Abstract: One of Ames' long standing science interests has been to robotically drill deeply into Mars' subsurface environment (2 meters, or more) to investigate the habitability of that zone for past or extant life. Large, capable Mars landers would ease the problem of landing and operating deep robotic drills. In 2010, an Ames scientist realized that the crew-carrying version of the SpaceX Dragon capsule would possess all the subsystems necessary to perform a soft landing on Earth, and raised the question of whether it could also soft land on Mars. If it could, it might be a candidate platform for a Discovery or Mars Scout class deep drilling mission, for example.
After approximately 3 years studying the engineering problem we have concluded that a minimally modified Dragon capsule (which we call the "Red Dragon") could successfully perform an all-propulsive Entry, Descent, and Landing (EDL). We present and discuss the analysis that supports this conclusion. At the upper limits of its capability, a Red Dragon could land approximately 2 metric tons of useful payload, or approximately twice the mass that the MSL Skycrane demonstrated with a useful volume 3 or 4 times as great. This combination of features led us to speculate that it might be possible to land enough mass and volume with a Red Dragon to enable a Mars Sample Return mission in which Mars Orbit Rendezvous is avoided, and the return vehicle comes directly back to Earth. This potentially lowers the risk and cost of a sample return mission. We conclude that such an Earth-Direct sample return architecture is feasible if the Earth Return Vehicle is constructed as a small spacecraft. Larry Lemke will present and discuss the analysis that supports this conclusion.