>Hill 1999, pp. 147, 159.</ref> Dan Air would often lease One-Elevens, including Rombac-produced aircraft, to meet short-term demands. During periods of low demand Dan Air would lease its own One-Elevens to other operators. British Caledonian and Dan Air One-Elevens would often be exchanged between the two airlines on temporary and permanent arrangements. Passenger demand grew on several key One-Eleven routes, exceeding the Series 500's larger capacity during the 1980s, which began to force airlines to use other planes.<ref>Hill 1999, pp. 160, 162.</ref>

Before the formation of [[British Airways]] (BA), some predecessor companies, British European Airways and [[Cambrian Airways]], were operating the One-Eleven. Their fleets were inherited by BA. British Airways Regional Division found the performance of the One-Eleven more than adequate and sought to expand operations with the type, including further acquisitions, in the early 1970s in part to replace [[Vickers Viscount]]s. BA's 400-Series One-Elevens were all named after areas and locations in the [[The Midlands, England|English Midlands]], reflecting the type's new base at [[Birmingham Airport]].<ref>Hill 1999, pp. 104-105.</ref> BA ordered more Series-500 aircraft in the late 1970s and the airline received some of the last British-made One-Elevens.<ref>Hill 1999, pp. 116-117.</ref>

British Caledonian had begun replacing its One-Elevens with the new Airbus A320, when it was merged with British Airways in 1987 due to financial problems.<ref>Hill 1999, p. 147.</ref> In both Caledonian and British Airways service, the One-Elevens were a dominant type for the operator's European routes. BA proceeded to rationalise its fleets, retiring many overlapping types, the One-Eleven being gradually phased out for the more modern A320 and Boeing 737 jetliners. The last aircraft was removed from regular service with BA in October 1992.<ref>Hill 1999, p. 148.</ref> A number of ex-BA aircraft saw service with [[Maersk Air]] before, in turn, being replaced by the [[Bombardier CRJ200]] in the late 1990s.<ref name="Hill 1999, p. 152">Hill 1999, p. 152.</ref>

[[File:Ryanair Bucuresti Rombac 1-11-561RC One-Eleven Haafke-1.jpg|thumb|A [[Ryanair]] One-Eleven]]
In Ireland [[Aer Lingus]] flew One-Elevens for three decades, in both the scheduled and charter markets. The aircraft was used on less-busy European routes into the 1990s.<ref name="Hill 1999, p. 152"/> The One-Eleven was important in [[budget airline]] [[Ryanair]]'s early years: it had sought an aircraft for low-fare scheduled services from regional airports, and obtained One-Elevens. The first of these, a Rombac-produced 500-Series, entered service on the Dublin–Luton route on 1 December 1986. Ryanair's fleet expanded to six aircraft by 1988, with three leased from Romania.<ref>Hill 1999, pp. 152-153.</ref> These leased aircraft were later replaced with former BA One-Elevens. Ultimately Ryanair replaced the One-Eleven with the Boeing 737 in the mid-1990s.<ref>Hill 1999, pp. 153-154.</ref>

In April 1966, [[Philippine Airlines]] began operating One Elevens in revenue service. They eventually operated 12 of the later 500-Series. One of these aircraft suffered two separate in-flight bomb explosions, but was repaired each time and continued in service until 1992. In another high-profile incident on 21 May 1982, John Clearno tried to hijack a Philippine One-Eleven while on the ground, but was eventually overpowered by the cockpit crew following hours of negotiation. No passengers or crew were injured.<ref>[https://news.google.com/newspapers?id=wxYzAAAAIBAJ&sjid=XTIHAAAAIBAJ&pg=3929,2907368&dq=bac-111&hl=en "Airliner's Crew Overpowers Hijackers of Philippine Plane."] ''Lodi News-Sentinel'', 21 May 1982. p. 29.</ref> Philippine Airlines replaced the type with the Boeing 737 from 1989 onwards.<ref>Hill 1999, pp. 156-157.</ref>

