United States Army Air Corps

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. Although its members worked to promote the concept of airpower and an autonomous air force between 1926 and 1941, as a branch of the Army similar to the Signal Corps or Quartermaster Corps, its primary purpose by Army policy remained support of ground forces rather than independent operations.

Lineage of the United States Air Force

 * Aeronautical Division, U.S. Signal Corps 1 August 1907–July 18, 1914
 * Aviation Section, U.S. Signal Corps 18 July 1914–May 20, 1918
 * Division of Military Aeronautics 20 May 1918–May 24, 1918
 * U.S. Army Air Service 24 May 1918–July 2, 1926
 * U.S. Army Air Corps 2 July 1926–June 20, 1941 **
 * U.S. Army Air Forces 20 June 1941–September 18, 1947 **
 * United States Air Force 18 September 1947–Present

** The Air Corps became a subordinate element of the Army Air Forces, and no longer an administrative organization, on 20 June 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.

Creation of the Air Corps
The Lassiter Board, a group of General Staff officers, recommended to the Secretary of War in 1923 that the Air Service be replaced by a force of bombardment and pursuit units to carry out independent missions under the command of an Army general headquarters in time of war. The Lampert Committee of the House of Representatives went far beyond this modest proposal in its report to the House in December 1925. After eleven months of extensive hearings, the committee proposed a unified air force independent of the Army and Navy, plus a department of defense to coordinate the three armed services.

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. The Air Corps retained the "Prop and Wings" as its branch insignia through its disestablishment in 1947.

Congress accepted the Morrow Board proposal, and the Air Corps Act (44 Stat. 780) was enacted on 2 July 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.

The act for the Air Corps gave 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 1 July 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 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)

Air Corps Groups added 1927-1937 ¹Disbanded on 20 May 1937 ²Redesignated 17th Attack Group (1935), 17th Bomb Group (1939)

As units of the Air Corps increased in number, so did higher command echelons. The 2nd Wing was activated in 1922 as part of the Air Service, and then renamed the 2nd Bombardment Wing in 1929 when the 1st Bombardment Wing was also activated. A third wing, initially called the 3rd Attack Wing, was activated in 1932, at which time the 1st Bomb Wing was redesignated the 1st Pursuit Wing. The three wings became the foundation of General Headquarters Air Force upon its activation in 1935.

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 all-metal monoplane were variants of the radial engined Keystone LB-6 (60 LB-5A, LB-6 and LB-7 planes) and B-3A (127 B-3A, B-4A, B-5, and B-6A planes) designs. Between 1927 and 1934, the O-1/A-3 Falcons (183 observation and 154 attack aircraft) fulfilled the observation/close support role designated by the General Staff as the primary mission of the Air Corps.

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.

Strategic bombardment in roles and missions
In March 1928, commenting on the lack of survivability in combat of his unit's Keystone LB-7 and Martin NBS-1 bombers, Lt. Col. Hugh J. Knerr, commander of the 2nd Bombardment Group at Langley Field, Virginia, recommended that the Air Corps adopt two types of all-metal monoplane bombers, a short-range day bomber and a long-range night bomber. Instructors at the Air Corps Tactical School, also then at Langley, took the concept one step further in March 1930 by recommending that the types instead be light and heavy, the latter capable of long range carrying a heavy bomb load.

The Air Corps in January 1931 "got its foot in the door" for developing a mission for which only it would have capability, while at the same time creating a need for technological advancement of its equipment. Chief of Naval Operations Admiral William V. Pratt was desirous of having all naval aviation including land-based coastal defense aircraft tied to carrier-based fleet operations. Pratt reached an agreement with new Army Chief of Staff Douglas MacArthur that the Air Corps would assume responsibility for coastal defense beyond the range of the Army's Coast Artillery guns, ending the Navy's role in coastal air operations. Though the Navy repudiated the statement when Adm. Pratt retired in 1934, the Air Corps clung to the mission, and provided itself with the basis for development of long range bombers and creating new doctrine to employ them.

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. On 11 September 1935, the Joint Board, at the behest of the Navy and the concurrence of Gen. MacArthur, 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. The edict was issued with the intent of shoving an upstart Air Corps back into its place. 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. The lack of inter-service cooperation on coastal defense fostered by the Joint Board agreement continued until culminating in the Japanese attack on Pearl Harbor.

