31 Jan The Airbus A330 and A340
Airbus Industrie, a consortium of European aircraft manufacturers which had provided the first serious competition to the US with its original widebody, twin-engined A-300, had quickly concluded that its success could only be attained with an expanded product line capable of fulfilling several payload and range needs. Subsequently added to this “family” of airliners had therefore been the smaller-capacity, medium- to long-range range, widebody A-310 and the still smaller-capacity, short-range, narrow body A-320. To complete it, however, a long-range widebody, incorporating new technology, had been required to replace first generation, fuel-thirsty, no-longer-economical Boeing 707s and McDonnell-Douglas DC-8s.
Market studies, however, had indicated the need for two different aircraft. The first of these, tentatively designated “B9,” had been for a medium-range, twin-engined design intended for high-capacity transcontinental, DC-10 like routes, and had initially been conceived as a larger A-300 with a stretched fuselage, its existing wing, and the most powerful turbofans then available. So configured, it would have required 25-percent less fuel than the comparable, tri-engined DC-10.
The second, the “B11,” had been the quad-engined intercontinental design which had sparked the project’s inception.
Costs for two such aircraft, however, had been prohibitive, and design of a single wing, which could structurally and aerodynamically support both two and four pylon-mounted engines, became the core of commonality between the two and the economic solution to the joint launch of both.
In order to differentiate between its narrow and wide body product line, Airbus Industrie redesignated these design studies with “TA” prefixes to indicate their “twin aisle” configurations. The “B9” had therefore been re-identified as “TA9” and the “B11” had been branded the “TA11.”
Powered by CFM56 turbofans, which developed between 27,000 and 30,000 pounds of thrust, they had evolved through numerous iterations, with engine number reflecting intended mission length. In 1982, for instance, the TA9, featuring a 27.9-foot longer fuselage than that of the original A-300, had accommodated 410 single-class passengers on the main deck and five pallets in the forward hold and 14 LD-3 containers in the aft hold on the lower deck. Incorporating much of the technological advancement introduced on the A-320, however, the joint TA9/TA11 project had featured its cockpit, side stick controls, and fly-by-wire, or electronic signaling, flight surface actuation, by 1985, mated to a variable-camber wing to augment lift.
By January 27 of the following year, the Airbus Industrie Supervisory Board had redesignated the designs A-330 and A-340, corresponding to the original TA9 and TA11 model numbers, and finalized their detailed technical definitions with the then envisioned launch customers of Lufthansa and Swissair. Because of route requirements, they had demonstrated far greater interest in the quad-engined version than the twin.
A briefly explored collaboration with McDonnell-Douglas, in which a single design, designated AM-300 and incorporating the A-330’s wing and the MD-11’s fuselage, had quickly waned because Airbus Industrie had refused to consider McDonnell-Douglas’s tri-jet configuration. The MD-11 had resultantly become the A-340’s competitor, since both had been intended for the same market.
The Airbus Industrie’s design, entering a second major evolution, had been able to offer significantly improved performance when it had traded the originally projected CFM56 engines with the International Aero Engine (IAE) V2500-3 Superfan which, on the cutting edge of technology, had incorporated an initial, variable-pitch fan; an almost nine-foot diameter; a 17.5-to-1 bypass ratio; and had produced 32,000 pounds of thrust. Early estimates had promised 15 percent fuel savings, although these had later been reduced by about a third.
The aircraft then envisioned, the A-340-200, had accommodated 262 passengers and had a maximum range of 7,850 miles. A second version, featuring a 14-foot fuselage stretch for a 295-passenger complement, had offered a reduced-range capability, of 7,000 miles, and had been designated A-340-300.
The program’s walls, however, suddenly crumbed when International Aero Engines had abruptly canceled Superfan development due to insurmountable technology obstacles of its very advanced design, and Airbus Industrie had forcibly entered its third major evolution when it had renegotiated with CFM International for engine power. No longer able to meet performance specifications, Airbus had virtually returned to the pre-Superfan configuration, and only with considerable design modifications could the aircraft even approach its intermediate iteration capabilities.
CFM International itself redesigned its core CFM56 engine, increasing its fan diameter to produce greater thrust, and this had resulted in the CFM56-5C1 derivative, while Airbus had increased the common A-330/A-340 wingspan from 183.9 to 192.2 feet, replacing its standard tips with 9.6-foot winglets. Although these modifications, along with a 17,600-pound maximum take off weight increase to 542,300 pounds, had significantly improved the performance over that offered by the initial, CFM56-powered aircraft, range had nevertheless eroded over that of the Superfan version, to 7,700 miles for the A-340-200 and to 6,850 miles for the elongated -300.
Nevertheless, Airbus Industrie had formally announced the launch of the A-330 and A-340 program on June 5, 1987 whose development costs had been reduced by some half-billion dollars because of the type’s airframe and wing commonality, yet at the same time it had been able to cater to differing airline market needs with the same platform. One hundred thirty orders had been received at this time, of which 41 had been for twin-engined A-330s and 89 had been for four-engined A-340s.
