The United States Army Air Corps (USAAC) was the predecessor of the U.S. Army Air Forces (USAAF) from 1926-41, which in turn was the forerunner of today's U.S. Air Force (USAF), established in 1947. Although abolished as an organization in 1941, it existed as a branch subordinate to the USAAF from 1941-47.
The Air Corps was created from the Air Service in 1926 largely as a compromise between advocates of a separate air arm and those of the command structure of the United States Army who viewed the aviation arm as an auxiliary branch to support the ground forces. Members worked to promote the concept of airpower between 1926 and 1941, but as a branch of the Army similar to the Signal Corps or Quartermaster Corps, its primary purpose within that period remained support of ground forces rather than independent operations. Today, the Army maintains an Aviation Branch as a subordinate element fulfilling some roles of ground force support, although it is unrelated to the original USAAC.
** The Air Corps became a subordinate element of the Army Air Forces, and no longer an administrative organization, on June 20, 1941. It continued to exist as a combat arm of the Army (similar to Infantry) until disestablished by Congress with the creation of the U.S. Air Force in 1947.
Another board, headed by Dwight Morrow, had already reached an opposite conclusion in only two and one-half months. Appointed in September 1925 by President Calvin Coolidge ostensibly to study the "best means of developing and applying aircraft in national defense" but in actuality to minimize the political impact of the pending court-martial of Billy Mitchell and to preempt the findings of the Lampert Committee, the Morrow Board issued its report two weeks before the Lampert Committee's. In accordance with the views of the President, it rejected the idea of a department of defense and a separate department of air, but it recommended several minor reforms including that the Air Service be renamed the Air Corps to allow it more prestige, that it be given special representation on the General Staff, and that an Assistant Secretary of War for Aviation be appointed.
Congress accepted the Morrow Board proposal, and the Air Corps Act (44 Stat. 780) was enacted on July 2, 1926. The legislation changed the name of the Air Service to the Air Corps, "thereby strengthening the conception of military aviation as an offensive, striking arm rather than an auxiliary service." The act created an additional Assistant Secretary of War to help foster military aeronautics, and it established an air section in each division of the General Staff for a period of three years. Other provisions required that all flying units be commanded by rated personnel and that flight pay be continued. Two additional brigadier generals would serve as assistant chiefs of the Air Corps. The Chief of the Air Service, Maj. Gen. Mason Patrick, then became Chief of the Air Corps.
The position of the air arm within the Department of War remained essentially the same as before, that is, the flying units were under the operational control of the various ground forces corps commands and not the Air Corps, which remained responsible only for procurement of aircraft, maintenance of bases, supply, and training. Even the new position of Assistant Secretary of War for Air, held by F. Trubee Davison from 1926 to 1932, was of little help in promoting autonomy for the air arm.
Perhaps the most promising aspect of the act for the Air Corps was the authorization to carry out a five-year expansion program. However, the lack of funding caused the beginning of the five-year expansion program to be delayed until July 1, 1927. The goal eventually adopted was 1,800 airplanes with 1,650 officers and 15,000 enlisted men, to be reached in regular increments over a five-year period. But even this modest increase never came about as planned because adequate funds were never appropriated in the budget and the coming of the Great Depression forced reductions in pay and modernization. Organizationally the Air Corps did double from seven to fifteen groups. (Origin of first seven groups shown here)
|Group||Station||Date activated||Aircraft type|
|18th Pursuit Group||Wheeler Field, Hawaii||January, 1927||PW-9|
|7th Bomb Group||Rockwell Field, California||June 1, 1928||LB-7, B-3A|
|12th Observation Group²||Brooks Field, Texas||1930||O-19|
|20th Pursuit Group||Mather Field, California||November 15, 1930||P-12|
|8th Pursuit Group||Langley Field, Virginia||April 1, 1931||P-6|
|17th Pursuit Group¹||March Field, California||July 1, 1931||P-12|
|19th Bomb Group||Rockwell Field, California||June 24, 1932||B-10|
|16th Pursuit Group||Albrook Field, Canal Zone||December 1, 1932||P-12|
|10th Transport Group||Patterson Field, Ohio||May 20, 1937||C-27 C-33|
Most early pursuit fighters before 1935 were of the Curtiss P-1 Hawk (1926-1930) and Boeing P-12 (1929-1935) families, and most front-line bombers before the 1934 introduction of the Martin B-10 were variants of Keystone LB-6 (36 planes) and B-3A (127 planes) design.