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
The next major step toward creation of a separate air force occurred on 1 March 1935 with the activation of a centralized operational air force, commanded by an aviator and answering to the Chief of Staff of the Army. Called General Headquarters (GHQ) Air Force, the command had existed in Army planning since 1924, as a subordinate element of an Army General Headquarters that would be activated to control all Army units in case of war mobilization. In anticipation of war with Cuba in 1933, the headquarters had been created but not staffed on 1 October. Among the findings of the Baker Board, established in the wake of the Air Mail scandal, was that GHQ Air Force be set up as a permanent peacetime tactical organization to both ameliorate the pressures for a separate air force and to exploit emerging capabilities in airpower. In the absence of a general headquarters, GHQ Air Force would report to the General Staff.

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 operationally into a strike force of three wings, and administratively into four geographical districts that later became the first four numbered air forces. 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 and a 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 on 12 May 1938, by widely publicizing an interception of the Italian ocean liner Rex by three B-17s while it was 610 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. By October 1940, over a year before the United States was drawn into the war, every piston-driven single-engine fighter used by the USAAF in World War II was in flight test except the P-47. 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.

Problems with unity of command
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. The separation of the combat organization (GHQ Air Force) from the logistic organization (Air Corps) created serious problems of coordination. 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, but divisions were not entirely resolved. On 5 October 1940, Arnold drew up a proposal for creating an air staff, unifying the air arm under one commander, and giving it autonomy with the ground and supply forces—a plan which was eventually adopted in March 1942—and submitted it to Chief of Staff George C. Marshall, but it was immediately opposed by the General Staff in all respects.

Instead, the two organizations were separated again by a directive from Marshall on 19 November 1940. GHQ Army was activated (over five years after the activation of GHQ Air Force) and GHQ AF placed under it. Its logistical and training structure remained under direct control of the chief of staff and its airfields under corps commanders. However Arnold had joined the General Staff as acting "Deputy Chief of Staff for Air" on 11 November 1940, a position that enabled him to coordinate the two sections of the air arm until the organizational problems were repaired. Even so, Maj. Gen. George H. Brett, acting Chief of Air Corps in Arnold's absence, denounced the plan as "disastrous in war".

The problems of lack of unity of command were further exacerbated by the assignment of GHQ Air Force to Army GHQ. General 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 Brett were major generals). On 20 June 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 9 March 1942, with the issuance of War Department 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, which replaced Army General Headquarters) and the office of Chief of the Air Corps was abolished. The Congress did not disestablish the Army Air Corps until 26 July 1947, with the passage of the National Security Act of 1947 (61 Stat. 502).

Most members of the Army Air Forces, however, also remained members of the Air Corps. In May 1945, 88 per cent of officers serving in the Army Air Forces were commissioned in the Air Corps, while 82 per cent of enlisted members assigned to AAF units and bases had the Air Corps as their combat arm branch.

New aircraft
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).

Expansion of the Air Corps
In a special message to Congress on 12 January 1939, President Roosevelt advised that the threat of a new war made the recommendations of the Baker Board inadequate for American defense and requested approval of a 6,000-plane Air Corps. On 3 April 1939, Congress allocated the $300 million requested by Roosevelt for expansion of the Air Corps, half of which was dedicated to purchasing planes to raise the inventory from 2,500 to 5,500 airplanes, and the other half for new personnel, training facilities, and bases. In June the Kilmer Board recommended several types of bombers needed to fulfill the Air Corps mission that included aircraft having tactical radii of both 3,000 miles (modified in 1940 to 4,000) and 2,000 miles. Chief of Staff Gen. Craig, long an impediment to Air Corps ambitions, was about to retire, and the General Staff reversed itself and concurred in the requirements, ending the brief moratorium on bomber development and paving the way for work on the B-29.

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 meteorological 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.

