Fully-propulsive Mars atmospheric transit strategies for high-mass payload missions

Abstract

A systems analysis focused on the use of propulsion during entry, descent, and landing at Mars is presented. The propellant mass fractions of various fully-propulsive EDL strategies are presented. A key aspect of the study is the propellant costs of meeting specified heat rate constraints and the trade between TPS mass and technology requirements vs those for propulsive deceleration. Propulsive strategies considered include a constant-thrust gravity turn as well as variable-thrust trajectory designs. A control law for heat rate constrained trajectories is provided. Sensitivity to the vehicle's propulsive capabilities is explored. A comparison is presented between the fully-propulsive EDL architecture and EDL systems in which significant aeroassist technology is employed. With this information, an overview of the impact of a fully-propulsive EDL system on spacecraft design and functionality is offered. ©2009 IEEE.