Romania was a major customer for British-produced One-Elevens, with several large orders in the 1970s. These aircraft were often fitted with equipment such as engine '[[hush kit]]s'. In May 1977, a major cooperation agreement between British Aerospace and the Romanian government was signed, and this led to a gradual One-Eleven [[technology transfer]] to Romania. Full contracts for licence production under the Rombac name followed two years later. Complete airframes and components were provided to assist in the venture.<ref>Hill 1999, pp. 115-117.</ref> All Rombac One-Elevens manufactured by Romaero were delivered to [[TAROM]] and [[Romavia]], which leased them to airlines across both Eastern and Western Europe. Rombac-produced One-Elevens would be adopted by many emerging operators globally, including [[Lauda Air]] in Austria, and [[Aero Asia International]] in Pakistan.<ref>Hill 1999, pp. 118, 154-156.</ref> Two planes served as the private jets of Romanian communist leaders [[Nicolae Ceaușescu]] and [[Ion Iliescu]] during 1986 to 1989. Due to the planes are "extreme rarity and significance for the technical history of Romania," they were added to the “treasure” category of Romania’s mobile cultural heritage in 2021, not allowed to leave the country.<ref>{{Cite web|url= https://apnews.com/article/europe-romania-business-government-and-politics-f3b9e42d764553784d9b229cb30ee6d9|title= Romania-built plane used by Ceausescu going up for auction|date= May 19, 2021|work=The Associated Press}}</ref> Under the BAC licence, 9 planes were made in Romania. Some of them served in a small airline, LAR, its sole destination being Tel Aviv.<ref>{{Cite web|url= https://news.yahoo.com/plane-romanias-ex-dictators-fleet-214309868.html|title= Plane of Romania's ex-dictator's fleet sold at auction|work=AFP|date= May 27, 2021}}</ref>

One-Elevens remained in widespread use with European operators into the 1990s. Once retired from major operators, they were often sold to smaller airlines, often in the Far East and Africa. [[Nigeria]] was a major operator until the type was grounded after a crash in 2002. A major factor for the withdrawal from European service of remaining One-Elevens was the [[Joint Aviation Authorities|Stage III noise abatement regulations]], which came into effect from March 2003. Bringing the Rolls-Royce Spey engines into compliance with the noise regulations with [[hush kit]]s was expensive, and many European operators chose to dispose of the type from their fleets. In 2010, the [[European Aviation Safety Agency]] accepted an [[Airbus]] request to revoke the Type Certificate for the BAC One-Eleven. As a result, BAC One-Eleven aircraft registered in any [[Member state of the European Union|EU Member State]] are no longer eligible for a normal certificate of airworthiness. In December 2012, the last operational One-Eleven in the UK, which had continued to fly as a military aircraft, was retired.<ref>[http://www.qinetiq.com/news/pressreleases/Pages/QinetiQ-BAC-1-11-flies-into-history.aspx "QinetiQ BAC 1-11 flies into history."] {{webarchive|url=https://web.archive.org/web/20130625150725/http://www.qinetiq.com/news/pressreleases/Pages/QinetiQ-BAC-1-11-flies-into-history.aspx |date=25 June 2013 }} ''QinetiQ'', 29 April 2013.</ref> Eventually, on 7 May 2019, the last flyable One-Eleven was retired by [[Northrop Grumman]] after serving as an [[Lockheed Martin F-35 Lightning II|F-35]] testbed.
{{Clear}}

==Variants==
[[File:British Aerospace BAC One Eleven British Airways G-BBME, DUS Düsseldorf (Duesseldorf International), Germany PP1361872924.jpg|thumb|The initial variants are {{cvt|93.5|ft}} long to accommodate up to 89 seats with a single [[overwing exit]] per side.]]
[[File:British Caledonian BAC 111-509EW Gatwick.jpg|thumb|The later 500 series are {{cvt|107|ft}} long to accommodate up to 119 seats with two overwing exits.]]

;One-Eleven 200 :Initial production version, {{convert|10410|lbf|kN}} Spey Mk 506 engines.;<ref name="JAWA66 p138-9"/> individual customer designations within this series. 56 built.<ref name="Willis p66">Willis ''Air International'' October 2006, p. 66.</ref>
;One-Eleven 217 :Version for the RAAF using a 200 series fuselage with RR Spey Mk511-14 engines, low-pressure tyres, a navigator's station and a sextant hatch in the cockpit ceiling. Two built.<ref>{{Cite web|url=https://www.airforce.gov.au/sites/default/files/minisite/static/7522/RAAFmuseum/research/aircraft/series3/A12.htm|title = RAAF Museum: Royal Australian Air Force}}</ref>
;One-Eleven 300 :Uprated engines ({{convert|11400|lbf|kN}} Spey Mk 511s), more fuel for longer range;<ref name="JAWA66 p138-9"/> individual customer designations within this series. 9 built.<ref name="Willis p66"/>
;One-Eleven 400 :Series 300 with American instrumentation and equipment;<ref name="JAWA66 p138-9"/> individual customer designations within this series. 69 built.<ref name="Willis p66"/>
;One-Eleven 475 :Series 400 body with Series 500 wing and powerplant plus rough-airfield landing gear and body protection.<ref name="jawa76 p170-2"/> 6 built.
;One-Eleven 485GD: Similar to 475, 3 for [[Oman]].
;Rombac 1-11-495 :Planned Romanian-built version of the Series 475.<ref name="JAWA82 p173"/> None completed.<ref name="pilling p213-4"/>
;One-Eleven 500 :Extended body version with up to 119 seats and longer span wings. Fitted with more powerful engines ({{convert|12550|lbf|kN}} Spey 512s);<ref name="jawa76 p170-2" /> individual customer designations within this series. 86 built.<ref name="Willis p66"/>
;One-Eleven 510ED :Variant of the 500 series built for BEA/British Airways. Size and engines same as other 500s, cockpit modified to provide more commonality with [[Hawker Siddeley Trident|HS.121 Trident]] and required a different type rating from all other 500 series One-Elevens.
;Rombac 1-11-560 :Romanian-built version of the Series 500.<ref name="JAWA82 p173"/> Nine completed.<ref name="pilling p213-4"/>
;One-Eleven 670 :Series 475 with improved aerodynamics and reduced noise; one converted from Series 475.<ref name="AI jan79 p12,41">''Air International'' January 1979, pp. 12, 41.</ref><ref name="database p82">Chorlton ''Aeroplane'' November 2012, p. 82.</ref>
;VC-92:[[Brazilian Air Force]] designation of the One-Eleven 423ET.<ref>{{Cite web |title=Brazilian Military Aircraft Designations |url=https://designation-systems.net/non-us/brazil.html |access-date=2025-03-17 |website=designation-systems.net}}</ref>

