DevelopmentThe Airbus A321 was the first derivative of the A320, also known as the ''Stretched A320'', ''A320-500'' and ''A325''. Its launch came on 24 November 1988, around the same time as the A320 entered service, after commitments for 183 aircraft from 10 customers were secured. The of the Airbus A321 came on 11 March 1993, when the , registration F-WWIA, flew with IAE V2500 engines; the second prototype, equipped with CFM56-5B turbofans, flew in May 1993. Lufthansa and were the first to order the stretched Airbuses, with 20 and 40 aircraft requested, respectively. The first of Lufthansa's V2500-A5-powered A321s arrived on 27 January 1994, while Alitalia received its first CFM56-5B-powered aircraft on 22 March 1994. The A321-100 entered service in January 1994 with Lufthansa. Final assembly for the A321 was carried out in Germany (then West Germany), a first for any Airbus. This came after a dispute between the French, who claimed that the move would incur $150 million (€135 million) in unnecessary expenditure associated with the new plant, and the Germans, who claimed that it would be more productive for Airbus in the long run. The second production line was located in , which later produced the smaller and A318. For the first time, Airbus entered the , through which it raised $480 million (€475 million) to finance development costs. An additional $180 million (€175 million) was borrowed from and private investors. The A321 is the largest variant of the A320 family. The A321-200's length exceeds 44.5m, increasing maximum takeoff weight to . Wingspan remained unchanged, supplementing various wingtip devices. Two suppliers provided turbofan engines for the A321: CFM International with its CFM International CFM56, CFM56 and International Aero Engines with the IAE V2500, V2500 engine, both in the thrust range of . Over 30 years since launch, the A321 Maximum takeoff weight (MTOW) grew by 20% from the 83t -100 until the 101t A321XLR, seating is 10% more dense with 244 seats, up by 24, and range doubled from 2,300 nmi to 4,700 nmi. By 2019, 4,200 have been ordered—one-quarter of all Airbus single-aisles—including 2,400 neos, one-third of all A320neo orders.
DesignThe Airbus A321 is a narrow-body (single-aisle) aircraft with a retractable tricycle landing gear and is powered by two wing pylon-mounted turbofan engines. It is a low-wing cantilever monoplane with a conventional Empennage, tail unit having a single vertical stabilizer and rudder. Changes from the A320 include a fuselage stretch and some modifications to the wing. The fuselage was lengthened by a plug ahead of the wing and a plug behind it, so that the A321 is longer than the A320. The length increase required the overwing window exits of the A320 to be converted into door exits and repositioned in front of and behind the wings. To maintain performance, Flap (aircraft), double-slotted flaps and minor trailing edge modifications were included, increasing the wing area from to . The centre fuselage and Landing gear, undercarriage were reinforced to accommodate the increase in maximum takeoff weight of , taking it to .
A321-100The original derivative of the A321, the A321-100, had a shorter range compared to the A320 as extra fuel tankage was not added to the initial design to compensate for the extra weight. The MTOW of the A321-100 is . The A321-100 entered service with Lufthansa in 1994. Only about 90 were produced.
A321-200Airbus launched the heavier and longer-range A321-200 development in 1995 which has a full-passenger transcontinental US range. This is achieved through higher thrust engines (V2533-A5 or CFM56-5B3), minor structural strengthening, and an increase in fuel capacity with the installation of one or two optional tanks in the rear underfloor hold. The additional fuel tankage increases the total capacity of this model to . These modifications also increased the maximum takeoff weight of the A321-200 to . This variant first flew in December 1996, and entered service with Monarch Airlines in April 1997. Its direct competitors include the Boeing 757, 757-200 and the Boeing 737, 737-900/900ER.
A321neoOn 1 December 2010, Airbus launched the A320neo family (''neo'' for ''re-engine, New Engine Option'') with more range and 15% better fuel efficiency thanks to new CFM International LEAP-1A or Pratt & Whitney PW1000G engines and large sharklets. The lengthened A321neo prototype made its first flight on 9 February 2016. It received its type certification on 15 December 2016. The first entered service in May 2017 with Virgin America.
A321LRIn October 2014, Airbus started marketing a longer range maximum takeoff weight variant with three auxiliary fuel tanks with more operational range than a Boeing 757-200. Airbus launched the A321LR (Long Range) on 13 January 2015 with a range of with 206 seats in two classes. On 31 January 2018, it completed its first flight. Airbus announced its certification on 2 October 2018. On 13 November 2018, Arkia received the first A321LR.
A321XLRIn January 2018, Airbus was studying an A321LR variant with a further increased MTOW. The proposed A321XLR with a range extended to would be launched in 2019 to enter service in 2021 or 2022 to compete with the Boeing New Midsize Airplane, Boeing NMA. In November, Airbus indicated that the A321XLR would have an MTOW over and more range than the A321LR. The Airbus A321XLR, A321XLR was launched at the June 2019 Paris Air Show, with 4,700 nmi of range from 2023, including a new permanent Rear Centre Tank (RCT) for more fuel, a strengthened landing gear for a MTOW; and an optimised wing trailing-edge flap configuration to preserve take-off performance.
OperatorsAs of 29 February 2020, 2,038 Airbus A321 aircraft were in service with more than 100 operators. and China Southern Airlines operate the largest A321 fleets of 248 and 127 aircraft respectively.
Orders and deliveries''Data through end of February 2021''
Accidents and incidentsFor the Airbus A321, 32 aviation accidents and incidents have occurred, including 6 hull loss, hull-loss accidents or criminal occurrences with a total of 377 fatalities as of August 2019.