CONTENTS. Introduction The GKN Aerospace Western Approach facility... 4

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2 CONTENTS Introduction... 3 The GKN Aerospace Western Approach facility... 4 Spar lay-up A350XWB rear wing spar lay-up... 5 A400M wing spar lay-up... 7 Wing spar manufacture... 8 Wing spar assembly Our team Going forward September 2014 P a g e 2

3 INTRODUCTION GKN plc is a global engineering group. It has four divisions; GKN Aerospace, GKN Driveline, GKN Powder Metallurgy and GKN Land Systems, which operate in the aerospace, automotive and land systems markets. Nearly 50,000 people work in GKN companies and joint ventures in more than 30 countries. GKN is listed on the London Stock Exchange (LSE: GKN) and recorded sales of GBP7.5 billion in the year to 31 December GKN Aerospace is a global first tier supplier of airframe structures, engine components, transparencies and fuel/flotation systems, with sales of GBP2.2bn in 2013 and a global workforce approaching 12,000. It has a significant participation on all major aircraft programmes today and a broad customer base spanning commercial, military, business aerospace and space markets. The company s extensive engineering capability and clear focus on targeted innovation has created technological and manufacturing leads in each of its areas of expertise. GKN Aerospace Western Approach, a centre of excellence within the Europe & Special Products Group, is part of the Composite Aerostructures group together with the Munich and East Cowes sites. September 2014 P a g e 3

4 THE WESTERN APPROACH FACILITY In April 2009, work started on the construction of this state-of-the art composite manufacturing site, which was officially opened in April It produces the Airbus A350XWB rear wing spar and assembled structures and the wing front and rear spars for the Airbus A400M military carrier. The site comprises two buildings: Bristol where both spars are manufactured and Dowlais where the A350XWB rear wing spar is assembled with the fixed trailing edge. The buildings have a combined manufacturing footprint of 28,000m 2 with over 350 employees. Many innovative processes are used at the site to reduce the manufacturing lead time, costs and weight and to meet production rates: Automated tape laying (ATL) Double diaphragm forming (DDF) Automated fibre placement (AFP) Robotic assembly The use of composite structures in the airframe helps reduce weight and cost and contributes towards the production of a more fuel efficient aircraft. September 2014 P a g e 4

5 SPAR LAY-UP Both the A400M rear spar and A350XWB rear wing spar are designed by GKN Aerospace in close liaison with Airbus and both are manufactured using automated deposition processes. A350XWB Rear Wing Spar Lay-up The A350XWB rear wing spar comprises three sections, the inner spar being the thickest section at approximately 25mm thick and weighing several hundred kilogrammes. The spars are built up from carbon fibre prepreg tape, which is made from unidirectional carbon fibres, each typically 8 millionths of a metre (micron) across and pre-impregnated with a high-temperature cure epoxy resin. The prepreg, supplied in rolls, is frozen at -20 o C before use to delay natural curing. The prepreg tape is laid up in ordered layers of different orientation, to ensure that the required strength is achieved in each direction. 0 A350XWB 6mm wide fibre tow creel September 2014 P a g e 5

6 The A350XWB spars are laid up using the AFP machines to wind up to 16 parallel 6mm wide fibre tows simultaneously around a box section mandrel, forming two spars simultaneously. This technique allows individual fibres to be run in more complex shapes than the ATL process, giving both weight and material consumption savings. Bare mandrel before lay-up AFP head in operation laying 16 off 6mm wide carbon tows Lay up of two back-to-back spars, part lay-up completed During the lay-up process, the evolving structure is periodically debulked inside a vacuum bag to cold-compact the structure by removing air-filled voids. September 2014 P a g e 6

