Alan Shepard explosion caused the moon landing to be aborted and nearly resulted in the loss of the crew. It became a joke between Shepard and Lovell, who would offer to give Shepard back the mission each time they bumped into each other. The failure of Apollo 13 delayed Apollo 14 until 1971 so that modifications could be made to the spacecraft. The target of the Apollo 14 mission was switched to the Fra Mauro formation, the intended destination of Apollo 13. Shepard made his second space flight as Commander of Apollo 14 from January 31 to February 9, 1971. It was
Apollo PGNCS Apollo PGNCS The Apollo Primary Guidance, Navigation and Control System (PGNCS) (pronounced "pings") was a self-contained inertial guidance system that allowed Apollo spacecraft to carry out their missions when communications with Earth were interrupted, either as expected, when the spacecraft were behind the Moon, or in case of a communications failure. The Apollo Command Module (CM) and Lunar Module (LM), were each equipped with a version of PGNCS. PGNCS, and specifically its computer, were also the command center for all system inputs from the LM, including the Kollsman Instrument built alignment optical telescope, the radar system, the manual translation and