 Activated in the summer of 1917 as the Air Service 88th Aero Squadron; deployed to France during World War I and served on the Western Front.Engaged in combat as a corps observation squadron with I, III, IV, and V Army Corps, 30 May – 10 November 1918.After the armistice subsequently served with VII Army Corps in the occupation force, November 1918 – May 1919 when the squadron returned to the United States.