This study is performed as a joint task under NATO-STO Applied Vehicle Technology panel. The purpose of this task group is to extend the knowledge base for understanding, developing, and applying multidisciplinary methods that can fuse physics and data from multiple information sources of varying fidelity to improve the design of military vehicles. Participation to this task group from ITU Faculty of Naval Architecture and Ocean Engineering is carried out by Prof. O. Goren, Assoc. Prof. D.B. Danisman and Dr. H. Pehlivan-Solak. The hull-form design of the DTMB 5415 model (Arleigh Burke-class guided missile destroyer) is handled for optimal resistance performance in calm water. The design performance is assessed using a variety of physical models and solvers (from potential flow models to Reynolds-Averaged Navier Stokes equations). It is shown how the proposed multi-fidelity approaches are able to achieve significant design performance improvements, even if only a few high-fidelity computations are used.