The research work presented here is apart of an on-going program in the development of Unmanned Aerial Vehicle system, at the conceptual and preliminary design levels, in Aerospace Research Center (ARC-Egypt). The main objective is the implementation of the developed design process in MDO software for UAV design development. It is applied to the previously proven SAHM UAV platform. A model with a specified design variables has been chosen, while the design constraints are selected to cover the entire UAV modules; geometry, aerodynamic, performance, stability, weight and structure. The design objective is to minimize the air vehicle ground launch weight. The optimization method is the steepest descent with an exterior penalty operator. Results obtained show that all design disciplines are quite matched within the requirements. Generated version of SAHM UAV shows a significant reduction of about 11% in the ground launch weight relative to the baseline design. Modal testing was performed on both the wing and the whole airframe of the SAHM UAV. Natural frequencies, and mode shapes were identified. At the same a detailed FE model of the wing was developed on MSC/NASTRAN. One-way ANOVA has been implemented for the compatibility of the numerical and experimental results, which correlates well.