==Operators==
[[File:British Aircraft Corporation BAC 1-11 Series 401AK, Northrop Grumman JP5644332.jpg|thumb|The last aircraft in service, used by [[Northrop Grumman]] as an airborne testbed, was retired in 2019.]]
{{Main|List of BAC One-Eleven operators}}

The BAC One-Eleven was widely used by civil and military operators.

After the One-Eleven's type certificate had been withdrawn, they flew as experimental aircraft in the research and development category.<ref>https://registry.faa.gov/aircraftinquiry/Search/NNumberResult?NNumbertxt=164W FAA entry for N164W</ref>

On 6 May 2019, the last aircraft still in service, used by [[Northrop Grumman]] as an airborne test bed for the [[F-35]] programme, was retired.

==Notable accidents and incidents==
===Accidents with fatalities===
* On 22 October 1963, a [[1963 BAC One-Eleven test crash|prototype aircraft crashed]] during a test flight, while testing stall conditions near [[Chicklade]] in [[Wiltshire]], England. All seven crew members were killed. This was not a production-model plane and this incident is described more fully in the [[BAC One-Eleven#Development|Development]] section above.
* On 6 August 1966, [[Braniff International Airways Flight 250]] disintegrated in mid-air after flying into a severe thunderstorm near [[Falls City, Nebraska]]. It was en route to [[Omaha, Nebraska]], from [[Kansas City, Missouri]]. Thirty-eight passengers and four crew members were killed in the crash. The plane was a BAC One-Eleven-203AE.<ref>[http://libraryonline.erau.edu/online-full-text/ntsb/aircraft-accident-reports/AAR68-AL.pdf "Braniff Airways, Inc. BAC 1-11, N1553, Near Falls City, Nebraska."] ''National Transportation Safety Board'', 18 April 1968.</ref>
* On 23 June 1967, a Mohawk Airlines One-Eleven-204AF while flying [[Mohawk Airlines Flight 40]] suffered a loss of pitch control following an on-board fire that caused heavy damage in the tail area. Flight 40 was a regularly scheduled passenger flight between [[Elmira, New York]] and [[Washington, DC]]. It crashed outside [[Blossburg, Pennsylvania]] with the loss of all 34 passengers and crew.<ref>{{usurped|[https://web.archive.org/web/20101201150810/http://www.airdisaster.com/reports/ntsb/AAR68-AG.pdf "Aircraft Accident Report: Mohawk Airlines, Inc. BAC 1-11, N1116J, Near Blossburg, Pennsylvania."]}} ''National Transportation Safety Board'', 18 April 1968.</ref> The fire was traced to the [[auxiliary power unit]] (APU); as a direct result of this accident in-flight use of the APU was banned.<ref>Sorlucco 2005, pp. 78-79.</ref>
* On 12 September 1969, a [[Philippine Airlines]] BAC One-Eleven registration PI-C1131 operating as [[Philippine Air Lines Flight 158|Flight 158]] en route from [[Mactan–Cebu International Airport]] in [[Cebu]] to [[Manila International Airport|Manila International Airport (now Ninoy Aquino Airport)]] in [[Manila]], Philippines struck a mango tree on the hill in suburban Kula-ike, [[Antipolo]], [[Rizal (province)|Rizal]], {{convert|12|nmi|km}} east of its destination while on a VOR approach to runway 24. There were 47 people on board, of which 45 were killed. One passenger and one flight steward survived, but both were hospitalized with burns. The crash was the worst air disaster in the Philippines involving commercial aircraft until [[Philippine Airlines Flight 206|1987]].<ref name=asn>{{Cite web|url=https://aviation-safety.net/database/record.php?id=19690912-0|title=ASN Aircraft accident BAC One-Eleven 402AP PI-C1131 Manila International Airport (MNL)|first=Harro|last=Ranter|website=aviation-safety.net}}</ref>
* On 7 December 1970, a TAROM One-Eleven 424EU flying from [[Tel Aviv]] to Bucharest crashed on approach to the [[Mihail Kogălniceanu International Airport]] after having been diverted from its original destination. The accident occurred due to deteriorating weather and 19 of the 24 occupants were killed.<ref>{{Cite web|url=http://aviation-safety.net/database/record.php?id=19701207-0 |title=Aviation Safety Network Accident Description |access-date=2015-12-01 |archive-url=https://web.archive.org/web/20151208115650/http://aviation-safety.net/database/record.php?id=19701207-0 |archive-date=2015-12-08 |url-status=live}}</ref>
* On 6 September 1971, a One-Eleven 515FB operating as [[Paninternational Flight 112]] collided with a bridge during an emergency landing on the [[Bundesautobahn 7|A7 Autobahn]] in [[Hamburg]], shearing off both wings after a double engine failure during takeoff. The [[Water injection (engine)|water injection]] system had inadvertently been filled with jet fuel instead of water. Twenty-two of the 121 people aboard died.<ref name="ASN">[http://aviation-safety.net/database/record.php?id=19710906-0 "ASN Aircraft accident BAC One-Eleven 515FB D-ALAR Hamburg-Fuhlsbüttel Airport."] ''Aviation Safety Network'', Retrieved: 23 October 2010.</ref>