Army Air Corps, March 1, 1935

 * SOURCE: Maurer Maurer, Air Force Combat Units of World War II



General Headquarters Air Force
(Maj. Gen. Frank M. Andrews, Langley Field, Virginia)
 * 1st Wing (Brig. Gen. Henry H. Arnold, March Field, California)
 * 7th Bombardment Group, Hamilton Field, California
 * 9th, 11th, & 31st Bombardment Squadrons
 * 17th Attack Group, March Field, California
 * 34th, 73rd, & 95th Attack Squadrons
 * 19th Bombardment Group, March Field, California
 * 23rd, 30th, 32nd, & 72d Bombardment Squadrons (23rd & 72nd BS based in Hawaii)


 * 2nd Wing (Brig. Gen. H. Conger Pratt, Langley Field, Virginia)
 * 1st Pursuit Group, Selfridge Field, Michigan
 * 17th, 27th & 94th Pursuit Squadrons
 * 2nd Bombardment Group, Langley Field, Virginia
 * 20th, 49th, 54th, and 96th Bombardment Squadrons (54th detached to Air Corps Tactical School)
 * 8th Pursuit Group, Langley Field, Virginia
 * 33rd, 35th & 36th Pursuit Squadrons (37th Attack Squadron attached)
 * 9th Bombardment Group, Mitchel Field, New York
 * 1st, 5th, 14th & 99th Bombardment Squadrons


 * 37th Attack Squadron (attached to 8th Pursuit Group)


 * 3rd Wing (Col. Gerald C. Brant, Barksdale Field, Louisiana)
 * 3rd Attack Group, Barksdale Field, Louisiana
 * 8th, 13th, & 90th Attack Squadrons
 * 20th Pursuit Group, Barksdale Field, Louisiana
 * 55th, 77th & 79th Pursuit Squadrons


 * 21st Airship Group, Scott Field, Illinois
 * 9th Airship Squadron, Scott Field
 * 19th Airship Squadron, Langley Field



Other flying units

 * Advanced Flying School, Kelly Field, Texas
 * 40th Attack, 42nd Bombardment, 43d Pursuit Squadrons
 * 39th School Squadron


 * Air Corps Technical School, Chanute Field, Illinois
 * 48th Pursuit Squadron


 * Air Corps Tactical School, (Col. John F. Curry, Maxwell Field, Alabama)
 * 54th Bombardment, 86th Observation Squadrons


 * Rockwell Air Depot, Rockwell Field, California
 * 4th Transport Squadron (Activated 8 July 1935)


 * Second Corps Area, Mitchel Field, New York
 * 97th Observation Squadron


 * Sixth Corps Area, Scott Field, Illinois
 * 15th Observation Squadron


 * Ninth Corps Area, Crissy Field, California
 * 91st Observation Squadron


 * 12th Observation Group, Brooks Field, Texas
 * 12th, 22d, and 88th Observation Squadrons



Overseas units

 * 18th Composite Wing, (Lt. Col. Delos Emmons, Fort Shafter, Hawaii)
 * 5th Composite Group, Luke Field, Hawaii
 * 26th Attack, 40th & 50th Observation Squadrons (23d, 72d BS attached)
 * 18th Pursuit Group, Wheeler Field, Hawaii
 * 6th, 19th Pursuit Squadrons


 * 19th Composite Wing, (Lt. Col. William C. McCord, Albrook Field, Panama Canal Zone)
 * 6th Composite Group, Albrook Field, Canal Zone
 * 25th Bombardment, 7th & 44th Observation Squadrons
 * 16th Pursuit Group, Albrook Field, Canal Zone
 * 24th, 29th, 74th & 78th Pursuit Squadrons


 * 4th Composite Group, Clark Field, Luzon
 * 2nd Observation, 3d Pursuit & 28th Bombardment Squadrons

Annual strength
Strength as of 30 June of each year

Chiefs of the Air Corps

 * Maj. Gen. Mason M. Patrick, 2 July 1926–December 13, 1927
 * Maj. Gen. James E. Fechet, 14 December 1927–December 19, 1931
 * Maj. Gen. Benjamin D. Foulois, 20 December 1931–December 21, 1935
 * Maj. Gen. Oscar Westover, 22 December 1935–September 21, 1938
 * Maj. Gen. Henry H. Arnold, 29 September 1938–June 20, 1941
 * Maj. Gen. George H. Brett, 20 June 1941–March 9, 1942