In January 1923, Hickam became assistant commandant of the Advanced Flying School, Kelly Field, Texas, and commanded the 10th School Group to 1 August 1925. In November 1925, while a student at the Air Service Tactical School at Langley Field, Virginia, he testified on behalf of airpower and a separate Air Force before the Morrow Board, appointed by President Coolidge and chaired by Dwight Morrow to offset adverse political effects of the court martial of Billy Mitchell. After graduation from ASTS, Hickam next was a student at the Command and General Staff College (Fort Leavenworth, Kansas) 1926–27, and at the Army War College (Washington, D.C.) 1927–28, as preparation for a four-year detail to the War Plans Division of the General Staff.