Billy Ray McDonald entered the V-12 program at Washburn Municipal University, and then was sent for training at the Naval Air Station, Olathe, Kansas. He entered Pre-flight Training School in Iowa City, Iowa, and was discharged from there at the war's end. He entered Annapolis in the fall of 1947, but elected not to continue a naval career. He then enrolled at the University of Kansas, graduating with degrees in civil engineering and business. He married the former Mary Jean Hoffman in 1948. They had three children: Carrie, John and Drew.