 After a year in Vietnam, he was promoted to lieutenant colonel and returned to Quantico, where he served for three years as an instructor at the Command and Staff College.In 1969, Trainor attended the Air War College, Maxwell Air Force Base, Alabama.During his War College course he was awarded the Anderson Memorial Award for the "best paper dealing with politico-military thought" and designated a "Distinguished Graduate" upon completion of the course in June 1970.