The United States was late in entering World War I, which had been raging in Europe since 1914. It was not until April 1917 that the US declared war, after Germany resumed unrestricted submarine warfare with its U-boats sinking civilian ships.
That October, ground troops of the American Expeditionary Force took their positions in the trenches in Europe. The US air arm came close to missing the war altogether. It began operations at the front in March 1918 and engaged in its first aerial combat in April. That left only seven months before the armistice.
The US Air Service’s contribution was less than that of the other Allies, but it gave a good account of itself and set the stage for postwar expansion.
The Great War was a big turning point for the US armed forces, especially the air forces. The nation had no tradition of preparation for war. In 1916, President Woodrow Wilson was outraged to learn from the newspapers that the War Department was working on plans for manpower mobilization in the event of war.
The US trailed far behind in military matters. Powered flight made its first appearance in the United States at Kitty Hawk, N.C., in 1903, but America could not hold its leadership and European nations moved ahead in numbers of airplanes produced and pilots trained. Even Belgium invested more in aviation.
Between December 1903, when the Wright brothers flew, and summer 1917, when US troops paraded in Paris, the US produced no more than 1,000 airplanes of all kinds and contributed little to the development of military aircraft or tactics.
In 1917, the Aviation Section of the Army Signal Corps had fewer than 250 airplanes. The best of them was the JN-4 Curtiss Jenny. An earlier model, the JN-3, had been used to chase Pancho Villa through Mexico in 1916, but the Jenny was not suitable for any military purpose except training.
Moreover, the nation could not suddenly begin producing combat airplanes. The US did not make any engines with the necessary combination of light weight and high horsepower. Not a single aviation squadron was trained for war.
When the US declared war, it had in Europe only five aviation officers. Fortunately, one was Maj. William “Billy” Mitchell, who did not wait for special instructions to get started. On his own authority, Mitchell set up an office in Paris and was there and holding forth when Gen. John J. Pershing and the American Expeditionary Force staff arrived.
By then, Mitchell had already given Wilson and the War Department a strong nudge about airpower. At his instigation, the French Premier, Alexandre F. J. Ribot, on May 24 dispatched a cablegram asking Wilson to send to France in 1918 some 4,500 airplanes, 5,000 pilots, and 50,000 mechanics. This was needed, he said, to “enable the Allies to win the supremacy of the air.”
The Ribot cable was favorably received in Washington, where war fever was running at full tilt. The War Department concurred summarily with Ribot’s proposal May 27, and on July 24, Congress appropriated $640 million for an aircraft program. Never in its history had the US voted so large a sum for a single purpose.
The program that Congress approved called for 345 combat squadrons, of which 263 were to be in Europe by July 1918. The target was revised the next year, setting the objective at 202 combat squadrons in the combat area and 22,000 airplanes by July 1919. It was an ambitious goal, but when the war ended in November 1918, the Air Service had 45 squadrons at the front and was pushing hard.
The Air Service might have actually reached 202 squadrons had the war lasted another year. The AEF ground and air units infused fresh blood into a tiring Allied effort. The Germans feared, with some cause, that American resources would tip the scales in the outcome of the war.
US airmen mostly flew whatever kinds of airplanes could be obtained from the Allies. Except for the DH-4 reconnaissance-bombers, manufactured on license from the British, nearly all US combat aircraft came from France or Britain, with a few supplied by the Italians. At the end of the war, 80 percent of the airplanes in American service were French-made.
Ten thousand pilots were eventually trained. Dozens of flying schools were set up in the US, but most pilots received some or all of their training in France.
Combat aircraft for advanced training were not available in the United States. The best known of the overseas schools was the US Aviation Instruction Center at Issoudun, 125 miles south of Paris, where Maj. Carl A. Spaatz was commander. Edward V. “Eddie” Rickenbacker, who went to France as a sergeant and was Mitchell’s chauffeur for a while, learned to fly at Issoudun and was commissioned there.
On To France
By the armistice, 28 training schools in the US had graduated 14,176 enlisted mechanics. Others trained overseas. Even so, there was a shortage of mechanics throughout the war.
American volunteers had been flying with British and French forces since 1915. The most famous of the volunteer units was the Lafayette Escadrille, initially called the Escadrille Americaine but changing its name in 1916 after the Germans complained to the US government, which was still neutral. In 1918, pilots from the Lafayette Escadrille transferred to US service as the nucleus of the 103rd Pursuit Squadron.
