Aviation Section, U.S. Signal Corps

The Aviation Section, Signal Corps, was the military aviation service of the United States Army from 1914 to 1918, and a direct statutory ancestor of the United States Air Force. It replaced and absorbed the Aeronautical Division, Signal Corps, and was succeeded briefly (four days) by the Division of Military Aeronautics, and then by the Air Service, United States Army. The Aviation Section organized the first squadrons of the aviation arm and conducted the first military operations by United States aviation on foreign soil.

The Aviation Section, U.S. Signal Corps was created by the 63rd Congress (Public Law 143) on July 18, 1914 after earlier legislation to make the aviation service independent from the Signal Corps died in committee. From July 1914 until May 1918 the aviation section of the Signal Corps was usually known by the title of its administrative headquarters component, named variously Aeronautical Division, Air Division, Division of Military Aeronautics, and others. For historic convenience, however, the air arm is commonly referred to during its existence as Aviation Section, Signal Corps, and is the designation recognized by the United States Air Force as its predecessor for this period.

The Aviation Section began in turbulence, first as an alternative to making aviation in the Army a corps independent of the Signal Corps, then with friction between its pilots, who were all young and on temporary detail from other branches, and its leadership, who were more established Signal Corps officers and non-pilots. Despite the assignment of Lieutenant Colonel George O. Squier as chief to bring stability to Army aviation, the Signal Corps found itself wholly inadequate to the task of supporting the Army in combat after the United States entered World War I on 6 April 1917. It attempted to expand and organize a competent arm but its efforts were largely chaotic and in the spring of 1918 aviation was removed, first from the jurisdiction of the Office of the Chief of Signal where it had resided since its inception, and then from the Signal Corps altogether.

1914
The Aviation Section, Signal Corps was created by the Act of July 18, 1914, Chapter 186 (Public Law 143, 63rd Congress), 38 Stat. 514, to supersede the Aeronautical Division, an administrative creation of the Signal Corps within the Office of the Chief Signal Officer (OCSO), as the primary agency for military aviation. Earlier legislation to make the aviation service independent from the Signal Corps died in committee after all officers connected with aviation save one, Captain Paul W. Beck, testified against it. Later provisions of the National Defense Act (39 Stat. 174), June 3, 1916, and the Aviation Act (40 Stat. 243), July 24, 1917, permitted aviation support functions to be gradually transferred from the Aeronautical Division to newly established aviation section organizations. The new law established the purpose and duties of the section, authorized a significant increase in size of U.S. military aviation to 60 officers and 260 enlisted men, increased the size of the Signal Corps by an equal number of personnel to provide them, stipulated that pilots be volunteers from branches of the line of the Army, and detailed them for four years. The Aeronautical Division then became a component of the Aviation Section until its abolition in 1918. The first funding appropriation for the Aviation Section was $250,000 for fiscal year 1915.

The new law also decreed restrictions that only unmarried lieutenants of the line under the age of 30 could be detailed to the section, provisions which encouraged a lack of discipline and professional maturity among the aviators that handicapped the growth of the service, hampered retention of pilots, and prevented flying officers from commanding flying units. Officers on aviation duty who were promoted to permanent captain in their branch arm were automatically returned to the line. Aggravating the situation, the 11 remaining pilots of the 24 previously rated as Military Aviators all had their ratings automatically reduced to Junior Military Aviator (and therefore incurred a 25% reduction in flight pay) when requirements were changed to include three years experience as a JMA before qualifying for the higher rating. This placed them on the same level as newly graduated pilots, and none of those so reduced regained their ratings before 1917.

At its creation, the Aviation Section had 19 officers and 101 enlisted men. The Aeronautical Division, a quasi-headquarters (Lt. Col. Samuel Reber, Washington, D.C.) with three officers and 11 enlisted men, issued orders in the name of the Chief Signal Officer (CSO). All other personnel of the aviation section were organized on August 5, 1914, by Signal Corps Aviation School General Order No. 10 into the: totaling 16 officers, 90 enlisted men, seven civilians, and seven aircraft.
 * Signal Corps Aviation School (Capt. Arthur S. Cowan, San Diego),
 * 1st Aero Squadron (Capt. Benjamin D. Foulois),
 * 1st Company, 1st Aero Squadron (Capt. Harold C. Geiger)
 * 2nd Company, 1st Aero Squadron (Capt. Lewis E. Goodier, Jr.),

Most of the air service had just returned to San Diego from detached service in Texas for the second time in as many years to support Army ground forces in a possible war with Mexico over the Tampico Affair. The impending war was defused by the resignation of Victoriano Huerta on July 15. A small detachment returned to Texas in April 1915, when the Army massed around Brownsville, Texas, in response to civil war between the forces of Pancho Villa and the Carranza government.