* On 18 April 1974, [[Court Line Flight 95]], operated by One-Eleven 528 G-AXMJ was involved in a ground collision with [[Piper Aztec|Piper PA-23 Aztec]] G-AYDE at [[Luton Airport|London Luton Airport]] due to the Aztec entering the active runway without clearance. The pilot of the Aztec was killed and his passenger was injured. All 91 on board the One-Eleven safely left the aircraft after take-off was aborted.
* On 21 November 1977, [[Austral Líneas Aéreas Flight 9]] flying from [[Buenos Aires]] to [[Bariloche|San Carlos de Bariloche]], suffered pressurisation problems whilst climbing to 35,000 feet. Later on approach into [[San Carlos de Bariloche Airport|San Carlos de Bariloche International Airport]], the plane struck terrain and crashed. All five crew and 41 of 74 passengers were killed.<ref>{{Cite web |last=Ranter |first=Harro |title=ASN Aircraft accident BAC One-Eleven LV-JGY |url=https://asn.flightsafety.org/asndb/324122 |access-date=30 November 2022 |website=Aviation Safety Network}}</ref>
* On 7 May 1981, [[Austral Líneas Aéreas Flight 901]] crashed on approach into [[Jorge Newbery Airport]], [[Buenos Aires]], after a flight from [[San Miguel de Tucumán]]. The likely cause was the weather and [[pilot error]]. All 5 crew and 26 passengers were killed.<ref name=":0">{{Cite web |last=Ranter |first=Harro |date= |title=ASN Aircraft accident BAC One-Eleven 529FR LV-LOX Buenos Aires-Jorge Newbery Airport, BA (AEP) |url=https://aviation-safety.net/database/record.php?id=19810507-0 |url-status=live |archive-url=https://web.archive.org/web/20050421113212/http://www.aviation-safety.net:80/database/record.php?id=19810507-0 |archive-date=2005-04-21 |access-date=2020-05-10 |website=Aviation Safety Network |publisher=[[Flight Safety Foundation]]}}</ref>
* On 21 July 1989, [[Philippine Airlines Flight 124]] overran the runway when attempting a landing at [[Ninoy Aquino International Airport]], [[Manila]]. None of the 98 passengers on board were killed, but eight people on the ground died when the aircraft came to a stop on an adjacent highway.<ref>{{Cite web |title=ASN Aircraft accident BAC One-Eleven 516FP RP-C1193 Manila International Airport (MNL) |url=https://aviation-safety.net/database/record.php?id=19890721-1 |access-date=2024-02-24 |website=aviation-safety.net}}</ref><ref>{{Cite news |date=21 July 1989 |title=Philippine Jet Misses Runway, Kills 8 |url=https://news.google.com/newspapers?id=zpMUAAAAIBAJ&sjid=PYQDAAAAIBAJ&pg=3500,1923734&dq=bac-111&hl=en |access-date= |work=Deseret News |page=2}}</ref><ref>{{Cite web |title=Crash of a BAc 111-516FP in Manila: 9 killed {{!}} Bureau of Aircraft Accidents Archives |url=https://www.baaa-acro.com/crash/crash-bac-111-516fp-manila-9-killed |access-date=2024-02-24 |website=www.baaa-acro.com}}</ref>
* On 26 June 1991, {{Interlanguage link|1991 Okada Air BAC One-Eleven crash|lt=an Okada Air flight|de|Flugunfall einer BAC 1-11 der Okada Air bei Sokoto}} ran out of fuel while on approach to Sokoto Airport and crashed during a forced landing, killing four passengers.<ref>{{ASN accident|title=5N-AOW|id=19910626-0}}</ref>
* On 18 September 1994, [[1994 Oriental Airlines crash|an Oriental Airlines flight]] carrying Nigerian football team [[Heartland F.C.|Iwuanyanwu Nationale FC]] home from a CAF Champions League quarterfinals match in [[Tunis]] crashed on its fourth landing attempt at [[Tamanrasset Airport]]. Five people on board died, including three crew and two passengers, both footballers for the team.<ref>{{cite web |title=18 September 1994 |url=https://aviation-safety.net/database/record.php?id=19940918-0 |publisher=aviation-safety.net}}</ref><ref>{{cite web |date=16 September 2014 |title=Nigeria: Heartland Remembers 18 September Air Crash Victims |url=https://allafrica.com/stories/201409171143.html |publisher=allafrica.com}}</ref>
* On 29 July 1997, {{Interlanguage link|1997 ADC Airlines BAC One-Eleven crash|lt=an ADC Airlines flight|de|Flugunfall der ADC Airlines bei Calabar}} overshot the runway while landing at [[Margaret Ekpo International Airport|Calabar Airport]], killing one person.<ref>{{Cite web |last=Ranter |first=Harro |title=ASN Aircraft accident BAC One-Eleven 203AE 5N-BAA Calabar Airport (CBQ) |url=https://asn.flightsafety.org/asndb/324164 |access-date=2017-04-10 |website=Aviation Safety Network}}</ref>
* On 4 May 2002, [[EAS Airlines Flight 4226]] crashed in a suburb of [[Kano (city)|Kano]], [[Nigeria]], shortly after takeoff, killing 73 of the 77 people on board and 30 more on the ground. This remains the worst crash of a BAC One-Eleven, with a total of 103 deaths.<ref name = "3 April 2003">"Nigeria; EAS Kano Crash Report Indicts Pilot." ''Africa News'', 3 April 2003.</ref>

