Mattingly was originally assigned as Command Module Pilot for Apollo 13, but he was removed from the crew shortly before launch after exposure to German measles. He never developed the illness and instead helped from the ground as NASA worked out procedures to bring Apollo 13 home after the oxygen tank explosion. That near-flight became one of the defining disappointments and contributions of his career.

He later flew as Command Module Pilot on Apollo 16 while John Young and Charles Duke explored the Descartes highlands. During the return to Earth, Mattingly performed a deep-space EVA — open definition to retrieve film cassettes from the service module — open definition. He then moved into the Shuttle era, commanding STS-4, the final orbital test flight of Columbia, and STS-51C, the first dedicated Department of Defense shuttle mission.

Mattingly's background fit the broader pattern of the early astronaut corps: technical training, operational discipline, and a career built around difficult work before spaceflight. His formal education included Auburn University (B.S. Aeronautical Engineering, 1958). His service background is recorded as Rear Admiral, United States Navy. His personal record also sits alongside a family life recorded as married, one child, a reminder that these careers unfolded within ordinary lives as well as national history.