By December 1914, the Aviation Section consisted of 44 officers, 224 enlisted men, and 23 aircraft.

1915-1916
Chief Signal Officer Brigadier General George P. Scriven announced on April 9, 1915 that following the establishment of an aero company at San Antonio, three additional companies would be sent overseas, to the Philippine Department for station on Corregidor, to Fort Kamehameha in the Hawaiian Department, and to the Panama Canal Zone. The 1st Company, 2nd Aero Squadron was activated on May 12, 1915 at San Diego but not manned until December.

Beginning in August 1915, the 1st Aero Squadron spent four months at Fort Sill, Oklahoma, training at the Field Artillery School with eight newly delivered Curtiss JN-2s. After a fatal crash on August 12, the pilots of the squadron met with squadron commander Foulois and declared the JN-2 unsafe because of low power, shoddy construction, lack of stability, and overly sensitive rudders. Foulois and Capt. Thomas D. Milling disagreed, and the JN-2 remained operational until a second crashed on September 5. The aircraft were grounded until October 14, when conversions of the JN-2s to the newer JN-3 began, two copies of which the squadron received in early September.

Between November 19 and 26, 1915, the six JN-3s of the 1st Aero Squadron at Fort Sill (the other two were on detached duty at Brownsville) made the first cross-country squadron flight, 439 mi to a new airfield built near Fort Sam Houston, Texas.

The Texas base became the "first permanent aeronautical station" on January 6, 1916, designated as the San Antonio Air Center. Ironically, the first "permanent" base was abandoned after several months and its remaining funding allocated to the establishment of a new training school on Long Island, New York. Signal Corps Aviation Station, Mineola (later Hazelhurst Field) opened on July 22, 1916.

On January 12, 1916, the strength of the Aviation Section stood at 60 officers (23 JMA-rated pilots, 27 student pilots) and 243 enlisted men (eight of whom were pilots). It was now organized into four subordinate organizations:
 * the Aeronautical Division (Washington D.C.),
 * the Signal Corps Aviation School (San Diego);
 * the 1st Aero Squadron (San Antonio Air Center), and
 * the 1st Company, 2nd Aero Squadron (Manila).

It had 23 aircraft: four seaplanes based overseas at Manila, two seaplanes and nine trainers at San Diego, and eight JN-3s in Texas. Thirty-two other aircraft had been destroyed or written off since 1909, one was in the Smithsonian Institution, and three were too damaged to repair economically.

On November 1, 1915, the first aviation organization in the National Guard was created, the "Aviation Detachment, 1st Battalion Signal Corps, New York National Guard", later called simply the "1st Aero Company". Consisting of four officers (including its founder, Captain Raynal Bolling) and 40 enlisted men, it used two leased aircraft to train until five aircraft were purchased for its equipment in 1916.

Punitive expedition


Following Villa's raid on Columbus, New Mexico, on March 9, 1916, the 1st Aero Squadron was attached to Major General John J. Pershing's Punitive Expedition. It consisted of 11 pilots, 84 enlisted men (including two medics), a civilian mechanic, and was supported by an engineer officer and 14 men. Eight Curtiss JN-3s were disassembled at Fort Sam Houston on March 12 and shipped the next day by rail to Columbus, along with the squadron's 12 trucks, one automobile, and six motorcycles. The JN-3s were reassembled as they were off-loaded on March 15, the date the first column marched into Mexico. The first observation mission flown by the squadron, and the first American military reconnaissance flight over foreign territory, was flown the next day and lasted 51 minutes with Dodd at the controls and Foulois observing.

On March 19, Pershing telegraphed Foulois and ordered the squadron forward to his base at Colonia Dublán to observe for the 7th and 10th Cavalry Regiments. The ground echelon moved forward by truck, and the eight JN-3s took off at 17:10. None of the eight aircraft made Dublán that evening: one turned back to Columbus because of engine problems, and one was destroyed by scavengers after a forced landing in Mexico. Four that landed together at Ascensión (about halfway to Dublán) flew on to Dublán in the morning, where they were joined by the plane that had returned to Columbus and one that had landed on a road at Janos.

