Airbus Delays A350 Final Assembly Start, First Flight
Aviation Daily Apr 20 , 2010 ,
Longer-than-anticipated design activities for the A350XWB twin widebody are forcing Airbus to delay the aircraft’s final assembly start and first flight by several months.
Nevertheless, the aircraft maker still plans to deliver the first A350-900 as scheduled in mid-2013.
“Three months of buffer have been used,” says A350 program chief Didier Evrard.
The three months were lost on a variety of efforts. One was to take more time to complete detailed finite element model work, fully refining the center wing box configuration, and to optimize fuselage damage tolerance. Extra work was also needed on the fuselage electric structural network.
Under the new schedule, final assembly starts at the end of the third quarter 2011, rather than the end of the second quarter, and first flight has slipped to the third quarter f 2012.
The time also allowed developers to conduct further analysis to shave weight from the total, says program chief engineer Gordon McConnell. On one structural element alone, that effort achieved 60 kg of weight reduction.
Most of the systems development remains on schedule, Evrard says.
The schedule adjustment compresses flight testing to 12 months from 15 months. Airbus will have five test aircraft to log about 2,600 flight test hours.
Meanwhile, wind tunnel testing and computer modeling show that long-range cruise speed is slightly above the Mach 0.85 target. Low-speed performance also has improved, with 475 ft. better takeoff performance and four metric tons higher takeoff weight performance in hot-and-high conditions, McConnell says.
Airbus also has launched a program to create some additional buffer in case it is needed.
There are no changes to the -800 and -1000 schedules, Evrard notes.
Airbus also has set up a special organization to work on the -1000, the largest member of the family. Its design freeze is planned next year. Evrard says the -1000 could feature technology upgrades since the selection was made for the lead version, the -900. Evrard says there are strategic decisions to be made on the -1000 that the personnel focused on birthing the -900 cannot address. Still, the 400 people will have close ties into the overall program to keep the A350 family concept alive, Evrard stresses.
Among the issues to be looked at might be whether composites could be used in parts of the landing gear.
The first Rolls-Royce TrentXWB engine to test is now in assembly for first run at the end of May. Seven engines are to run in the first six months. The TrentXWB will be airborne in the second quarter 2011 on the first A380 (MSN001).
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