Jack received his Bachelor's and master's degrees in Aerospace Engineering from the University of Florida. During the Apollo Moon Program he was a lead engineer at TRW Systems Group in Houston, Texas, supporting operations at NASA's Manned Spacecraft Center (now the Johnson Space Center). He developed procedures allowing astronauts to monitor the Apollo Command Module Onboard Guidance and Navigation Computer during atmospheric reentry, and to control the reentry manually should they need to override the computer. He provided real-time reentry support during missions Apollo 9 through Apollo 14, including NASA Mission Control Center backroom support during the extended 6-minute reentry blackout period on Apollo 13.