Products
GKN Aerospace develops techniques for rapid deposition of composite materials

May 21, 2008 – With ever more of the airframe content manufactured from composite
materials (some 60% of airframe content on the latest passenger
aircraft) and the aero-engines market now looking more closely at the
benefits of using composites, GKN Aerospace is developing and evolving
automated processes to allow complex structures, whether flat or
curved, for airframe or engine, to be produced swiftly, to a consistent
standard, and cost effectively.

Existing products continue to be produced using traditional
processes as the cost of the re-certification of the part can be
prohibitive. However, new programmes such as the contract for the A400M
primary wing spar, have already offered GKN Aerospace an opportunity to
introduce some automated manufacturing processes. 

For the A400M wing spar – the largest all-composite wing spar ever
produced – the Company has employed Automated Tape Lay-up (ATL)
equipment for the first time in the manufacture of a primary
component.   ATL can lay composite tapes 150mm or 300mm wide at rates
of around 40lb of tape an hour.  This compares with hand lay-up rates
of between 1 and 3 lb/hr. Although the ATL process has required
significant optimisation by GKN Aerospace as the spars are complex
forms that must be manufactured to an extremely high quality, ATL has
proved very successful in production, increasing tape deposition rates
by a factor of 40. 

GKN Aerospace is now exploring the application of Automated Fibre
Placement (AFP).  AFP is a complementary process to ATL.  ATL is
excellent in the production of large, reasonably flat structures but
can cause composite fibre buckling in more highly shaped components. 
AFP, although not as fast in laying-up large flat areas, will lay-up
accurately over far more extreme curves and changes in direction. The
AFP machine does this by using a number of narrower separate tapes to
make up the overall tape width. Each narrow tape is able to start and
stop independently as the head moves across the
complex shape.  GKN Aerospace is evaluating this technology for more
demanding wing spar features and believes it could have great value in
the manufacture of items such as hybrid engine components and acoustic
liners in the engine. 

Frank Bamford, Senior Vice President of Business development and
Strategy at GKN Aerospace concludes:  "As the leading independent
supplier of composite structures for aviation, the development of
effective automated processes is, of course, a key focus for us.  We
are examining all our accepted manufacturing practices and exploring
many innovative ideas and in future we expect to employ a range of
automated processes that will support our highly skilled workforce in
producing complex parts far more swiftly, in greater quantity and more
economically than is possible today."