Structural Design Of A Composite Aileron Using AMulti-step Integrated Procedure

Abstract

This work describes the structural design of a composite material aileron of a business aircraft with the target of weight reduction with respect to the metallic reference baseline. It proposes a multi-step procedure for the design and analysis of a composite material structure. A carbon-epoxy material is used for the structural item. An integrated procedure (FEM/analytical and computational formulations) for the design and analysis is developed. In the first level the structural item is considered as concentrated elements. The internal loads are evaluated by elementary theory and a preliminary layup configuration for the structural components (skin, spar, etc.) is chosen by means of a stand-alone approach using a structural sizing software. In the next step a finite element model of the structural item is developed with the preliminary layups, and a general-purpose finite element software is used to evaluate the internal FEA loads acting on the different structural components. Finally the finite element model (geometry and internal loads) is imported into the structural sizing software, which chooses, for the different structural parts, the best layup satisfying the minimum weight requirement. The iterative procedure FEM/structural sizing software is defined and it runs until a convergent solution is obtained. The aileron is designed at ultimate loads and a weight reduction of about 14% respect to the metallic baseline is achieved. The skin and the spar are made of solid laminate and a foam material is used at the trailing edge for shape stability according to RTM technology constraints.