Differences include four 151 kN (34,000 lbf) CFM56s instead of two high-thrust turbofans to bypass ETOPS restrictions on trans-oceanic routes, and a three-leg main landing gear instead of two for a heavier 276 t (608,000 lb) Maximum Takeoff Weight (MTOW).

[11] 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.

[15] Adopting a common cockpit across the new Airbus series allowed operators to make significant cost savings; flight crews would be able to transition from one to another after one week of training.

On 27 January 1986, the Airbus Industrie Supervisory Board held a meeting in Munich, West Germany, after which board-chairman Franz Josef Strauß released a statement, 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.

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.

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.

Airbus also issued subcontracts to companies in Austria, Australia, Canada, China, Greece, Italy, India, Japan, South Korea, Portugal, the United States, and Yugoslavia.

[49] Unwilling to commit to a $1 billion development without good return on investment prospects and a second application, in 1997 GE Aviation stopped exclusivity talks for GE90 scaled down to 245–290 kN (55–65,000 lbf), leaving Rolls-Royce proposing a more cost-effective Rolls-Royce Trent variant needing less development and Pratt & Whitney suggesting a PW2000 advanced ducted propulsor, a PW4000 derivative or a new geared turbofan.

[61] The decision to terminate the program came as A340-500/600 orders came to a halt, with analyst Nick Cunningham pointing out that the A340 "was too heavy and there was a big fuel burn gap between the A340 and Boeing's 777 [specifically the A340-600 against the 777-300]".

Bertrand Grabowski, managing director of DVB Bank, noted, "in an environment where the fuel price is high, the A340 has had no chance to compete against similar twin engines, and the current lease rates and values of this aircraft reflect the deep resistance of any airlines to continue operating it".

[54][55][56] As a sales incentive amid low customer demand during the Great Recession, Airbus had offered buy-back guarantees to airlines that chose to procure the A340.

By 2013, the resale value of an A340 declined by 30% over ten years, and both Airbus and Rolls-Royce were incurring related charges amounting to hundreds of millions of euros.

[63] In 2013, as the ultra-long range market is a niche, the A340 was less attractive, with the best usage on long, thin routes from hot-and-high airports or as interim air charter.

[68] It was developed with technology from earlier Airbus aircraft and their features, like the A320 glass cockpit; it shares many components with the A330, notably identical fly-by-wire control systems and similar wings.

In 2008, Airbus launched a dedicated corporate jetliner version of the A340-200: one key selling point of this aircraft was a range of up to 8,000 nautical miles (15,000 km).

In August 2008, Cathay Pacific issued a declaration expressing concern over the adverse impact of escalating fuel expenses on its trans-Pacific long-haul routes, emphasizing a disproportionate burden on these particular flights.

Consequently, the airline outlined its strategic decision to curtail the frequency of such flights and reallocate its fleet to cater to shorter routes, notably those connecting Hong Kong and Australia.

The company's primary objective, as articulated by the airline's CEO Tony Tyler, entailed a comprehensive network restructuring aimed at optimizing operational efficiency by ensuring flights were directed to destinations that would yield cost coverage and financial gain simultaneously.

[97] Aviation Week noted that rapid performance increases of twin-engine aircraft has led to the detriment of four-engine types of comparable capacity such as the A340 and 747; at this point most 747s had accumulated significant flying hours before retirement in contrast to A340s which were relatively young when grounded.

Emirates Airlines decided to accelerate the retirement of its A340 fleet, writing down the value of the A340-500 type to zero despite the oldest −500 only being 10 years old, with president Tim Clark saying they were "designed in the late 1990s with fuel at $25–30.

The IAG overhaul featured improved conditions and furnishings in the business and economy classes; the business-class capacity was raised slightly while not changing the type's overall operating cost.

[103][104] In January 2021, Lufthansa, which was the largest remaining operator by then, announced that their entire Airbus A340-600 fleet will be retired with immediate effect and not return to service in the wake of the COVID-19 pandemic.

Due to its large wingspan, four engines, low capacity and general inferiority to the larger and more improved A340-300, the −200 proved very unpopular with mainstream airlines.

One version of this type (referred to by Airbus as the A340-8000) was ordered by the prince Jefri Bolkiah, with the request for a non-stop range of 15,000 kilometres (8,100 nmi; 9,300 mi).

This A340-8000, in the Royal Brunei Airlines livery had an increased fuel capacity, an MTOW of 275 tonnes (606,000 lb), similar to the A340-300, and minor reinforcements to the undercarriage.

The former was an 18-hour, 45-minute 'westbound' (actually a polar route northbound to 130 km (70 nm) across the North Pole, then south across Russia, Mongolia and the People's Republic of China) and the latter was an 18-hour, 30-minute eastbound, 15,344 kilometres (8,285 nmi; 9,534 mi) journey.

[125] This was primarily attributed to its perceived inefficiency, as it carried a relatively low number of passengers while still retaining most of the heavy structural elements of its larger sibling, the A340-600, from which it was derived.

Furthermore, operating in the specialized ultra long-haul market proved challenging, given the substantial fuel load required for such extended flights, making it a segment where profitability was hard to achieve.

[citation needed] Designed to replace early-generation Boeing 747-200/300 airliners, the A340-600 can carry 379 passengers in a three-class cabin layout for 13,900 km (7,500 nmi; 8,600 mi).

[132] It has an MTOW of 380 t (840,000 lb) and a range of up to 14,630 km (7,900 nmi; 9,090 mi), made possible by strengthened structure, increased fuel capacity, more powerful engines, and new manufacturing techniques like laser beam welding.