===Other incidents===
* On 9 July 1978, [[Allegheny Airlines]] Flight 453 crash-landed at [[Greater Rochester International Airport]] while arriving from [[Boston Logan International Airport]]. The aircraft was carrying 77 people. According to the NTSB report, the flight landed on Runway 28 at too high a speed, but with sufficient performance capability to reject the landing. The pilots chose to continue the landing, the aircraft skidded off the end of the runway, and its landing gear were sheared off by a ditch. There were no fatalities but the aircraft was written off.<ref>{{cite web | url = https://www.ntsb.gov/_layouts/ntsb.aviation/brief.aspx?ev_id=41686&key=0 | title = DCA78AA017 | website = ntsb.gov | publisher = National Transportation Safety Board | access-date=5 July 2020}}</ref>
* On 4 August 1984, a [[Philippine Airlines]] flight overshot runway 36 and ended up in the sea when attempting a landing at [[Daniel Z. Romualdez Airport]], [[Tacloban City]], Philippines. All 70 passengers and five crew survived.<ref>{{ASN accident|id=19840804-0|title=RP-C1182|accessdate= October 26, 2023}}</ref>
* On 10 June 1990, [[British Airways Flight 5390]]'s cockpit window blew out at altitude after incorrect bolts had been used to secure it. Captain Tim Lancaster was blown half out of the cockpit by the pressure differential; members of the cabin crew clung to his legs to keep him from being blown out of the aircraft. The plane made an emergency landing at [[Southampton Airport]]. The pilot survived, as did all the crew and passengers.<ref>[http://www.smh.com.au/news/World/This-is-your-captain-screaming/2005/02/04/1107476802601.html "This is your Captain Screaming."] ''The Sydney Morning Herald'', 5 February 2005.</ref><ref>[https://www.gov.uk/aaib-reports/bac-one-eleven-528fl-g-bjrt-10-june-1990 "Report on the Accident to BAC One-Eleven, G-BJRT over Didcot, Oxfordshire on 10 June 1990."] ''Air Accidents Investigation Branch'', 1992. p. 38.</ref> An investigation revealed that the shift maintenance manager had used incorrect bolts as they were similar to the bolts which had been previously used on the aircraft; he replaced them at a like for like ratio. 84 of the 90 bolts used to secure the window were too small in diameter, whilst the remaining six were too short in length.

