Optimization of the Mars Ascent Vehicle for Human Space Exploration

This paper presents an analysis of the ascent stage to be used in future human missions to Mars, commonly known as the Mars Ascent Vehicle. The focus of the analysis is to minimize the initial mass, which must be delivered to low-Earth orbit to have a fully functioning Mars Ascent Vehicle. At the end of the surface mission, the Mars Ascent Vehicle takes the astronauts from the Martian surface to the orbiting Earth Return Vehicle. Systems analysis tools are used to help identify the most influential mass drivers. The main focus of the analysis is on the optimization of the propulsion system, including the type of propellant, oxidizer-to-fuel ratio, type of feed system, nozzle area ratio, and initial thrust-to-weight ratio of the system. A full factorial analysis shows that oxygen/hydrogen, pump-fed engines with a two-stage cryocooler are the best option for a mission scenario for propellant brought from Earth. If in-situ resource utilization is used to produce the necessary propellant on the Martian surface, oxygen/methane pump-fed engines become the best option in terms of minimizing the initial mass in low Earth orbit.