After graduating from the University of Michigan in June 1950, Flint enlisted in the army and enrolled in the Infantry Officer Candidate School.
Over the next few years, Flint used his experience as an assistant professor of military science to complete a master's degree in history at the University of Alabama.
In July 1985, Flint was nominated dean of the academic board,[2] making him the eighth officer to serve in the position and the first not to be a graduate of the academy.
In 1986, Flint introduced a program that would make Zenith Z248 computers available for every incoming freshman cadet, part of a series of modernization efforts at the academy during his administration.
In January 1995, he wrote William Rhenquist, chancellor and head of the board of regents of the Smithsonian Institution, urging him not to remove the Enola Gay from display in response to controversy surrounding the exhibit.