759) rebuked these ideas but did establish the Air Service as a statutory entity (previously it had existed by executive order only) and assigned it status as a "combatant arm of the line.

[5] Maj. Gen. Charles Menoher, Director of Air Service, wrote the War Department in October 1919 for permission to establish a tactical school at Langley Field, Virginia, to train field grade officers in the operation and tactics of the Air Service as a requirement for higher command or staff work.

[7] Major Thomas DeWitt Milling was assigned as officer-in-charge of the Field Officers Course at the new school and sent to Langley in July 1920 to set it up.

The second class, beginning in October 1921, was devoted to the further training of instructors, the creation of a sound administrative system, and development of a well-rounded course curriculum.

[12] While at Langley, the ACTS was hampered by a chronic shortage of instructors, caused by a lack of policy within the Army for filling vacancies despite a rapid turnover in staff in the first three years.

The situation was somewhat ameliorated in August 1924 when the Chief of the Air Service authorized extended duty for instructors, most of whom afterwards served four-year tours on the faculty, with an overlap between incoming and outgoing staff.

Approximately 290 hours involved technical subjects, including aeronautical engineering, armament and gunnery, navigation, meteorology, and photography, and 150 to administrative studies, covering staff duties, combat orders, organization of the Army, military and international law, supply and courses in equitation and stable management.

Restructured by the Tactical School faculty, who doubled as its members, the Board was directed by the War Department to formulate Air Corps doctrine.

[26] After the move to Maxwell, the practice of requiring students to fly actual missions as part of the instruction process was discontinued for safety reasons.

Plans for a composite school group were suspended by the Chief of the Air Corps because of a service-wide shortage of personnel and aircraft, and attempts to have demonstrations by existing combat units were mostly unsatisfactory.

The limited class size at the Tactical School led the Air Corps in 1938 to study the feasibility of using a series of shorter courses to allow a greater number of officers to attend.

The plan had the drawbacks of limiting the amount of detail to which students could be exposed, and would require a rebuilding of the staff and curriculum when the long course was reinstated.

This shift in emphasis from pursuit to bombardment was the result of two factors: the air war theories of the time and the state of aviation technology.

Going beyond Mitchell's ideas, they de-emphasized balanced forces and support of ground troops in favor of a doctrine that heavily armed bombers could fight their way to industrial targets in daylight, unescorted by fighters, and with precision bombing (made possible by the introduction of the Norden bombsight in 1931),[30][31] defeat an enemy by destroying key war production targets, rather than engaging in costly and prolonged ground campaigns aimed at destroying enemy armies.

[32] While the theory was based on tenets of strategic airpower developed by Mitchell, Hugh Trenchard, and Giulio Douhet,[33] it rejected the concept of terror-bombing of civil populations as a means of destroying the morale and coercing the will of an enemy state.

They viewed war in the abstract, admitted (and even apologized for) being unable to offer conclusive proof of their theories,[36] but firmly believed that the dominance of airpower lay ahead in the future, when existing limitations of technology had been overcome.

The unofficial leader of the group was the bombardment section chief and later director of the Department of Air Tactics and Strategy, Major Harold L.

[2][37] The doctrine brought them in conflict with the Army General Staff, which did not view airpower as a major striking arm but as an auxiliary to the ground forces.

[38] Although flawed and tested only under optimal conditions, the doctrine (originally known as the "industrial web theory")[39] became the primary airpower strategy of the United States in the planning for World War II.

Four former instructors of the school, the core of the "Bomber Mafia", produced the two airpower war plans (AWPD-1 and AWPD-42) that guided the wartime expansion and deployment of the Army Air Forces.

Combined with a centralized early warning and control system (which came with the development of radar), defending interceptors would inflict serious losses on unescorted forces.

[2][40] The doctrine also ran counter to the theories of Billy Mitchell, who believed that pursuit support was essential for daylight bombing operations.

When his tour at ACTS ended, the fighter-versus-bomber controversy became a moot point among the staff, to the detriment of developing a role for escort fighters.

[42][43] Although the proponents of daylight precision bombing at the Tactical School had a "failure of imagination" in not expanding the doctrine to include establishing air superiority as a prerequisite for success,[44] and thus contributed to the delay in the development of a long-range escort fighter until two years into the war, the doctrine nonetheless became the foundation for the separation of the Air Force from the Army, and the basis for modern airpower theory.

[2] ACTS graduate, instructor, and "Bomber Mafia" member Haywood S. Hansell, concurred that both the theorists and the authors of the AWPD-1 war plan (he was both) made a serious mistake in neglecting long-range fighter escort in their ideas.

However, the press of the enormous tasks confronting the Air Corps and the primacy of strategic bombing doctrine meant that development of a long-range capability for these new fighters was not undertaken until combat losses to bombers forced the issue.

The need for experienced officers to supervise the expansion led to plans to reduce the size of the faculty and long course classes as a compromise to keep the school functioning.

Instead the Air Corps Board was moved to Eglin Field, Florida and absorbed by the Air Corps Proving Ground, while all remaining staff of the Tactical School were transferred to Washington, D.C., where they continued work (mainly the production of training literature) until 30 June 1942, after which the school went unstaffed until its formal dissolution in 1946.

[52][53] The senior service school function was abandoned for the duration of World War II in favor of development of an actual tactical center, responsible for the mass teaching of all aspects of air warfare to inexperienced officers who would become commanders of newly created units.

Established in 1946, AU coordinated all professional education for Air Force officers, and "fell heir to the purpose and tradition of the old Tactical School".