Design of Aircraft Structures - Structural Design of Carbon Fiber Composite Wing for the SARAS Civil Transport Aircraft

National Aerospace Laboratories has undertaken the design and development of a Carbon Fiber Composite\ud (CFC) wing for SARAS Production Standard Aircraft (PSA) replacing the existing metal wing in SARAS\ud Prototype Aircraft (please see the figures below). The optimisation of the CFC layup was carried out for\ud minimum weight design of the wing subject to structural design constraints on strength and stiffness. While\ud the strength constraints were based on Yamada-Sun failure theory, those on stiffness were based on Panel\ud Buckling Factors (PBF) on compressive skins and shear webs. The design optimisation was carried out\ud using SOL 200 of MSC/NASTRAN where the PBF were enforced through deployment of DRESP2 secondary\ud response feature of the optimizer. The details of the design optimisation process, the results and their\ud discussions are presented