STUTTGART, GERMANY (Dec. 9, 11:45 a.m. ET) — In August, Airbus delivered the A350 XWB (Extra Wide Body) aircraft wing box and keel beam from its Nantes plant to St Nazaire in France for assembly in the airliner's first fuselage central section. Final assembly activity for the complete plane started in Toulouse in November.
Hexcel supplies HexPly M21E/IMA carbon fiber and prepregs to the Nantes plant for the centre wing box and keel beam. Hexcel carbon fibers are used in all A350 XWB primary structures, the US materials company says.
The Hexcel carbon fiber and prepregs are also used by GKN Aerospace in the UK, which uses automated fiber placement (AFP) to make the airliner's rear wing spars. In addition, GKN Aerospace supplies the wing trailing edges and landing flaps - the inboard flaps go direct to Airbus, while the outboard flaps are supplied via Fokker.
Airbus says the 36 square meter center wing box is the largest monobloque composite panel made of carbon fiber reinforced epoxide resin (CFRP) that is produced in Nantes. The A350 XWB wing cover, made at the Airbus plant in Illescas, Spain, is the largest civil aviation CFRP part.
Composites account for 53 percent of materials in the A350 XWB, aluminum for 19 percent and steel for 14 percent, said Klaus Edelmann, team leader research and technology at Airbus in Bremen, Germany.
In a presentation at the AVK composites conference in Stuttgart in September, Edelmann showed stamp formed clips made in carbon fiber fabric-reinforced PPS thermoplastic sheet by Premium Aerotec. The clips are for the A350 XWB upper shell and hold the aircraft's frame to the “stringer”, over which a CFRP skin is applied at Premium Aerotec's plant in Nordenham, Germany.
Edelmann said a “unique folding process over three axes” forms a single complex clip, the first 2,000 of which were delivered at the end of 2008. The clips will substitute many of the 3.5 million small aluminum parts produced by Premium Aerotec annually for Airbus aircraft.
The patented stamp forming process cuts part weight by 40-50 percent, Edelmann said. Partners in the project include the IFW composites institute and Faserinstitut Bremen, along with industrial groups Flow, Frimo, TenCate, Toho Tenax and Xperion.
Premium Aerotec delivered the 13 meters long, four-paneled fuselage segment (barrel) in CFRP for the A350 XWB in November. It will later use a vacuum assisted process (VAP), developed within the Next Generation of Integrated Composite Aerostructures (Nexicos) project, to produce fuselages with integrated stringers in only one infiltration stage.
The first Boeing 747-8 Freighter aircraft was delivered in October to Cargolux in Belgium. Hexcel supplies HexTow IM7 carbon fiber and HexPly prepregs for the GEnx-2B engine's fan blades. It also supplies HexWeb honeycomb and engineered core components in the engine nacelle (housing) and thrust reverser, as well as various secondary structures and interior parts.
In another engine-related project, the IWK materials and plastics processing institute at HSR university in Rapperswil, Switzerland, developed a CFRP composite annulus filler for Rolls-Royce engines as part of an integrated technology demonstrator (ITD) project. These parts fill the space between individual turbine blades and are normally made of aluminum. The CFRP solution saves weight and avoids damage to engine fan blades caused by aluminum fillers that are broken in bird strikes.
ITD was developed within the CAGE3 Sustainable and Green Engine project, part of the EU's Clean Sky joint technology initiative, in which Austrian aircraft composite parts producer FACC also participated.
FACC supplies via Goodrich the “translating sleeve” cladding and its doors for the A350 XWB Rolls Royce Trent engines, and similar components for the Boeing 787. FACC composite parts on the A350 XWB include passenger baggage storage.
A special resin infusion under flexible tooling (rlFT) process developed by FACC produces a center hinge fitting that attaches spoilers to the wing. This will be fitted onto the A350 XWB by the end of 2011.
FACC has applied for a patent for a membrane assisted resin infusion (MArl) process. This facilitates production of frames and stringers in one shot as single parts up to 30 square meters and 40 mm. thickness. Its depth infiltration principle saturates the component with resin from the surface inwards, eliminating x- and y-direction infiltration difficulty.