Extending the use of composites in aerospace

Citation

(2006), "Extending the use of composites in aerospace", Aircraft Engineering and Aerospace Technology, Vol. 78 No. 5. https://doi.org/10.1108/aeat.2006.12778eab.001

Extending the use of composites in aerospace

Extending the use of composites in aerospace

Keywords: Aerospace technology, Aircraft components

GKN Aerospace has recently delivered the first all-composite wing spar for the Airbus A400M military airlifter. These 20m long spars is thought to represent the first ever application of carbon composites for a primary structure on a large transport aircraft wing. The wing on the A400M incorporates two front and two rear spars, each in two sections and, in a unique development, each with fully integrated carbon pads to enable associated structures, such as engine nacelles and flap track beams to be attached to them. These sections will be jointed together with an innovative composite splice joint to minimise weight.

To fulfil this contract, the company has taken full advantage of developments in knowledge-based engineering (KBE) including the application of CATIA V5 in the design process. In the manufacturing process, GKN Aerospace's use of advanced and innovative automated processes will mean sections measuring up to 14.5m long x 2.5m wide can be produced in 24h compared with a typical timeframe of 6-8 days. The use of the latest in automatic tape laying (ATL) techniques, innovative “double diaphragm forming” processes and highly accurate Henri Line machining will ensure the final spar is built to a tolerance of just 0.25mm and is finished to the high standard typically associated with finely machined metallic components.

Also, working with Airbus on contracts for composite assemblies for the wings of the pioneering A380, GKN Aerospace has developed and applied an entirely new composite manufacturing system called resin film infusion (RFI). The Company is now extending the application of this new process into the manufacture of aero- engine nacelles and components, such as inlets and fan cowl doors. RFI can involve the laying up of dry multi-axial fabric interleaved with resin film which is then cured using either an oven or heated tools. This process has many advantages over more traditional methods. It reduces manufacturing cycle times and component weight, offers improved product quality and consistency, eliminates the limitations to part size caused by the need to cure the part in an autoclave, and brings dramatic manufacturing cost savings.

GKN Aerospace is an independent supplier of composite structures to the aerospace market and is a driving force in the growing use of composites across military transport and fighter aircraft as well as many commercial airliners. As part of the company's strategic drive to maintain its technological lead, the company has opened an advanced composites facility (ACF) at its facility on the Isle of Wight, UK.

The ACF is described as one of the most advanced research and production facilities of its type in the world today. It incorporates a pioneering manufacturing facility, where the A400M spars are now being produced, alongside a research centre which is focussed on evolving methods to further the automation of the composite manufacturing process.

Phil Grainger, Group Technical Director, GKN Aerospace, states: “We believe we will significantly reduce the recurring costs inherent in the composite manufacturing process today and, with our world leading capabilities already developed, make composites more broadly applicable across airframe and engine structures.”

Details available from: GKN Aerospace, Tel: +44 (0)1983 283649.