Achieve 100% abort coverage for the Hercules single-stage reusable vehicle (HSRV) concept during Lunar ascent and descent and Mars ascent and EDL. For present crewed launch vehicles at Earth, NASA requires the crew separate from a failed vehicle on the pad or early in flight, but does not require abort late in ascent or for entry. For past lunar mission strategies, including the Apollo LEM and NASA’s Altair program, an expendable two-stage lander was utilized enabling the crew to abort-to-orbit (ATO) during a failed landing attempt; no abort capability for ascent existed. For past human Mars mission architecture study efforts, none have considered safe crew abort and recovery options. A unique secondary propulsion system enables a modular HSRV design with unprecedented crew safety and operational flexibility.