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www.flightglobal.com
Airline criticism of Airbus A350 forces airframer to make radical changes to fuselage, wing and engines
By Guy Norris in Los Angeles
Airbus is working on a dramatic redesign of its planned A350 long-range widebody twin that is aimed at an all-new aircraft family capable of leapfrogging the rival Boeing 787 as well as the 777,
Flight International reveals in this week’s issue.
Airbus went back to the drawing board on the A350 after vocal criticism from key customers such as International Lease Finance, and is expected to reveal details of the initiative in July.
The new family is expected to comprise three versions, the A350-800, -900 and -1000. Key design changes from the earlier A350 include a wider fuselage cross-section, larger all-composite wing, higher Mach 0.85 cruise speed and more powerful engines in the 85,000-90,000lb (380-400kN) thrust class.
The -800 is aimed at the 787-3/8/9 and will continue to be billed as Airbus’s A330-200 replacement. The -900 is similarly aimed at the 777-200ER and 787-10, while the -1000, with seating for around 350, will for the first time give Airbus a very large twin with the range and similar payload capability of the 777-300ER.
Flight International understands Airbus internal planning documents claim new technology engines and lighter structural weight will enable it to achieve up to 20% lower fuel burn than the 777-300ER. The adoption of the new cross-section, the first change for any new Airbus single-deck widebody since the original A300 design of the late-1960s, is particularly significant.
The new fuselage, although close to the 777 diameter with the addition of around 500mm (19in), is expected to retain the same materials technology as the original A350. The move to the larger twin concept also means the formal abandonment of Airbus’s fundamental belief in its long-range four-engined policy.
It is understood that the common cross-section is likely to be adopted over an alternative study that favoured retaining the original diameter for the smaller -800/900 and increasing it for the -1000.
While dramatically enhancing the product’s overall competitiveness against both the 777 and 787 families, it will also inevitably delay the development schedule. Under the original A350 plan, Airbus expected to put the first aircraft into service in late 2010. Under the revised schedule, first delivery is expected to be no earlier than 2012.
The new plan would call for the introduction of the -900 first, with the -800 following and the -1000 coming last in late 2013 or early 2014. The move is also pivotal on the engine makers which, in the case of General Electric and Rolls-Royce, were already well-advanced on powerplants. The thrust requirement is now well above the mid-70,000lb level originally expected.
One option would be to retain the existing GEnx-1A72 and Trent 1700 engines for the new A350-800/900 – taking advantage of integration work already completed – and develop modified, higher-thrust derivatives for the -1000. Another would be to develop new baseline engines in the 90,000lb-thrust class and derate them for the smaller models.
The engine requirement for the revamped A350 has also attracted the attention of the GE Pratt & Whitney Engine Alliance (see related story).
Airbus says: “There has definitely been no decision on the A350 taken yet. We have an A350 already which has been successful in the marketplace. We are talking to customers to see if we should do any optimisation. When we have a clearer picture we will take an internal decision on this.”