The squadron returned to Columbus on April 22, where it expanded to a roster of 16 pilots and 122 enlisted men. It flew liaison missions for Pershing's force using detachments in Mexico until August 15, 1916. The 1st Aero Squadron flew a total of 540 liaison and aerial reconnaissance missions, flying 19553 mi with a flight time of 345 hours 43 minutes. No observations were made of hostile troops but the squadron performed invaluable services maintaining communications between ground units deep inside Mexico and Pershing's headquarters. During this expedition, a solid red star on the rudder became the first national insignia for United States military aircraft.

Their airplanes did not have sufficient power to fly over the Sierra Madre Mountains nor did they perform well in the turbulence of its passes, and missions averaged only 36 mi distance from their landing fields. The planes were nearly impossible to maintain because of a lack of parts and environmental conditions (laminated wooden propellers had to be dismounted after each flight and placed in humidors to keep their glue from disintegrating), and after just 30 days service only two were left. Both were no longer flight worthy and were condemned on April 22. Congress in a deficiency bill voted the Aviation Section an emergency appropriation of $500,000 (twice its previous budget), and although four new Curtiss N-8s were shipped to Columbus, they were rejected by Foulois after six days of flight testing. Although recommended for condemnation, they were shipped to San Diego, modified, and ultimately became training aircraft.

A new agency was also created within the Aviation Section, the Technical Advisory and Inspection Board, headed by Milling, and staffed by pilots who had attended engineering course at the Massachusetts Institute of Technology and civilian engineers, including Donald Douglas. The Board recommended the squadron be equipped with new Curtiss R-2s, which used a 160 hp engine.

The first two were delivered on May 1, 1916, and the remaining 10 by May 25. They were assigned Signal Corps numbers 64 to 75. The R-2s were equipped with Lewis machine guns, wireless sets, and standard compasses, but their performance proved little better than that of their predecessors. Pilots were quoted by name in both the New York Times and New York Herald Tribune as condemning their equipment, but Pershing did not pursue the issue, noting they had "already too often risked their lives in old and often useless machines they have patched up and worked over in an effort to do their share of the duty this expedition has been called upon to perform."

Charges and countercharges
In August 1914, soon after the passage of the act creating the Aviation Section, World War I began. The European powers showed an immediate interest in promoting military aviation but the Army's General Staff remained apathetic regarding development of aerial capabilities, as Captain Beck had charged the year before. The Chief Signal Officer continued restrictions on development and acquisition of aircraft that were perceived by the young aviators as detrimental to flying safety and likely to prevent the Aviation Section from providing aviation support to the Army comparable to that of the European powers in the event that the United States was drawn into the war. Officers who had testified against separation of aviation from the Signal Corps in August 1913 now were for it, marking the beginning of the movement that ultimately culminated in the creation of the United States Air Force 33 years later. Considerable friction developed between the young pilots from the line of the Army and their non-flying superiors in the Signal Corps. The commanding officer of the 1st Aero Squadron's 2nd Company at San Diego, Capt. Lewis E. Goodier, was seriously injured in a demonstration accident on November 5, 1914. Flying with Glenn L. Martin in a new aircraft undergoing a required competitive slow speed test, the aircraft stalled, and when Martin overcorrected with too much throttle, went into what was described as the first tailspin. Goodier suffered a nearly severed nose, two broken legs, a re-opened skull fracture, and a severe puncture of his knee from the drive shaft. The accident occurred amidst a series of fatal training crashes, all involving the Wright C pusher airplane, that resulted in six deaths between July 1913 and February 1914, and culminated in pilots refusing to fly pusher airplanes. After a cursory review of the crashes, school commandant Capt. Arthur S. Cowan refused to discontinue use of the aircraft, dismissing the pilots as "nothing but amateurs".

While recuperating, Goodier assisted Capt. Townsend F. Dodd and 1st Lt. Walter Taliaferro in an attempt to prefer charges against Cowan for fraudulently collecting flight pay when he was neither certified to fly nor on flying duty. They were aided by Goodier's father, Lt. Col. Lewis E. Goodier, Sr., Judge Advocate General of the Western Department in San Francisco, who in addition also preferred charges against former squadron commander Captain William Lay Patterson for similar offenses, charging that he had been awarded a rating of Junior Military Aviator, and was drawing pay based on it, without being qualified to fly or being on flying duty.

The charges were routed to the CSO at a time when Cowan's superior, Chief of the Aviation Section Lt. Col. Samuel Reber, himself an integral part of the accusations and also a non-flyer, was temporarily in command. Reber had the charges against Cowan and Patterson dismissed, then he and Cowan charged the elder Goodier with "Conduct to the Prejudice of Good Order and Discipline" for assisting in drawing up of charges against Cowan, specifying that he did so out of malice.

