Apollo 15 went unused, due to the explosion that damaged the Apollo 13 spacecraft. Apollo 14's CMP, Stu Roosa, was enthusiastic about geology, but the mission commander, Alan Shepard, less so. Scott, once assigned as Apollo 15 commander, was determined that his crew bring back the maximum amount of scientific data possible, and met with Silver in April 1970 to begin planning the geological training. The assignment of Schmitt as Apollo 15's backup LMP made him an insider, and allowed him to spark competition between the prime and backup crews. The cancellation of two Apollo missions in September 1970 transformed Apollo 15
Apollo Applications Program of the Outer Solar System, and the original "Voyager program" of Mars Lander probes. The Apollo lunar base proposal saw an unmanned Saturn V used to land a shelter based on the Apollo Command/Service Module (CSM) on the Moon. A second Saturn V would carry a three-man crew and a modified CSM and Apollo Lunar Module (LM) to the Moon. The two-man excursion team would have a surface stay time of nearly 200 days and use of an advanced lunar rover and a lunar flier as well as logistics vehicles to construct a larger shelter. The isolation of the CSM