== Aircraft on display ==
[[File:BAC 111-510ED 'G-AVMU' (24980480106).jpg|thumb|One-Eleven 510ED ''County of Dorset'' on display at the [[Imperial War Museum Duxford]]]]

* One-Eleven 475AM G-ASYD at the Brooklands Museum, Surrey, United Kingdom.<ref name="WR23-211">Ellis 2012, p. 211</ref>
* One-Eleven 510ED G-AVMU at the [[Imperial War Museum Duxford]], Cambridgeshire, United Kingdom.<ref name="WR23-23">Ellis 2012, p. 23</ref>
* One-Eleven 510ED G-AVMO at the [[National Museum of Flight]], East Fortune, Scotland, United Kingdom.<ref name="WR23-286">Ellis 2012, p. 286</ref>
* One-Elevens CC-CYL and CC-CYM at the [[Museo Nacional Aeronáutico y del Espacio]] in Santiago, Chile.<ref>{{cite web|url=http://www.museoaeronautico.gob.cl/home/colecciones/aeronaves|title=Aeronaves|work=museoaeronautico.gob.cl|access-date=12 June 2016|archive-date=3 January 2018|archive-url=https://web.archive.org/web/20180103075003/http://www.museoaeronautico.gob.cl/home/colecciones/aeronaves|url-status=dead}}</ref>
* One-Eleven LV-MRZ in San Justo Shopping, Buenos Aires, Argentina with DC-9 tail<ref>{{cite web|title=Un Bac One Eleven en San Justo pero no en un 100 % - Aviones en Argentina |date=4 November 2021 |url=https://avionesenargentina.com/un-bac-one-eleven-en-san-justo-pero-no-en-un-100__trashed}}</ref>
* One-Eleven 510ED G-AVMN at the Panzemuseum East, [[Slagelse]], [[Denmark]]. former [[AB Airlines]].<ref name="bsc111">{{Cite web|url=http://www.bac1-11jet.co.uk/bac1-11jet.co.uk%20News.htm|title=NEWS|accessdate=8 May 2023}}</ref>
* A former [[US Air]] BAC One-Eleven, registration N1117J, is located near [[Orlando International Airport]], and is used for firefighting exercises. The aircraft is a mostly empty shell and is in poor condition.
* A former MOD(PE) (later QinetiQ) BAC One-Eleven 539GL serial ZH763 is located at the Cornwall Aviation Heritage Centre in Newquay, Cornwall.<ref name="bsc111" /> On 25 November 2023 the fuselage was moved to the exterior of [[Solent Sky]] museum.<ref name=timothyBAC>{{cite news |last=Edgley |first=Timothy |date=26 November 2023 |title=Aircraft towed through Southampton streets on way to Solent Sky Museum |url=https://www.dailyecho.co.uk/news/23948275.aircraft-towed-southampton-streets-way-solent-sky-museum/ |work=Southern Daily echo}}</ref><ref>{{cite web|title=Aircraft pulled through streets of Southampton|url=https://www.bbc.co.uk/news/av/uk-england-hampshire-67531284|work=BBC News|date=2023-11-25}}</ref>
* Two Rombac One-Eleven 560 (YR-BRE and the last built, YR-BRI) are stored at Bucharest [[Henri Coandă International Airport]]. The two aircraft were classified in Romania's national cultural heritage ({{ill|Patrimoniul cultural național al României|ro}}) on 11 February 2021.<ref>{{Cite web|url=https://adevarul.ro/locale/alba-iulia/doua-bijuterii-aeriene-construite-vremea-ceausescu-clasate-patrimoniul-national-intampla-aeronavele-rombac-1_603fbca45163ec4271897dbb/index.html|title=Două bijuterii aeriene construite pe vremea lui Ceauşescu, clasate în patrimoniul naţional. Ce se va întâmpla cu aeronavele ROMBAC|work=[[Adevărul]]|author=Dorin Țimonea|date=4 March 2021|language=ro}}</ref><ref>{{cite web|url=https://boardingpass.ro/cele-doua-rombac-uri-1-11-au-fost-vandute-la-licitatie-pentru-285-de-mii-de-euro/|title=Cele două ROMBAC-uri 1-11 au fost vândute la licitație pentru 285 de mii de euro|language=ro|author=Gabriel Bobon|date=28 May 2021|work=BoardingPass.ro}}</ref>
* BAC One-Eleven TZ-BSC owned by Romaero was restored and exhibited at the Bucharest International Air Show (BIAS) and {{ill|Black Sea Defense & Aerospace|ro}} (BSDA) 2018.<ref>{{cite web|url=https://aeronewsglobal.com/a-doua-tinerete-un-bac-1-11-restaurat-de-romaero-poate-fi-admirat-la-bsda-si-bias-2018/|title=A doua tinerete: un BAC 1-11 restaurat de ROMAERO poate fi admirat la BSDA si BIAS 2018|language=ro|author=Teodor Stefan|date=15 May 2018|website=aeronews.ro}}</ref>
* A former [[Aero America]] BAC One-Eleven, registration N111RZ, is located at the premises of the Indian Hills Equestrian Centre, Illinois. The aircraft is missing its port side wing. Last flown by Rotec.<ref>{{Cite web|url=http://www.aerialvisuals.ca/AirframeDossier.php?Serial=154504|title=Aerovisuals airframe dossier|website=aerialvisuals.ca}}</ref>
* 215AU, registration SX-BAR was transferred from former Athens Airport to Lavrio. Last flown by Hellenic Airforce.
* A BAC One-Eleven Cockpit is on display and accessible at Malta Aviation Museum <ref>{{cite web|url=https://www.maltaaviationmuseum.com/|title=Malta Aviation Museum}}</ref>
* A complete BAC One-Eleven is on display in Topeka, KS at the American Flight Museum, tail number N789CF