Goodier court-martialed
The resulting court martial proceedings, which began October 18, 1915, resulted in the conviction of Lt. Col. Goodier and a sentence of reprimand. Brig. Gen. E. H. Crowder, the Army's Judge Advocate General, ruled (after the preferring of charges against Lt. Col. Goodier but before his trial) that neither Cowan nor Patterson was criminally culpable of fraud because of legal technicalities. Although legally correct, the ruling put the Army in a bad public light for not only condoning obvious misfeasance but failing to correct it. Evidence also showed that at the same time Reber and Cowan had used Capt. Goodier's injuries as a pretext to have him dismissed from the Aviation Section while he was recuperating.

However the charge of malice allowed defense counsel wide latitude in its introduction of evidence, and documents including official correspondence describing numerous incidents that confirmed Capt. Goodier's original charges against Cowan became part of the court record, including support by the CSO of a pattern of retribution against officers on flying duty who fell in disfavor of Cowan. Senator Joseph T. Robinson immediately brought the matter before the United States Senate, introducing S.J. Resolution 65 in January 1916, calling for an investigation of malfeasance in the Aviation Section involving serious mismanagement, disregard for flying safety, favoritism, fraud, and concealment of wrongdoing in the Aviation Section's chain of command. Robinson conducted hearings and released to the public all of the documents held in evidence at the court martial. S.J. Resolution 65 passed on March 16, 1916, without opposition. An acting head of section was immediately appointed pending the outcome of the investigation.

The second of these acting heads of division was Major William "Billy" Mitchell, a General Staff officer who had testified before Congress in 1913 against transfer of aviation from the Signal Corps. As a result of negative publicity regarding its airplanes in Mexico, Mitchell and the Aviation Section came under severe criticism during this period. Mitchell defended the department, insisting that the U.S. firms did not produce better aircraft, but the outcry produced several long-term results, including instructing Mitchell in political tactics, participation in which ultimately resulted in his court-martial at the end of his career.

Report of the Garlington Board
While the Senate hearings were in progress and the 1st Aero Squadron encountered difficulties with its airplanes in Mexico, Scriven issued a statement accusing the young aviators of "unmilitary insubordination and disloyal acts" in an attempt to form an air service separate from the Signal Corps. He also recommended that the age and marital status restrictions for pilots be removed to encourage older and therefore more experienced officers to volunteer for aviation duty. Brig. Gen. Ernest Albert Garlington, the Inspector General, was appointed by Army Chief of Staff Gen. Hugh L. Scott to head a board of investigation into the Aviation Section. The Garlington Board confirmed Goodier's allegations and also cited Scriven and Reber for failing to supervise the section adequately, holding them responsible for acquiring substandard aircraft. The Garlington Board's report, together with the Senate resolution and public criticism of the equipment used in Mexico, prompted Secretary of War Newton Baker to issue letters of reprimand to Scriven, Reber and Cowan. Reber was formally relieved as Chief of the Aviation Section on May 5, and Cowan of his duties in July. Both were assigned non-aviation duties in the Signal Corps after extensive leaves of absence. Lt. Col. George O. Squier was recalled from duty as military attaché in London and appointed Chief of the Aviation Section on May 20, with orders to reform it literally from the ground up.

On April 24, 1916, the General Staff appointed a committee chaired by Col. Charles W. Kennedy to make recommendations for reform and reorganization of the Aviation Section. Milling was named the representative from the section, over the objections of Foulois, who believed him to be too close to the previous Signal Corps leadership. The committee took statements from all 23 officers then on flying duty with the Aviation Section and found that 21 favored separation of aviation from the Signal Corps. Only Milling and Captain Patterson were opposed to separation—and Patterson was the non-flyer who had acquired his flying certificate through the censured actions of Cowan.

The Kennedy Committee recommended in July 1916 that aviation be expanded and developed, and that it be removed from the Signal Corps and placed under a central agency, in effect endorsing for the first time a call for a separate air arm. The recommendation was quickly attacked by Assistant Army Chief of Staff Gen. Tasker Bliss, who branded the air officers supporting separation as having "a spirit of insubordination" and acting out of "self-aggrandizement". The Kennedy Committee's recommendations were rejected by the War Department, but the issue of a separate Air Force had been born and would not die until separation was finally achieved in 1947.

