The article presents the photofit approach to requirements justification for design characteristics and evaluation of the flight capabilities of the next-generation vehicles. It is demonstrated that in the "question-answer" mode it is possible to effectively sort out various vehicles configurations options; dimensional and aerodynamic characteristics; onboard equipment, controls, communications and other elements of a vehicle in order to obtain the necessary input data for the subsequent flight simulation, design optimization, evaluation of the possibility to resolve various tasks and maximum use of the flight and service performance. Using the photofit principle enables the determination of justified requirements to the function of vehicles; increases the efficiency of design processes; and essentially enhances the efficiency of simulators for training of pilots and operators of remotely-piloted aircraft systems.