==Specifications==
{{Overly detailed|section|nosplit=1|details=per [[WP:AIRMOS]], this section should cover the specifications of only a single variant|date=June 2025}}
[[File:Main cabin of BAC One-Eleven 510ED ‘G-AVMO’ (25913063348).jpg|thumb|Five-abreast cabin, [[National Museum of Flight]]]]

{| style="text-align: center" class="wikitable"
!Model
! 200<ref name="JAWA66 p138-9">Taylor, John W. R. ''Jane's All The World's Aircraft 1966–67''. London: Sampson Low, Marston & Company, 1966, pp. 138–139.</ref>
! 300/400<ref name="JAWA66 p138-9"/>
! 475<ref name="jawa76 p170-2">[[John W. R. Taylor|Taylor, John W. R.]] ''Jane's All The World's Aircraft 1976–77''. London: Jane's Yearbooks, 1976. {{ISBN|0-354-00538-3}}, pp. 170–172.</ref>
! 500<ref name="jawa76 p170-2"/>
|-
! Cockpit crew
| colspan=4 | 2
|-
! Seating limit<ref>{{Cite web |url=http://rgl.faa.gov/Regulatory_and_Guidance_Library/rgMakeModel.nsf/0/6a88d59e4baffc4186257904006274b8/$FILE/A5EU%20Rev%2029.pdf |title=FAA Type Certificate Data Sheet |access-date=15 April 2016 |archive-date=30 May 2020 |archive-url=https://web.archive.org/web/20200530121559/https://rgl.faa.gov/Regulatory_and_Guidance_Library/rgMakeModel.nsf/0/6a88d59e4baffc4186257904006274b8/$FILE/A5EU%20Rev%2029.pdf |url-status=dead }}</ref>
| colspan=3 | 89
| 119
|-
! Length
| colspan=3 | {{cvt|93|ft|6|in|m}}
| colspan=1 | {{cvt|107|ft|0|in|m}}
|-
! Wing Area
| colspan=2 | {{cvt|88|ft|6|in|m}} span, {{cvt|980|sqft|sqm}} area
| colspan=2 | {{cvt|93|ft|6|in|m}} span, {{cvt|1031|sqft|sqm}} area
|-
! Height
| colspan=4 | {{cvt|24|ft|6|in|m}}
|-
! Cabin Width
| colspan=4 | {{cvt|126|in|m|2}}
|-
! Cabin length
| colspan=2 | {{cvt|50|ft|0|in|m}}
| {{cvt|56|ft|10|in|m}}
| {{cvt|70|ft|4|in|m}}
|-
! Empty weight
| {{cvt|46312|lb|kg}}
| {{cvt|48722|lb|kg}}
| {{cvt|51731|lb|kg}}
| {{cvt|54582|lb|kg}}
|-
! [[MTOW]]
| {{cvt|78500|lb|kg}}
| {{cvt|87000|lb|kg}}
| {{cvt|98500|lb|kg}}
| {{cvt|104500|lb|kg}}
|-
! Max. payload
| {{cvt|17688|lb|kg}}
| {{cvt|22278|lb|kg}}
| {{cvt|21269|lb|kg}}
| {{cvt|26418|lb|kg}}
|-
! Engines (x2)
| [[Rolls-Royce Spey]] Mk 506
| Mk 511
| colspan=2 | Mk 512-14DW
|-
! Thrust (2x)
| {{cvt|10410|lbf|kN}}
| {{cvt|11400|lbf|kN}}
| colspan=2 | {{cvt|12550|lbf|kN}}
|-
! Max. cruise
| colspan=2 | {{cvt|548|mph|kn km/h|disp=out}}
| colspan=2 | {{cvt|541|mph|kn km/h|disp=out}}
|-
! Ceiling
| colspan=4 | {{cvt|35000|ft|m}}
|-
! Climb rate
| {{cvt|2750|ft/min|m/s}}
| {{cvt|2450|ft/min|m/s}}
| {{cvt|2480|ft/min|m/s}}
| {{cvt|2280|ft/min|m/s}}
|-
! Takeoff (MTOW)
| {{cvt|6250|ft|m}}
| {{cvt|6700|ft|m}}
| {{cvt|5500|ft|m}}
| {{cvt|6500|ft|m}}
|-
! Range{{efn|Typical payload, 2 hr reserve}}
| {{cvt|830|mi|nmi km|disp=out}}
| {{cvt|1270|mi|nmi km|disp=out}}
| {{cvt|1865|mi|nmi km|disp=out}}
| {{cvt|1705|mi|nmi km|disp=out}}
|}
{{Notelist}}

