Preliminary wing design of a high speed civil transport aircraft by multilevel decomposition techniques

A multilevel decomposition approach for the preliminary design of a High Speed Civil Transport (HSCT) aircraft wing structure is described. The wing design is decomposed into three levels. The top level uses the ACSYNT aircraft synthesis program to generate preliminary weight, mission and performance information needed for the calculations. The optimization criterion is productivity as expressed by a productivity index for a specified mission. The second level of the system performs a basic finite element structural analysis of the wing box. The wing structure is sized for minimum weight subject to structural and aeroelastic constraints. Sensitivity derivatives are computed with respect to the top level design variables. Level 3 performs a detailed stress and buckling analysis of the wing skin panels and thus creates an updated wing weight that is passed to the top level together with the sensitivity information. The methodology will be verified using a baseline HSCT configuration derived from the NASA HiSAIR studies. Currently data acquisition and computer program installation are in progress.