His three space shuttle flights included Discovery's first mission, launched in August 1984 to deploy three satellites. In 1993 he became manager of the International Space Station Independent Assessment and in 1996 director of NASA's Human Exploration and Development of Space Enterprise Independent Assurance. Hartsfield was assigned to the Manned Orbital Laboratory in 1966 until its termination in 1969, when he was transferred to NASA as an astronaut.