National Defense Act of 1916


On June 3, 1916, in anticipation of possible U.S. entry in the war in Europe, Congress adopted the National Defense Act of June 3, 1916 (39 Stat. 166, 174, 175), provisions of which authorized an increase in the size of the Aviation Section to 148 officers, allowed the President to determine the size of the enlisted complement, and established the first reserve components for aviation, the Signal Officers Reserve Corps (297 officers) and the Signal Enlisted Reserve Corps (2,000 men). However, anticipating the presidential election of 1916, the normally aviation-friendly Wilson Administration still refused to put forth a budget appropriation request greater than that of the preceding year. Following Scriven's recommendations, the law rescinded the eligibility restrictions for detailing officers to be pilots in the 1914 act.

On August 29, however, Congress followed with an appropriations bill that allocated $13,000,000 (more than 17 times the previous combined allocation) to the military aeronautics in both the Signal Corps and National Guard. By December 7, the force still consisted of a total of only 503 personnel. Squier also created a Field Officers course for aviation at North Island similar to that for the Service Schools in Fort Leavenworth to train field grade officers in the staff administration of aviation. Of the four officers assigned to the course in November 1916, two actually headed the section or its successor.

The Aviation Section's poor showing in Mexico also showed that the U.S. aviation industry was not competitive in any respect with European aircraft manufacturers. No American-manufactured airplane had a vital function, none were mounted with weapons, and all were markedly inferior in speed and other performance characteristics. Further, U.S. companies were distracted by protracted legal battles and in-fighting over licenses and royalties while their European counterparts had been energized by the needs of the battlefield.

The Aviation Act (40 Stat. 243), passed July 24, 1917, transferred aviation support functions from the Aeronautical Division to the following newly established organizations in the Office of the Chief Signal Officer:
 * Engineering Division, April 6, 1917: Procurement and distribution of aviation supplies; later designated Finance and Supply Division; and Engineering Division again on August 2, 1917.
 * Construction Division, May 21, 1917: Air field construction and maintenance; redesignated Supply Division, October 1, 1917, with added responsibility for procurement and distribution of aviation supplies transferred from Engineering Division and vested in subordinate Materiel Section, organized January 24, 1918.
 * Aircraft Engineering Division, May 24, 1917: Research and design; redesignated Science and Research Division, October 22, 1917.
 * Wood Section, August 1917: Airplane lumber contracts; expanded and redesignated Spruce Production Division, November 15, 1917.

The Aeronautical Division was renamed the Air Division (also called the Air Service Division), with functions limited to operation, training, and personnel on October 1, 1917. The Air Division was abolished by order of Secretary of War on April 24, 1918, and OCSO aviation functions realigned to create the Division of Military Aeronautics, with responsibility for general oversight of military aviation; and the Bureau of Aircraft Production, which had charge of design and production of aircraft and equipment.

Failures of expansion


In its final year as a component of the Signal Corps, from the declaration of war on Germany by the United States in April 1917 to May 1918, the Aviation Section developed into parallel air forces, a training force in the United States and a combat force in Europe. After February 1917, the section consisted of three divisions in the OCSO: Administrative, Engineering, and Aeronautical. At the onset of war the Aviation Section consisted of only 65 regular officers, 66 reserve officers, 1,087 enlisted men, and 280 airplanes (all trainers), with more on order. The service had 36 pilots and 51 student pilots. By comparison, the United States Navy's air service had 48 officers, 230 enlisted men, and 54 powered aircraft.

In the United States, the Aviation Section was nearly overwhelmed with the problems of rapid expansion to fight a modern war—the recruitment and training of pilots and mechanics, the production of airplanes, the formation and equipping of combat units, and the acquisition of air bases—while overseas a second force developed as part of the American Expeditionary Force, absorbing most of the experienced leadership of military aviation and taking over much of the expansion responsibilities except aircraft production. This second force, the Air Service of the AEF, used European-built aircraft and training facilities and forced the separation of aviation from the Signal Corps.

Part of this separation occurred when the Aviation Section failed in its most pressing need, the production of new airplanes. Under pressure from the French, the Wilson administration set up a production plan to develop a force of 6,000 pursuit planes; 3,000 observation craft; and 2,000 bombers, a ratio established by Pershing, now commanding general of the AEF. Despite pronounced resistance from the Army general staff, $640,000,000 was funded by Congress to meet this goal (45 times the budget of the preceding year) when Squier, now a brigadier general and advanced to CSO, appealed directly to the Secretary of War.