==See also==
{{Portal|UK|Aviation}}
{{aircontent
|related=
|similar aircraft=
* [[Boeing 737]]
* [[Dassault Mercure]]
* [[Fokker F28 Fellowship]]
* [[McDonnell Douglas DC-9]]
* [[Sud Aviation Caravelle]]
* [[Tupolev Tu-134]]
* [[Yakovlev Yak-42]]
|see also=
|lists=
}}

==References==

===Citations===
{{Reflist}}

===Bibliography===
{{refbegin}}
* Chorlton, Martyn. "Database: British Aircraft Corporation One-Eleven". ''[[Aeroplane Monthly|Aeroplane]]'', Vol. 40 No. 11, November 2012. pp.&nbsp;67–82. {{ISSN|0143-7240}}.
* Ellis, Ken. ''Wreck & Relics 23rd Edition''. Manchester, England:Crecy Publishing, 2012. {{ISBN|978-0-859-79172-4}}.
* Hill, Michael. ''BAC One-Eleven''. Crowood Press, 1999. {{ISBN|1-86126-219-1}}.
* Lewis, Walter David. ''Airline Executives and Federal Regulation: Case Studies in American Enterprise from the Airmail Era to the Dawn of the Jet Age''. Ohio State University Press, 2000. {{ISBN|0-8142-0833-9}}.
* "One-Eleven for the 'Eighties". ''Air International'', Vol. 16 No. 1, January 1980. pp.&nbsp;7–12, 41–42.
* Payne, Richard. "X Marks the Spot". ''[[Aeroplane Monthly|Aeroplane]]'', Vol. 49, No. 2, February 2021. pp.&nbsp;36–41. {{ISSN|0143-7240}}.
* Sorlucco, Jerry. ''A Good Stick: An Airline Captain Lives the History of 20th Century Commercial Aviation.'' AuthorHouse, 2005. {{ISBN|1-4208-4843-7}}.
* {{cite book |last= Spooner |first= Nigel |year= 2024 |title= A History of Aviation at Brooklands in 100 Objects |location= Barnsley, England |publisher= Pen & Sword Airworld |isbn= 978-1-52679-091-0}}.
* [[John W. R. Taylor|Taylor, John W. R.]] (ed.) ''Jane's All the World's Aircraft 1975–76''. London: Jane's Yearbooks, {{ISBN|0-354-00521-9}}.
* Willis, Dave. "Aircraft Profile: BAC One-Eleven". ''Air International'', Vol. 70 No. 4. October 2006. pp.&nbsp;64–66. {{ISSN|0306-5634}}.
{{refend}}

==Further reading==
{{Commons and category|BAC 1-11}}
* [http://www.britishpathe.com/video/bac-111-production-colour British Pathé report on BAC 1-11 production in 1965]
* Skinner, Stephen. ''The Long and the Short of It: The Story of a Great British Airliner Prototype, BAC One-Eleven G-ASYD''. ''[[Air Enthusiast]]'' 105, May/June 2003, pp.&nbsp;44–51. {{ISSN|0143-5450}}
* [https://www.forbes.com/sites/matthewstibbe/2011/09/17/inside-a-retro-bac-1-11-business-jet/ "Inside a Retro BAC 1-11 Business Jet"]. ''Forbes'', 17 September 2011
* [https://www.baesystems.com/en/heritage/bac1-11 "BAC 1-11"]. BAE Systems
* {{cite book |author1=Key Publishing |title=BAC One-Eleven |series=Historic Commercial Aircraft Series, Vol 9 |date=2023 |publisher=Key Publishing |location=Stamford, Lincs, UK |isbn=9781802823677 |url={{GBurl|lZJBzwEACAAJ}}}}

{{British Aircraft Corporation aircraft}}
{{BAE aircraft}}
{{FAB aircraft designations}}

{{Authority control}}

{{DEFAULTSORT:Bac One-Eleven}}
[[Category:BAC One-Eleven| ]]
[[Category:Aircraft first flown in 1963]]
[[Category:British Aircraft Corporation aircraft|One-Eleven]]
[[Category:1960s British airliners]]
[[Category:Low-wing aircraft]]
[[Category:Twinjets]]
[[Category:T-tail aircraft]]
[[Category:Aircraft with retractable tricycle landing gear]]