The wing, the key to both, had been built by British Aerospace in the UK and had been Europe’s hitherto most ambitious, with the largest span (exceeding 197 feet), greatest sweepback (of 30 degrees), and highest aspect ratio (of 9.3 to facilitate long-range cruise speeds). Although the A-340 had been designed to carry 20 percent more payload and fuel than its twin-engined counterpart, wing-bending moments exerted on the fuselage had enabled it to accommodate either two or four pylon-mounted turbofans. Winglets, covering some 90-percent of the wingtip chord and canted outward at a 42.5-degree angle, had reduced fuel burn by 1.5 percent by harnessing the tip-created vortex where drag-producing pressure differentials had forcibly remixed.
Aerospatiale, one of the Airbus Industrie consortium members, constructed a $411 million, 124-acre final assembly plant in Colomiers, adjacent to the existing facility at the Toulouse-Blagnac Airport in France, to permit up to seven aircraft per month to be completed after their subassemblies and components had been flown from several European sites
The first aircraft, an A-340-300, had been rolled out on October 4, 1991, at which time combined A-330 and A-340 orders had totaled 250, and Airbus Industrie’s first quad-engined, long-range, pure-jet airliner, with a 440,530-pound gross weight, left the ground for the first time 21 days later on October 25. Attaining an altitude of 40,000 feet, it completed a successful four-hour, 47-minute maiden flight, and its test pilots had proclaimed that it had handled like the A-320 on whose fly-by-wire flight controls it had been based.
The A-340-300, with a 208.11-foot overall length, featured a 197.10-foot wingspan and a 3,892.2 square foot area. Identical to the A-330 wing with exception of outer strengthening and a gap between the fourth and fifth leading edge slat to cater to the outboard engine pylon attachment, the wing itself had featured full-span slats, trailing edge flaps, two outboard ailerons, and five outboard spoilers, all operating off of three independent hydraulic systems. Aileron droop increased wing lift. A single rudder had been directly linked to the rudder pedals on the flight deck. The undercarriage, comprised of a twin-wheeled, forward-retracting nose gear; two quad-wheeled, inwardly-retracting main bogies; and a twin-wheeled, rearward-retracting centerline gear; had ensured more even weight distribution, particularly on weaker pavement surfaces.
The aircraft, exit-limited to 440 passengers in a single-class, nine-abreast, 31-inch internal configuration, could alternatively accommodate 335 dual-class passengers with a 30-business and 305-economy class arrangement or 295 three-class passengers in an 18-first class, 81-business class, and 196-economy class configuration, all at varying densities.
The foreshortened A-340-200, which had made its inaugural flight the following year on April 1, 1992, had featured an eight-frame fuselage reduction, resulting in a 194-foot, 11 ¼-inch overall length and permitting 262 three-class passengers in an 18/74/170-arrangement or 303 dual-class passengers seated in a 30-first class and 273-economy class configuration to be accommodated.
After a 2,400-hour, 750-flight test program, which had entailed six A-340-200 and -300 airframes, had been completed on December 22, 1992, the long-range, quad-engined Airbus Industrie design had received its European Joint Aviation Authorities (JAA) type certification on the same day, and US Federal Aviation Administration (FAA) type approval the following year, on May 27, 1993.
Lufthansa, the type’s launch customer, took delivery of its first A-340, a -200 configured for 228 passengers, and inaugurated it into service on February 2, 1993 between Frankfurt and New York, achieving a 30-percent fuel reduction over that of the DC-10-30 it had replaced. It had been progressively introduced on transatlantic routes to many of its other US gateways, among them Atlanta, Boston, Dallas, Houston, Newark, and Washington.
Air France had inaugurated the first stretched A-340-300 into service the following month on the Paris-Washington route, replacing Boeing 747s.
Final assembly of the first twin-engined A-330, which had most closely mirrored the A-340-300, had commenced in February of 1992 with the tenth aircraft off the combined A-330/A-340 production line. Appearing without the outer wing strengthening and fuselage centerline undercarriage bogie, the aircraft, powered by two General Electric CF6-80E1 turbofans, took to the skies for the first time on November 2 at a 400,880-pound gross weight, attaining a 41,000-foot ceiling and completing a successful five-hour, 15-minute flight. Because of experience already gained with its quad-engined counterpart, Airbus Industrie had been able to complete its certification program in only half the traditional time. On October 21 of the following year, it became the first commercial design to simultaneously receive FAA and JAA type certification, and also received FAA cross-crew qualification for the A-320, A-330, and A-340.
Inaugurated into service on January 17, 1994 with Air Inter/Air France Europe on the Paris/Orly-Marseilles French domestic route, the type, designated the A-330-300, had also first flown with Pratt and Whitney PW4168 engines on October 14, 1993 and Rolls Royce Trent 700s on January 31, 1994.