Transport aircraft of the first ten years of the Air Corps were of largely trimotor design, such as the Atlantic-Fokker C-2 and the Ford C-3, and were procured in such small numbers (66 total) that they were doled out one airplane to a base. As their numbers and utility declined, they were replaced by a series of 50 twin-engine and single-engine small transports, and used for staff duties. Pilot training was conducted between 1927 and 1937 in the Consolidated PT-3 trainer, followed by the Stearman PT-13 and variants after 1937.
In 1933 the Air Corps expanded to a tactical strength of 50 squadrons: 21 pursuit, 13 observation, 12 bombardment, and 4 attack. The last open-cockpit fighter used by the USAAC, the P-26, came into service in 1933 and bridged the gap between the biplane and more modern fighters.
The Air Corps was called upon in early 1934 to deliver the mail in the wake of a scandal involving the postmaster general and heads of the airlines. Despite an embarrassing performance that resulted in a number of crashes and fatalities, the investigating boards that followed recommended organizational and modernization changes that again set the Air Corps on the path to autonomy and eventual separation from the Army. A force of 2,320 aircraft was recommended by one board, and authorized by Congress in June 1936, but appropriations to build up the force were denied by the administration until 1939, when the probability of war became apparent. Instead the Air Corps inventory actually declined to 855 total aircraft in 1936, a year after the creation of GHQ Air Force, which by itself was recommended to have a strength of 980.
The formulation of theories of strategic bombing gave new impetus to the argument for an independent air force. Strategic or long-range bombardment was intended to destroy an enemy nation's industry and war-making potential, and only an independent service would have a free hand to do so. But despite what it perceived as "obstruction" from the War Department, much of which was attributable to a shortage of funds, the Air Corps made great strides during the 1930s. A doctrine emerged that stressed precision bombing of industrial targets by heavily armed long-range aircraft.
This doctrine resulted because of several factors. The Air Corps Tactical School moved in July 1931 to Maxwell Field, Alabama, where it taught a 36-week course for junior and mid-career officers that included military aviation theory. The Bombardment Section, under the direction of its chief, Major Harold L. George, became influential in the development of doctrine and its dissemination throughout the Air Corps. Nine of its instructors became known throughout the Air Corps as the "Bomber Mafia", eight of whom (including George) went on to be generals during World War II. Conversely, pursuit tacticians, primarily Capt. Claire Chennault, Chief of the school's Pursuit Section, found their influence waning because of repeated performance failures of pursuit aviation. Finally, the doctrine represented the Air Corps' attempt to develop autonomy from the General Staff, which enforced subordination of the air arm by limiting it to support of ground forces and defense of United States territory.
New bomber types under development clearly outperformed new pursuit types, particularly in speed and altitude. In both 1932 and 1933, large-scale maneuvers found fighters unable to climb to altitude quickly enough to intercept attacking Y1B-9 and B-10 prototypes, a failure so complete that Brig. Gen. Oscar Westover, following the 1933 maneuvers, actually proposed elimination of pursuits altogether. The successful development of the Martin B-10 and subsequent orders after 1935 for more than 150 (including its B-12 variant) continued the hegemony of the bomber within the AAC. The B-10 featured innovations that became standard for the next decade: an all-metal monoplane, closed cockpits, rotating gun turrets, retractable landing gear, internal bomb bay, and full engine cowlings.
The superiority of bombers resulted in a 1934 feasibility study for a 35-ton 4-engined bomber (the Boeing XB-15) that, while found to be unsuitable for combat because of inadequate engine size, led to the design of the Model 299, later to become the B-17 Flying Fortress, whose first flight was in July 1935. In June 1936 the Air Corps requested 11 B-15s and 50 B-17s for reinforcing hemispheric defense forces in Hawaii, Alaska, and Panama. The request was rejected on the basis that there were no strategic requirements for aircraft of such capabilities.
The Army and Navy, both cognizant of the growing movement within the Air Corps for independence, cooperated to resist it. In September 1935, they issued a "Joint Action Statement" that reasserted the limited role of the Air Corps as merely an auxiliary to the "mobile Army" in all its missions, including coastal defense. However, the bomber advocates interpreted its language to mean that the Air Corps could conduct long range reconnaissance, attack approaching fleets, reinforce distant bases, and attack enemy air bases, all in furtherance of its mission to prevent an air attack on America.
