 Later assigned to Tyndall Air Force Base, Florida, he was promoted to colonel in March 1961.Assigned to the 25th Air Division at McChord Air Force Base, Washington, Garrison served on the command staff and as senior advisor to the Washington Air National Guard through the early 1960s.In August 1965, Garrison returned to combat for the third time in his career, becoming deputy commander for operations (DCO) of the 405th Fighter Wing at Clark Air Base in the Philippines.