In the summer of 1917, Pershing divided his Air Service into the Zone of the Advance, responsible for combat operations, and the Zone of the Interior, responsible for logistics and related matters.
Billy Mitchell was promoted to lieutenant colonel and put in charge of the Zone of the Advance. His program sustained a setback in November 1917, when Brig. Gen. Benjamin D. Foulois arrived to become chief of Air Service for the AEF.
As Mitchell described it, Foulois brought along with him a “shipload” of staff officers, “almost none of whom had ever seen an airplane.” Mitchell denounced them as “incompetent” and “carpetbaggers.” Pershing called the Foulois staff “a lot of good men running around in circles.”
In May 1918, Pershing called in his West Point classmate, Brig. Gen. Mason M. Patrick, an engineer, and made him chief of Air Service over both Foulois and Mitchell. The feud persisted. In June, Foulois tried to have Mitchell sent home, but Pershing did not want to lose him. Everyone, including Foulois, recognized Mitchell’s special ability as a combat leader.
A 1918 recruiting poster for the Army Air Service showed the US bald eagle battling the war bird of Imperial Germany in an air-to-air battle.
The matter was finally settled when Foulois overcame his personal feelings and, at his suggestion, Mitchell was given the primary combat role—commander of Air Service for the First Army. Foulois took a position as assistant chief of AEF Air Service under Patrick. Mitchell was the dominant American airman for the rest of the war, rising in October 1918 to the grade of brigadier general as chief of Air Service for the First Army Group, which incorporated all AEF combat forces.
A succession of US squadrons arrived in France in fall and winter of 1917-18. Many of them were assigned to the Toul sector, toward the eastern end of the vast front that stretched across Europe from the Belgian coast to Switzerland. The opposing armies around Toul faced each other in long-established static positions. Day-to-day, not much happened. Both sides used this area between the Meuse and the Moselle Rivers for training new forces.
The first American squadrons flew the Nieuport 28, an elegant and agile fighter with an unfortunate reputation for shedding the fabric from its upper wing when pulling out of a dive. The French did not fly it themselves, preferring the Spad XIII, which was also available by the time the first Nieuport 28s were produced. There were not enough Spads to go around, so the Americans got the Nieuports, which the French were glad to sell. Billy Mitchell called the Nieuport “second class,” but some American pilots liked it better than the Spad.
The 94th and 95th Aero Squadrons received their Nieuports in March and began flying patrols over the lines. On the misty Sunday morning of April 14, observation balloons reported two German airplanes approaching Gengault aerodrome near Toul where the 94th “Hat in the Ring” squadron was based. 2nd Lt. Alan F. Winslow and 1st Lt. Douglas Campbell raced to their Nieuports and took off. They almost collided with the two German aircraft dropping out of the clouds. Winslow shot down the first one, an Albatros D.V. Moments later, Campbell shot down the other intruder, a Pfalz D.III.
These are generally regarded as the first American aerial victories of World War I. However, a case can be made that the first victory should be credited to Lt. Stephen W. Thompson of the AEF, who shot down a German airplane while flying as a volunteer gunner with a French unit Feb. 5.
Likewise, it can be argued that the first US aerial combat of the war was not by the squadrons in the Toul sector but instead by pilots and airplanes of the former Lafayette Escadrille, which merged with the US 103rd Aero Squadron in February 1918. The unit continued its combat operations—but remained under French command until July.
Several balloon companies were formed in the Toul sector, in addition to the fighter, observation, and bombardment squadrons. The balloonists did not get much training in their primary mission, adjustment of artillery, since there was little firing by batteries in the sector, but they did gain proficiency in maneuvering their balloons.
It was an inspiration to airmen when the Royal Air Force was formed as the world’s first independent air force in April 1918. The US was not ready for such a step, but in May the air arm was moved out of the Signal Corps and established as the Army Air Service.
The transition period in the Toul sector came to an end with what Mitchell called “the last grand attack of the German Army.” Beginning in March 1918, Germans launched a series of offensives, hoping to win the war before the flow of American resources became decisive. The first thrusts were at the northern sections of the front, toward Amiens on the Somme and Ypres in Belgium. The third blow was against Allied positions along the Marne. On June 3, the Germans reached Chateau-Thierry, 56 miles east of Paris.
St. Mihiel Salient
Mitchell moved his units from Toul northwest to the vicinity of Chateau-Thierry, where more than half the German fighter squadrons on the Western Front were operating. All three of the “Flying Circuses” were there.