An Aircraft Production Board was set up under the chairmanship of an automobile manufacturer, Howard E. Coffin of the Hudson Motor Car Company, but the airplane of World War I was not suitable to the mass-production methods of automobile manufacturing and Coffin neglected the priority of mass-producing spare parts. Though individual areas within the industry responded well—particularly in engine production, with the development of the Liberty engine, of which 13,500 were produced—the industry as a whole failed. Attempts to mass-produce European models under license in the U.S. were largely failures. Among pursuit planes, the SPAD S.VII could not be engineered to accept an American engine and the Bristol F.2 became dangerous to fly using one.

Because of this failure, President Wilson determined that the OCSO was too overburdened by tasks to supervise effectively the Aviation Section and created a new subordinate organization, the Division of Military Aeronautics, on April 24, 1918, to assume all the functions and responsibilities for aviation. The DMA was removed from the Signal Corps altogether by executive order, under war powers granted to the president under the newly passed Overman Act, on May 20, 1918, reporting directly to the Secretary of War and effectively suspending the statutory duties of the Aviation Section. Four days later, on May 24, both the DMA and the civilian-headed Bureau of Aircraft Production came under the aegis of a new organization, the Air Service, United States Army. The Aviation Section had been created by an act of Congress and was not formally disestablished until the passage of the National Defense Act of 1920, statutorily creating the Air Service.

Aero squadrons
In January 1917 the CSO advised the House Committee on Military Affairs that during 1917 the Aviation Section would increase in size to 13 aero squadrons: four land plane squadrons based in the United States, three seaplane squadrons to be based in U.S. possessions overseas, and six reserve squadrons for coast defense. By the time of the United States entry into World War I in April, three squadrons (1st and 3rd in the U.S., 2nd in the Philippines) were in service, two (6th for Hawaii and 7th for the Panama Canal Zone) were organizing, and two (4th and 5th, to be based in the continental U.S.) had yet to receive personnel. In March, for planning purposes, the Army Chief of Staff proposed new tables of organization and authorized a total of 20 squadrons, including an additional squadron in the U.S. and six additional for coast defense. However the plan was never implemented because of the war and only 131 of the required 440 officers had been assigned.

During the following year, until the statutory responsilities of the Aviation Section were suspended for the duration of the war plus six months by Wilson's executive order, the Aviation Section rapidly mobilized "aero squadrons" for a mulitiplicity of needs, including combat operations. This resulted in a conglomeration of several classifications by function, as flying squadrons were only a portion of the units required by the Aviation Section and by its successor, the Air Service:
 * Service squadron: Flying units equipped with planes and flying personnel. Enlisted personnel assigned to the squadron consisted of mechanics, radio operators, machine gun armorers and chauffeurs. Service squadrons were eventually classified as "pursuit", "observation" or "bombardment" according to their combat role.
 * School squadron: Support units consisting primarily of aircraft mechanics, performing their work in the hangars and shops at training bases for pilots and observers.
 * Construction squadron: Units which built new airfields, smoothing and grading a field for aircraft landings and takeoffs. They also erected hangars, barracks, shops, barracks, and all the other infrastructure (roads, electricity, water, sewer) needed to establish a new airfield. In the Zone of the Advance in France, new airfields were established quickly as the front line changed.
 * Park squadron (also known as "air park"): Logistical units whose mission was to supply the equipment and supplies necessary for the other squadrons to operate.

In the Air Service of the AEF, one squadron historian estimated that for each flying ("service") squadron, there were at least five support squadrons to maintain its aircraft, airfields and stations, beginning with the park squadrons. Behind them were:
 * Depot squadrons to provide a supply base and a reception point for new aircraft being delivered to the flying squadrons,
 * Repair squadrons at major repair facilities where new aircraft were assembled and parts from old aircraft salvaged, and
 * Replacement squadrons for processing and assigning incoming personnel for the flying squadrons.

Chiefs of the Aviation Section
Source:
 * Lt. Col. Samuel Reber (July 18, 1914 — May 5, 1916)
 * Lt. Col. George O. Squier (May 20, 1916 — February 19, 1917)
 * Lt. Col. John B. Bennet (February 20, 1917 — June 30, 1917)
 * Lt. Col. Benjamin D. Foulois (June 30, 1917 — November 12, 1917)
 * Brig. Gen. Alexander L. Dade (November 12, 1917 — February 27, 1918)
 * Col. Laurence C. Brown (February 28, 1918 — April 24, 1918)

Lineage of the United States Air Force

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