7 Western Approach The part is slightly oversize in plan and, due to inherent thickness variations, nonstructural sacrificial layers are manually added in key areas after automated lay-up. These are so that it can be machined back to a defined edge and thickness after cure. A400M Wing Spar Lay-up The longest spar, the A400M outer rear, is ~14 metres long and is laid up from 300mm wide prepreg tape on the ATL, is then hot-draped before being cured over a metal tool to form the classic C spar section. A400M 300mm wide tape roll September 2014 DDF forming machine Page 7

8 WING SPAR MANUFACTURE Both the A350XWB and A400M spars are then transferred to metallic mould tools, accurately machined to define the final shape of the cured spar. The tools are made from Invar, a nickel-iron alloy with thermal expansion similar to carbon fibre. The tools are sealed over with a high temperature nylon film bag and cured for several hours in an autoclave at several atmospheres pressure and a temperature of 180 C. This melts the adhesive in the prepreg and allows remaining voids to be filled. Then the liquid resin hardens. The structurally completed spar is machined, firstly to accurately control thickness in the key areas where sacrificial material has been applied, and secondly to machine the edges of the part. Test pieces for the cure cycle are removed for testing at this stage. Cutting in progress September 2014 P a g e 8

9 The machined part has a single ply of glass-fibre prepreg bonded on in specific areas where there is need for galvanic isolation of the carbon fibre from aluminium parts bolted on at a later stage. The spar is subjected to a thorough automated ultrasonic non-destructive test (NDT) to confirm no defects are present, before it is sent for painting. After spray painting, each spar is then jig-mounted and drilled for assembly of the aluminium brackets that fasten to the inter-spar ribs. On the A350XWB project, this sub-assembly is routed to Dowlais for assembly of the fixed trailing edge (FTE) structure. The A400M spars are sent to GKN Aerospace Filton for final assembly. September 2014 P a g e 9

10 WING SPAR ASSEMBLY Traditionally, a spar is jig located for several stages of assembly and moved from one fixed jig stage to another. On the A350XWB FTE, the jig itself moves through the stages with the spar assembly permanently mounted. The jig-located spar and metallic attachments are drilled off in automated numerical controlled (NC) machines. The spar is lifted off for degreasing before the assembly is finally bolted and sealed. The FTE assembly consists of the three spar sections joined end-to-end in a 27 metre structure. The three jigged spars are accurately located in an integration area and joint plates are fitted and drilled-off. The spars are removed and shipped to the customer at Broughton, side-by-side on a road trailer. September 2014 P a g e 10

11 OUR TEAM GKN Aerospace Western Approach has a highly skilled workforce, covering all functions from design engineering, mechanical and manufacturing engineering, skilled fitters, procurement, logistics, training and maintenance. Not only have we invested in our facility but we have invested in our people, having introduced an NVQ Level 3 training programme in Aircraft Fitting. THE ENVIRONMENT In our manufacturing processes we endeavour to be as ecological as we can and some of the measures that we have introduced are multiple-loading of autoclaves and oven, working with the Customer to use materials with minimum environmental impact and recycling waste where there is a current recycling route. We are also actively looking in to recycling more of the materials that currently go to waste in the industry (such as carbon fibre edge offcuts and autoclave bagging plastics). GOING FORWARD GKN Aerospace Western Approach was built for the manufacture of the all composite A350XWB rear wing spars, but has been designed in such a way as to make it an extremely flexible factory space that is able to manufacture wing spars for most types of aircraft, ranging from large civil and military to business jet. Aircraft production is forecast to increase in the next 20 years. The use of composites for primary structures is becoming the norm and GKN Aerospace Western Approach has not only the composite process technology but also the capacity to meet the increase in production rates. After the initial investment of 170m, GKN Aerospace Western Approach continues to invest in the site, continuously seeking to improve processes to further reduce aerostructure weight, manufacturing cycle time and cost. September 2014 P a g e 11

12 GKN Aerospace Western Approach Govier Way Western Approach Bristol BS35 4GG United Kingdom Tel.: +44 (0) Fax: +44 (0) Web: September 2014 P a g e 12