The Airbus A340 is a long-range four-engined wide-body commercial passenger jet airliner. Developed by Airbus Industrie, a consortium of European aerospace companies, which is now fully-owned by EADS, the A340 is manufactured at Toulouse, France. It seats up to 375 passengers in the standard variants and 440 in the stretched −600 series. Depending on the model, it has a range of between 6,700 to 9,000 nautical miles (12,400 to 17,000 km). It is similar in design to the twin-engined A330 with which it was concurrently designed. Its distinguishing features are four high-bypass turbofan engines and three-bogie main landing gear.
Airbus manufactured the A340 in four fuselage lengths. The initial variant, A340-300, entered service in 1993, measured 59.39 metres (194.8 ft), followed by the shorter −200; the stretched A340-600 was a 15.91 metres (52.2 ft) stretch of −200. This particular variant was developed alongside the shorter A340-500, which would become the longest-ranged commercial airliner until the arrival of the Boeing 777-200LR. The two initial models were powered by the CFM56-5C, rated at 151 kilonewtons (34,000 lbf), while Rolls-Royce held exclusive powerplant rights to the extended-ranged and heavier −500 and −600 models, through the 267-kilonewton (60,000 lbf) Rolls-Royce Trent 500. Initial A340 versions share the fuselage and wing of the A330 while the −500/-600 models are longer and have larger wings.
Launch customers Lufthansa and Air France placed the A340 into service in March 1993. As of March 2011, 379 orders have been placed (not including private operators), of which 375 have been delivered, with a backlog of four aircraft. The most common type were the A340-300 model, with 218 aircraft delivered. Lufthansa is the biggest operator of the A340, having acquired 59 aircraft. The A340 is used on long-haul, trans-oceanic routes due to its immunity from ETOPS; however, with reliability in engines improving, airlines are progressively phasing out the type in favour of more economical twinjets such as the Boeing 777.
In 1982, the first specifications of the TA9 and TA11 were released. While the TA9 had a range of 3,300 nautical miles (6,100 km), the TA11 range was up to 6,830 nautical miles (12,650 km). At the same time, Airbus also sketched the TA12, twin-engine derivative of the TA11, which was optimised for flights with 2,000 nautical miles (3,700 km) less range.
When Airbus designed the Airbus A300 during the 1970s, it envisioned a broad family of airliners to compete against Boeing and Douglas, two established US aerospace manufacturers. From the moment of formation, Airbus had begun studies into derivatives of the Airbus A300B in support of this long term goal. Prior to the service introduction of the first Airbus airliners, engineers within Airbus had identified nine possible variations of the A300 known as A300B1 to B9. A 10th variation, conceived in 1973, later the first to be constructed, was designated the A300B10. It was a smaller aircraft which would be developed into the long-range Airbus A310. Airbus then focused its efforts on the single-aisle market, coming up with the revolutionary family of airliners, later to be known as the Airbus A320, which was the first digital fly-by-wire commercial aircraft. The decision to work on the A320, instead of a four-engine aircraft proposed by the Germans, created divisions within Airbus. As the SA or "single aisle" studies (which later became the successful Airbus A320) underwent development to challenge the successful Boeing 737 and Douglas DC-9 in the single-aisle, narrow-body airliner market, Airbus turned its focus back to the wide-body aircraft market.
The A300B11, a derivative of the A310, was designed upon the availability of "ten ton" engines. It would seat between 180 to 200 passengers, and has a range of 6,000 nautical miles (11,000 km). It was deemed the replacement for the less-efficient Boeing 707s and Douglas DC-8 still in service.
The A300B11 was joined by another design, the A300B9, which was a larger derivative of the A300. The B9 was developed by Airbus from the early 1970s at a slow pace until the early 1980s. It was essentially a stretched A300 with the same wing, coupled with the most powerful turbofan engine at the time. It was targeted at the growing demand for high-capacity, medium-range, transcontinental trunk routes. The B9 would offer the same range and payload as the McDonnell Douglas DC-10, but would use between 25% to 38% less fuel. The B9 was therefore considered the replacement for the DC-10, and Lockheed L-1011 Tristar. To differentiate the programme from the SA studies, the B9 and B11 were redesignated the TA9 and TA11 (TA standing for "twin aisle"), respectively. In an effort to save development costs, the decision was made for the two to share the same wing and airframe; the projected savings were estimated at US$500 million (about £490 million or €495 million). The adoption of a common wing structure also had one technical advantage, the TA11's outboard engines could counteract the weight of the longer-range model by providing bending relief. Another factor was the split preference of those within Airbus and, more importantly, prospective airliner customers.
By the Paris Air Show in June 1985, more refinements were made to the TA9 and TA11, including the adoption of the A320 flight deck, fly-by-wire (FBW) flight control system and side-stick control. The adoption of a common cockpit design across the new Airbus series allowed operators to make significant cost savings; flight crews would be able to transition from one to another with only a week's training necessary. The TA11 and TA12 would use the front and rear fuselage sections of the A310. Components across the aircraft were modular, and exchangeable with other Airbus aircraft where possible. Airbus briefly considered a variable camber wing; the concept was that the wing could change its profile to produce the optimum shape for a given phase of flight. Studies were carried out by British Aerospace (BAe) at Hatfield and Bristol. Airbus estimated this would yield a 2% improvement in aerodynamic efficiency. The plan was later abandoned on the grounds of cost and difficulty of development.