In 1937 the War Department, seeking to stifle procurement of the B-17, decided that it would develop and procure only twin-engined medium bombers in fiscal years 1939 and 1940, and refused funding for further experimental development of a very long range bomber. In collaboration with the Navy, it placed a moratorium on the long range bomber program in June 1938 by issuing a Joint Board ruling that it could foresee no use for a long range bomber in future conflict. However the moratorium would last only a year, as it went against not only the trends of technological development, but against the geopolitical realities of coming war.
Between 1930 and 1938 the Air Corps had obtained a mission in coastal defense that justified both the creation of a centralized strike force and the development of 4-engined bombers, and was lobbying for another mission, strategic bombardment, with which it could persuasively argue for independence from the Army.
GHQ Air Force took all combat air units in the United States out of the control of corps area commanders, where they had resided since 1920, and organized them administratively into four geographical districts (which later became the first four numbered air forces) and operationally into a strike force of three wings. The General Staff perceived its creation as a means of lessening Air Corps autonomy, not increasing it, however, and GHQ Air Force was a "coordinate component" along with the Air Corps, and not subject to its control. However all its members, along with members of units stationed overseas and under the control of local ground commanders, remained part of the Air Corps. This dual status and division of authority hampered the development of Air Corps for the next six years, as it had the Air Service during World War I, and was not overcome until the necessity of expanding the force occurred with the onset of World War II. The GHQ Air Force remained small in comparison to European air forces. On its first day of existence, the command consisted of 60 bombers, 42 attack aircraft, 146 pursuits, and 24 transports. Lines of authority were also difficult as GHQ Air Force controlled only combat flying units within the continental United States, with the Air Corps still responsible for training, aircraft development, doctrine, and supply, and the ground forces corps area commanders still controlling their installations and the support personnel manning them. The commanders of GHQ Air Force and the Air Corps, Major Generals Frank Maxwell Andrews and Oscar Westover respectively, clashed philosophically over the direction in which the air arm was heading, adding to the difficulties, with Andrews in favor of autonomy and Westover espousing subordination to the Army chain of command. The air arm embraced strategic bombing as its primary doctrine after the creation of GHQ Air Force, but could only buy a few of the new four-engined B-17 Flying Fortresses, so that by 1938 there were still only thirteen on hand and orders for more had been suspended.
In January 1936, the AAC contracted with Boeing for thirteen Y1B-17 prototypes, enough to equip one squadron for operational testing with the thirteenth aircraft for stress testing, with deliveries made from January to August 1937. The cost of the aircraft disturbed both Army Secretary Harry Woodring, who denied requests for further purchases, and Army Chief of Staff Malin Craig, who in 1938 reversed plans for five squadrons of B-17s (67 airplanes) to be purchased with carryover funds. The Air Corps also incurred the enmity of the Navy by widely publicizing an interception on May 12, 1938, of the Italian ocean liner Rex by three B-17s while it was 725 miles off-shore of New York City. Craig placed a 100-mile restriction on all off-shore flights in response, and the services issued a joint statement reasserting that the mission of the Air Corps was only that of a support auxiliary for Army ground forces, or for supporting the Navy if called upon to do so.
Even with the doctrine of strategic bombardment as its priority, the Air Corps sought to modernize its tactical combat force under GHQ Air Force, bringing into service the Northrop A-17 and Douglas B-18 Bolo in 1936, Seversky P-35 in 1937, and the Curtiss P-36 in 1938. However all of these aircraft were obsolete by the time they came into service, and development of more modern airplanes continued.
General Arnold, at the direction of President Franklin D. Roosevelt in January 1939, oversaw an expansion of the Air Corps that saw it double in size from 15 to 30 groups by the end of 1940. In March 1939, with the replacement of Gen. Andrews as commander of GHQ Air Force by Maj. Gen. Delos C. Emmons, Arnold was also nominally assigned to "supervise" the tactical force. The problems of lack of unity of command, however, were again exacerbated by the assignment to Army GHQ of GHQ Air Force. Gen. Emmons, who had begun his tour junior to Arnold, was promoted to lieutenant general to make him equal to the commanders of the field armies also controlled by Army GHQ. This forced him to report to and act under an inferior in rank (both Arnold and his acting replacement as chief of the Air Corps, George H. Brett, were major generals). On June 20, 1941, to end the divisions, the War Department revised Army Regulation 95-5 to create the Army Air Forces with the Air Corps and GHQAF (the latter redesignated as Combat Command) as its major components, authorized an Air Staff to manage planning and execution of expansion of the air arm, and named Arnold as Chief of the Army Air Forces.
