The thesis work aims are: the development of a Methodology for the design of new Prototype of Supersonic Aircraft and the analysis of a specific case study, belonging to the same category, which uses LH2 as propellant. The conceived methodology starts from some already existing and adopted formulations concerning the design of conventional aircraft, with some specialization, properly done, to meet supersonic aircraft design and LH2 implementation needs. The formulations and procedures are implemented in a MATLAB® code that represents a 'tool' in which the user enters all the inputs required for the design in order to provide numerical and graphical output to evaluate the viability of the project.