Fibre Metal Laminate Lower Wing Cover Structures

Fibre metal laminate structures have already been used at Airbus for a number of years in the GLARE A380 fuselage application.  They provide exceptional crack growth performance and hence lightweight solutions. 

Fatigue and damage tolerance are primary design drivers for lower wing covers as well.  With the high loading seen on wings, this drives a lot of weight into a typical metal wingbox.  This is particularly the case on the lower cover, which experiences multiple cycles of high tensile loading through the life of a typical airframe.  Hence activities have taken place within Airbus for a number of years exploring this technology, looking at solutions from the use of selective reinforcement through to full FML wing skins.

Whilst emerging trends are seeing the growth in composites for new wing structures, for small A320 sized aircraft, metal solutions remain highly competitive on a typical weight and cost trade.  FML technologies applied to the lower cover provide the opportunity of significant weight reductions and maintenance reductions, whilst maintaining the lower costs of metal solutions.  The various drivers, requirements and technical challenges of a wing solution will all influence the precise selection of FML architecture to give the optimum design for future wings.