Supersonic Retropropulsion Thrust Vectoring for Mars Precision Landing

Landing heavier payloads with pinpoint precision on the surface of Mars is a known challenge for future missions to Mars. Supersonic retropropulsion has been proposed as a means to deliver higher-mass payloads to the surface, traditionally with the sole intent of deceleration. By adding range control capability during the supersonic retropropulsion maneuver by means of thrust vectoring, it has been found that a substantial amount of propellant can be saved in a precision landing scenario when compared with traditional architectures. Decreasing the propellant mass necessary for the mission increases the amount of payload mass that can be brought to the surface. Propellant mass savings greater than 30% are possible if thrust vectoring is unconstrained during the supersonic phase of flight. Propellant mass fraction is found to be sensitive to the divert direction and also the altitude and flight-path angle at ignition, favoring low altitudes and shallow flight-path angles. Decreased nozzle cant angles and aerodynamic drag preservation have also been found to reduce propellant usage.