Mission Analysis of Launch Abort System of a Manned Spacecraft via Trajectory Simulation and Aerodynamic Numerical Modelling

The purpose of the presented work is to design and analysis flight dynamic of launch abort system of a manned spacecraft in the conceptual stage of development. To this goal, through studying of various conventional configurations and based on the mission considerations, two main variants are selected and several analyses are performed on them for the evaluation of aerodynamic performance in different flow regimes and operational scenarios. Moreover, the effect of exhaust jets of scape tower nozzles on the flow pattern around launch abort system is investigated. The results of simulations indicate that the strut-based low-mounted nozzle configuration has lower drag force in different flight conditions. On the other hand, less interaction between the exhaust jets and spacecraft body is favorably observed for the adaptor-based high-mounted nozzle configuration. The second variant has extra drag due to four projected nozzles that can be handled via redesigning of scape rocket and its nozzles. Accordingly, the final concept of launch abort system of considered manned spacecraft is proposed. Based on the aerodynamic solutions, flight dynamic simulations are carried out for the assessment of designed flight path and the results show that the presented aerodynamic configuration has met the flight path requirements of launch abort mission.