During World War II the role of the Air Corps changed again. On March 9, 1942, with the issuance of War Circular 59, the Air Corps was further subordinated to the USAAF as a combatant arm (as Infantry and Field Artillery were subordinate combatant arms of the Army Ground Forces) and the office of Chief of the Air Corps was abolished. The Congress did not disestablish the Army Air Corps until July 26, 1947, with the passage of the National Security Act of 1947 (61 Stat. 502).
The Air Corps tested and employed a profusion of pursuit, observation, and bomber aircraft during its 15-year history. The advent of the all-metal monoplane, enclosed cockpits, retracting landing gear, enclosed bomb bays, and the emergence of strategic bombardment doctrine led to many designs in the mid and late 1930s that were still in use when the United States entered World War II. Among the key technology developed were oxygen and cabin pressurization systems, engine superchargers (systems essential for high-altitude combat), and the Norden bombsight.
As a further consequence of the Air Mail Scandal, the Baker Board reviewed the performance of Air Corps aircraft and recognized that civilian aircraft were far superior to planes developed solely to Air Corps specifications. Following up on its recommendation, the Air Corps purchased and tested a Douglas DC-2 as the XC-32, which subsequently became the flying headquarters of Gen. Andrews. The XC-32 so exceeded Air Corps specifications that 17 were purchased to equip the first operational transport unit, the 10th Transport Group, activated in June 1937 at Patterson field, Ohio. In 1939 the Air Corps recognized the importance of modern air transports and purchased 35 DC-2/DC-3 hybrids, designated the C-39, the forerunner of the thousands of C-47 Skytrains that served in World War II.
Notable fighters developed during the late 1930s were the P-40 (first flown October 1938), P-38 (January 1939), P-39 (April 1939), P-51 (October 1940), and P-47 (May 1941). Bombers developed during this period were the A-20 (first flown October 1938), B-25 (January 1939), B-24 (December 1939), and B-26 (November 1940). Except for the B-24, P-47 and P-51, all had production deliveries begun before June 1941. Three other long-range bombers began development during this period, though only mockups were produced before World War II: B-29 (study begun in 1938), B-32 (June 1940), and B-36 (April 1941).
General Arnold transferred a group of experienced officers to his headquarters as an air staff to lay out a plan over the winter of 1938-1939 that would increase the Air Corps to 50,000 men by June 1941. The expansion program of the Air Corps was characterized by repeated upward revision of goals for increasing the numbers of combat units, aircraft production, training new personnel, and constructing new bases. New combat groups were created by detaching cadres from existing groups to provide the core of the new units, with the older groups providing the basis for an average of three new groups.
The initial "25-group program" for air defense of the hemisphere, developed in April 1939, called for 50,000 men. Following the successful German invasion of France and the Low Countries in May 1940, the "54-group program" followed, although funding approval could not keep pace and an inclusive "41-group program" was actually implemented. An "84-group program", with an eventual goal of 400,000 men by 30 June 1942, was begun in March 1941, although not publicly announced until 23 October 1941.
When war broke out in September 1939 the plan was already halfway to its goal in manpower, but with only 800 first-line combat aircraft. The Air Corps had 17 major installations and four depots, and most of its 76 airfields were co-located at civil airports or were small fields on Army posts. The acceleration of the expansion programs resulted in an Air Corps of 156 airfields and nearly 100,000 men by the end of 1940. 20 civilian flight schools and eight technical training schools were contracted to provide additional training facilities, and on 10 August 1940, Pan American Airways was enlisted to provide meteorolgical and navigation training at Coral Gables, Florida, until military schools could be established.
At this stage, public opinion support of airpower reached unprecedented highs, but General Arnold made a decision to postpone any attempts to exploit the opportunity to push for an independent Air Force. Assured of a free hand by Army Chief of Staff General George C. Marshall, Arnold felt it would "be a serious mistake to change the existing setup" in the midst of the crucial expansion effort.