Optimization of airbreathing propulsion system for the TSTO spaceplane

The Institute of Space and Astronautical Science (ISAS) has proposed a fully reusable Two-Stage-ToOrbit (TSTO) vehicle along the aerodynamic way to LEO. In this paper it is shown TSTO conceptual design methodology. Genetic algorithm (GA) was applied to optimize design parameters of engine, airframe, and trajectory simultaneously. Several types of engine were quantitatively compared using payload ratio as an evaluating function. It was concluded that precooled turbojets is the most promising engine for TSTO among Turbine Based Combined Cycle (TBCC) engines.