Commander Towers was ordered to the Bureau of Navigation as Supervisor of the Naval Reserve Flying Corps, a precursor to the Naval Air Reserve Force. When the Navy established the Division of Aviation, at Navy Department headquarters, Towers was appointed Assistant Director of Naval Aviation. In that position, he orchestrated the buildup from a handful of obsolete aircraft and fewer than 50 pilots to a force of thousands of aircraft and aviators. Towers was subsequently awarded the Navy Cross for his wartime service as Assistant Director of Naval Aviation. Interwar years, 1919–1939 During the interwar years, Towers was the leading advocate of Naval Aviation (and especially carrier aviation) when there was virtually no other support within or outside of the navy. He was involved in a number of pioneering developments in Naval Aviation, including the first transatlantic crossing by aircraft; serving as commander of the first U.S. aircraft carrier, ; and holding important positions (including bureau chief) within the Bureau of Aeronautics (BuAer), the organizational structure established for naval aviation in 1921. Transatlantic crossing: Flight of NC-4, 1919 In 1919, then-Commander Towers proposed, planned and led the first air crossing of the Atlantic. Planning for the mission actually began during the early years of World War I, when Allied shipping was threatened by submarine warfare, but could not be accomplished prior to the war's end. The flying expedition began on 8 May 1919 when three Curtiss NC Flying Boats, designated NC-1, NC-3 and NC-4, left Naval Air Station Rockaway, New York, The aircraft made intermediate stops in Chatham, Massachusetts and Halifax, Nova Scotia before reaching Trepassey, Newfoundland on 15 May 1919. On 16 May they left for the longest leg of their journey, to the Azores. NC-1 and the NC-3 were both forced to land in heavy seas due to dense fog, and neither could take off again. NC-1 subsequently began taking on water and the crew was rescued by the Greek freighter Ionia. The crew of the NC-3, including Towers, managed to keep the NC-3 afloat for 52 hours, water taxiing the craft over 200 miles to Ponta Delgada on São Miguel Island. NC-4 went on to complete the transatlantic crossing, arriving at Lisbon on 27 May. For his leadership in the operation, Towers was awarded his second Navy Cross. He was also made a commander of the Order of the Tower and Sword by the Portuguese government on