At the start of World War I he joined the Royal Flying Corps, where he served as assistant to David Henderson and Hugh Trenchard in France. In 1918, Baring served as a staff officer in the Royal Air Force and was appointed Officer of the Order of the British Empire in the 1918 Birthday Honours. In 1925 Baring received an honorary commission as a wing commander in the Reserve of Air Force Officers. After his death, Trenchard wrote, "He was the most unselfish man I have ever met or am likely to meet. The Flying Corps owed to this man much more than they know or think."