On 27 January 1986, the Airbus Industrie Supervisory Board held a meeting in Munich, West Germany, after which the board chairman, Franz Josef Strauß, released a statement which said, "Airbus Industrie is now in a position to finalise the detailed technical definition of the TA9, which is now officially designated the A330, and the TA11, now called the A340, with potential launch customer airlines, and to discuss with them the terms and conditions for launch commitments". The designations were originally reversed because the airlines believed it illogical for a two-engine jet airliner to have a "4" in its name, while a quad-jet would not. Then on 12 May, Airbus sent new sale proposals to five prospective airlines including Lufthansa and Swissair.
In preparations for production of the A330/A340, Airbus's partners invested heavily in new facilities. Filton was the site of BAe's £7 million investment in a three-storey technical centre with an extra 15,000 square metres (160,000 sq ft) of floor area. BAe also spent £5 million expanding the Chester wing production plant by 14,000 m2 (150,000 sq ft) to accommodate a new production line. However, France saw the biggest changes with Aérospatiale starting construction of a new Fr.2.5 billion ($411 million) assembly plant, adjacent to Toulouse-Blagnac Airport, in Colomiers. By November 1988, the first 21 m (69 ft) pillars were erected for the new Clément Ader assembly hall. The assembly process, meanwhile, would feature increased automation with holes for the wing-fuselage mating process drilled by eight robots. The use of automation for this particular process saved Airbus 20% on labour costs and 5% on time.
British Aerospace accepted £450 million funding from the UK government, although it was well short of the £750 million originally requested. Funds from the French and German governments followed thereafter. Airbus also issued subcontracts to companies in Austria, Australia, Canada, China, Greece, Italy, India, Japan, South Korea, Portugal, the United States of America, and the former Yugoslavia. The A330 and A340 programmes were jointly launched on 5 June 1987, just prior to the Paris Air Show. The order book then stood at 130 aircraft from 10 customers, apart from the above-mentioned Lufthansa and International Lease Finance Corporation (ILFC). Eighty-nine of the total orders were A340 models. Over at McDonnell Douglas, ongoing tests of the MD-11 revealed a significant shortfall in the aircraft's performance. An important prospective carrier, Singapore Airlines (SIA), required a fully-laden aircraft that could fly from Singapore to Paris, against strong headwinds during mid-winter in the northern hemisphere. The MD-11, according to test results, would experience fuel starvation over the Balkans. Due to the less-than-expected performance figures, SIA cancelled its 20-aircraft MD-11 order on 2 August 1991, and ordered 20 A340-300s instead.
The first flight of the A340 occurred on 21 October 1991, marking the start of a 2,000-hour test flight programme involving six aircraft. From the start, engineers noticed that the wings were not strong enough to carry the outboard engines at cruising speed without warping and fluttering. To alleviate this, an underwing bulge called a plastron was developed to correct airflow problems around the engine pylons and to add stiffness. European JAA certification was obtained on 22 December 1992; FAA followed on 27 May 1993.
The A340-200 entered service in 1993 with launch customer Lufthansa, followed shortly thereafter by the −300 of Air France and the A330. Lufthansa's first A340, dubbed Nuernberg (D-AIBA), began revenue service on 15 March 1993. With the introduction of higher gross weight Boeing 777s, such as the -200ER and specifically -300ER, sales of the A340 began to decline. Over the last few years the 777 has outsold the A340 by a wide margin. Although the larger GE90 engines on the 777-300ER burn considerably more fuel than the Trent 500s, using only two of them compared to four Trents has meant a typical operating cost advantage of around 8–9%.
In January 2006, Airbus announced plans to develop the A340E (Enhanced). Airbus promoted that the A340E would be more fuel-efficient than earlier A340s and close the 8–9% disparity with the Boeing 777 by using Trent 1500 engines. Airbus has predicted that it will probably produce 127 A340 units through 2016, after which production will cease.
In mid-2008, jet fuel prices doubled compared to the year before; consequently, the A340's fuel consumption led airlines to curtail very long flights of greater than 15 hours. Thai Airways International cancelled its 17-hour, nonstop Bangkok–New York/JFK route on 1 July 2008. All four of its A340-500 fleet are for sale. While short flights stress aircraft more than long flights and result in more frequent fuel-thirsty take-offs and landings, ultra-long flights require an airline to fill an aircraft's fuel tanks to the maximum; this means that, en route, the plane is burning a lot of fuel just to carry fuel, a "flying tanker with a few people on board," Air France-KLM SA's chief executive Pierre-Henri Gourgeon told the Wall Street Journal.
While Thai Airways has consistently filled 80% of the seats on its New York City–Bangkok flights, it estimates that, at 2008 fuel prices, it would need an impossible 120% of seats filled just to break even. Other airlines are re-examining long-haul flights. In August 2008, Cathay Pacific told the Wall Street Journal that rising fuel prices are hurting its trans-Pacific long-haul routes disproportionately; it will cut the number of such flights it offers and redeploy its aircraft to shorter routes such as between Hong Kong and Australia. "We will...reshaping our network where necessary to ensure we fly aircraft to where we can cover our costs and also make some money," Cathay Pacific CEO Tony Tyler told the newspaper.
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