Despite Airbus Industrie’s hitherto strategy of offering progressively larger-capacity, higher gross weight versions, poor sales of the A-330 twin, along with consistent airline demand for a slightly lower-capacity, longer-range version and persistent inroads of its targeted market by the Boeing 767-300ER, had strongly advocated the need for a reverse strategy.
A new version, the A-330-200 with a ten-fuselage frame reduction and a 193.7-foot overall length, had been authorized by the Airbus Industrie Supervisory Board on November 24, 1995. The aircraft, which would entail a $450 million development program, had exchanged structural weight for range and, as a DC-10 and L-1011 replacement, became a viable 767 competitor, offering nine-percent lower direct operating costs than the Boeing contender, yet achieving 6,400-mile ranges. Improved engine reliability, coupled with successful extended twin-engine operations, had rendered it an economical transatlantic airliner able to connect Europe with all but US West Coast cities.
The new version, with a six-foot forward and four-foot aft fuselage reduction, featured the strengthened wing designed for the ultra long-range A-340-300E, and a 3.5-foot taller vertical tail to compensate for the shorter fuselage’s moment-arm. A five-degree increase in rudder travel, to +/- 35 degrees, had also been introduced. Accommodation had entailed 253 tri-class or 293 dual-class passengers. The version’s greatest strength, however, had been its fuel-capacity increase, to 36,700 US gallons, attained by using the formerly dry center section fuel tank, resulting in a vital range increase.
First flying on August 13, 1996, the A-330-200, powered by General Electric CF6-80E1A4 turbofans, had attracted 85 orders from eight carriers at this time, inclusive of Asiana, Austrian Airlines, Emirates, International Lease Finance (ILFC), Sabena, and Swissair. Like the A-330-200, it had eventually been certified with three power plant types.
Although A-330-100 and -500 studies had ultimately led to the all-new A-350 twin, A-340 program developments had occurred in the reverse, or more traditional, direction. Seeking to offer a higher-capacity, Boeing 747 replacement, Airbus Industrie had initially projected a 12-frame fuselage stretch of the existing A-340-300 designated A-340-400X, powered by the existing turbofans, but airline interest had overwhelmingly dictated a larger aircraft.
The final version, the A-340-600, had featured a 19.3-foot forward and 10.6-foot aft, or collective 20-frame, fuselage stretch, resulting in the world’s longest airliner, with a 245.11-foot overall length. Indeed, its aero-elasticity, which resulted in periodic, in-flight bending frequencies, had necessitated the installation of pitch-rate sensors on the fuselage and wings in order to provide feedback and elevator counter-movements, restricting these bending cycles to 2-3 Hz.
An extended wingspan, attained by means of a tapered insert, had produced a 20-percent area increase to 4,703.8 square feet, a 40-percent increase in lift, and a 38-percent increase, of 11,760 US gallons, of fuel. Sweepback had also been increased, from 30 to 31.5 degrees, with an equal increase in the angle of the winglets.
The longer fuselage moment-arm had enabled the lateral axis to be controlled with an almost two-foot shorter vertical tail over that installed on the A-330, but a 38-percent larger horizontal, all-moving composite tail surface had been required to maintain effective pitch control.
Weight distribution had been maintained with a quad-wheeled, forward-retracting centerline undercarriage bogie, increasing aft hold pallet accommodation by two.
The $2.9 billion program, launched on December 8, 1997 with 16 commitments from Virgin Atlantic, had resulted in its first flight four years later on April 23, 2001. Powered by four Rolls Royce Trent 556 engines, the aircraft had been airborne for five hours, 22 minutes.
For carriers placing greater emphasis on range than payload, Airbus Industrie had offered, in parallel with the A-340-600, a lower-capacity, ultra-long range version designated the A-340-500. Featuring a 1.9-foot forward and three-foot aft fuselage plug over the basic A-340-300, the 313 triple-class passenger aircraft, six frames longer than the original -300 series or 14 frames shorter than the -600, had a 221.6-foot overall length and employed the -600’s wing. First flying on February 11, 2002 and certified 11 months later on December 3, it had received initial orders from Air Canada, Emirates, ILFC, and Singapore Airlines. Its extreme range, the longest of any commercial pure-jet airliner, had been demonstrated by several record flights. On February 3, 2004, for example, an A-340-500 operated by Singapore Airlines had flown the 7,609 nautical miles between Singapore and Los Angeles in 14 hours, 42 minutes, while the same aircraft had spanned the 8,963-mile distance to New York five months later on June 28 in 18 hours, 18 minutes.
Having utilized a single airframe-and-wing platform, Airbus Industrie had ultimately succeeded in designing its first high-capacity, long-range airliner, resulting in two twin-engined and four quad-engined versions which had the versatility to replace earlier-generation 707s, DC-8s, DC-10s, L-1011s, and 747s on a wide variety of routes, and, by the end of 2008, had amassed a collective 1,400 sales to over 100 worldwide operators. Its original purpose of completing its Airbus “family” of aircraft had thus been fulfilled.