Farnborough Air Show

Airbus keeps A350XWB on the 787’s tail

 - July 16, 2010, 11:30 PM

While it seems like the A380 first flew only a short time ago, Airbus is well into its next program–the A350 XWB (eXtra widebody). The planned family is scheduled to begin operations in mid-2013 competing against the Boeing 787 (expected to enter service early next year) and some variants of the 777, which began commercial flights in 1995. Manufacturing of the first A350 began last year and final assembly plants are under construction in France, Germany and the UK.

The XWB variant arose after Airbus abandoned the proposed 222-inch diameter cross section of the A300, A310, A330 and A340 programs for a new, wider structure. Its 10-abreast seating, not previously available from Airbus, will accommodate up to 475 passengers in stretched, high-density variants.

A350 product marketing director Sophie Pendaries said the -800, -900 and -1000 variants constitute a “single family well positioned for a market of over 5,000 aircraft with the right capacity mix and right cross section.” And, at a briefing in May, customer and business program development v-p Francois Caudron said Airbus had orders for 530 aircraft from 33 customers, including three private customers and five lessors, adding that the A350 “industrial setup is on track with ‘extended-enterprise’ suppliers on board.”

Detailed design of the initial A350-900, which will hold 314 passengers in a three-class layout, has been completed as Airbus continues to establish manufacturing facilities. According to A350 deputy chief engineer Alain de Zotti, A350-900 design work is well advanced, with first parts manufactured and major development testing started.

The second model, which is scheduled for service entry in 2014, is the A350-800 with 270 seats, compared with 220 in the equivalent Boeing 787-7. Detail definition is under way, following design freeze at the end of last year. The A350-800 and -900 offer up to 900 nm more range than the 787-8 and 787-9, said Pendaries.

Still in the concept phase, with design freeze planned for 2011 and service entry four years later, is the 350-passenger A350-1000. The A350- 800 and -900 will be powered by 84,000-pound thrust Rolls-Royce Trent XWB engines, while the larger -1000 will be equipped with 93,000-pound-thrust units.

Systems Commonality
The Series 800 and 900 will enjoy a high level of structural and systems commonality. The two models share a forward fuselage, outer and center wingbox, rear fuselage and empennage, wing leading and trailing edges and related high-lift devices, and engine pylon. Compared with the Series 900, smaller Series 800s will sport modified forward- and aft-fuselage geometry, including re-sizing of the forward section 13/14 and aft section 16/18 and the center fuselage upper shell.

Among the common systems are landing gear, flight controls and hydraulics, slat/flap actuators, shafts, power-control unit and wingtip brakes, the auxiliary power unit, fuel and inerting systems, and the electric power generation and distribution. Both variants have an optional 79,000-pound engine-thrust rating. A350-800 systems differences from those of the -900 include adapted crew oxygen and fire-extinguishing bottles, flight control software and six rather than seven cabin ventilation zones.

The larger Series 1000 has increased design weights and payload, stretched fuselage (six frames forward of the wingbox and five aft), reinforced airframe structure and revised wing trailing edge. Its main landing gear adopts six-wheel bogies accommodated in a one-frame-longer undercarriage bay, while the engines feature “bespoke fan module and core technology.” Air conditioning also is modified.

Airbus is aiming to reach program maturity at service entry through a series of structure-and systems-testing pyramids involving design, component and subassembly demonstrators and systems integration, full-scale airframe structures and “iron-bird” systems testing. Caudron said technology readiness will involve fuselage, pylon and wingbox demonstrators. Some 84 percent of overall tools had been deployed among major partners and all A350 work programs had been allocated as of this May.

According to Airbus, it has learned from the challenges it endured with the A380, on which commonality issues arose between manufactured parts and assembled structures. Buyers also had too much latitude for cabin customization, the manufacturer said.

Physical and Digital Mockups
Caudron explained that what he called de-risking the manufacturing phase to secure a quick ramp-up in serial production required “a lot of work upfront.” Having also burned its fingers by relying too much on A380 digital mockups (DMU), Airbus has re-introduced a physical mockup (PMU) for the A350.

Engineering centers engaged in A350 work outside Europe include facilities in China and the U.S., said engineering executive v-p Charles Champion. In Beijing, almost 200 engineers work on several projects, including A350 movables such as the rudder and elevators. The U.S. center in Mobile, Alabama, employs about 150 engineers engaged in cabin-related design work.

Manufacturing on the A350 began in late 2009 with the first composites lay-up. Metal-cutting started in March with production of center wingbox attachments, said Caudron, adding that final assembly lines in Toulouse and Hamburg are taking shape. Production of the first aircraft is under way. Initial major parts have included wing and center-wingbox panels and the first forgings.

The 904,000-sq-ft A350 final assembly building in Toulouse is located close to the A330/A340 production line. It is expected to be able to handle more than 10 aircraft a month.

Scheduled for completion later this year, the L-shaped facility covers some 18 acres, with the aircraft halls occupying 570,500 sq ft. There are 226,000 sq ft of ancillary buildings.

Airbus is preparing for production of the 106-foot A350 wings at its UK factory at Broughton in north Wales, where a 495,000-sq-ft facility is being built. To make best use of internal volume, the plant will build the largely composite wings “in the horizontal,” rather than “in the vertical” as with previous such Airbus parts.

‘Branding’ Cabin Products
As well as using both DMUs and PMUs to improve production management, Airbus is working hard to permit A350 operators to brand their cabin products while ultimately limiting their options. “Customization is where the A380 is in trouble: the A350 will be a much more rigid process,” said programs executive v-p Tom Williams.

Customization is offered “where it matters,” said Caudron. The A350 is designed to meet specific operational requirements and to allow operators to differentiate their aircraft from those of other carriers. For example, customers can select from a number of module options–such as trim and finish, color and materials–when choosing cabinet, countertop, mirror, wall panel and flooring. Similarly, there is a range of passenger seat and galley options.

This modular approach aims to give Airbus greater assurance in managing production ramp-up, while offering A350 owners confidence about future residual values since less work will be required in “decustomization.”