The “Red Baron,” Manfred von Richt-hofen, was dead by then, but his Circus, Jagdgeschwader 1, was capably led by Hermann W. Goering. The American fliers in their Nieuport 28s were pitted against some of Germany’s most experienced pilots in the best German fighter, the Fokker D.VII. The Americans began receiving Spads to replace their Nieu-ports in July, but the conversion was not completed until August. The first Spad was flown in by Eddie Rickenbacker.
The US squadrons were often outnumbered four to one, and they took heavy losses, but the American airmen flew hundreds of strafing, escort, and patrol missions in support of the French and British ground forces. They inflicted a share of losses on the German Air Force.
Among the US casualties was Lt. Quentin Roosevelt, youngest son of Teddy Roosevelt, shot down and killed in his Nieuport 28 behind enemy lines July 14.
The French, stiffened by American ground and air forces, held on at the Marne and threw back the Germans, whose bid to win the war with the summer offensive failed. Furthermore, the balance of power shifted. When the offensive began in March, the Germans had more troops than the Allies, but that summer they took casualties at twice the rate the Allies did and lost their advantage in numbers. American troops, flowing into the battle at the rate of 250,000 a month, widened the gap. In late August, with the Germans dislodged from the Marne, Mitchell moved his pursuit squadrons up to Rembercourt near Verdun for the next phase of the war.
South of Verdun, a bump in the German line extended westward into France, coming to a point at St. Mihiel on the Meuse River. This was the St. Mihiel Salient, 14 miles deep and about 24 miles wide at the base. It had been there since the first months of the war. Pershing, assigned to wipe out the salient, assembled a force of 16 US Army divisions and a French Army corps. Mitchell was in command of the supporting airpower.
Bad weather moved in and Pershing’s engineers advised a delay in the operation because of the rain. Mitchell, the most junior member of the staff, disagreed. He had flown a personal reconnaissance over the salient Sept. 10 and had seen considerable movement toward the rear. He said the Germans were retreating and that the time was opportune to strike.
Pershing was of similar mind and launched his attack at 5 a.m. Sept. 12. Despite the bad weather, hundreds of attack and observation aircraft got airborne that day. As the Army surged forward, US airplanes flew over the battlefield at 50 meters, strafing the enemy trenches and road traffic.
Never before had so large an air fleet been employed in war. Mitchell was in control of 1,481 aircraft, of which 609 were from American squadrons. The others were mainly French and British aircraft, with a few Italians and Portugese.
Mitchell, tutored in the offensive by his mentor, Maj. Gen. Hugh M. Trenchard of the Royal Air Force, used a third of his force in direct support of the ground troops and the rest for bombing and strafing the enemy rear. “Our Air Service, with that of the Allies, went over the [battle] lines, and I was much pleased with the fact that virtually no German airplanes got over our ground troops,” Mitchell said.
The battle was over in a few days. The Germans retreated and the Allies regained the area around St. Mihiel for the first time since 1914. The American airmen, who made 3,300 flights over the battle lines, had done well, as had Mitchell, who coordinated the large operation with notable skill. Pershing praised the air component, which he said had been the eyes of the Army and led it on to victory.
The fighting in September included the dramatic combat run of 2nd Lt. Frank Luke Jr., who shot down 14 German balloons and four enemy aircraft before he was shot down himself and killed on Sept. 29.
The Meuse-Argonne Battle, the last major battle of the war, began Sept. 26. The Germans had fallen back to the heights on the east bank of the Meuse, north of Verdun, and to the Argonne Forest on the west side of the river. It was rugged territory, and the positions were strongly defended, but Pershing had 820,000 troops to throw against them.
This time, Mitchell did not have a force the size of the one at St. Mihiel. He controlled 842 airplanes, a large share of them American. They attacked not only enemy ground and air troops at the front but also German units massing in the rear echelon.
The US airmen introduced a new tactic, “low-flying pursuit,” which assigned patrols of five airplanes each to six-mile fronts. Sweeping along at two levels, they broke up German Army attacks on Allied ground forces. The armies on both sides took terrible casualties as the battle continued through October. In November, the Germans’ string ran out, and the Great War ended when they signed an armistice on terms dictated by the Allies.
World War I was essentially a ground war, with set-piece engagements fought by army divisions operating from static battle lines. The big killer was artillery, raining down destruction on fixed positions along the front. When the war ended, 9.4 million troops had been killed and another 15 million wounded. The number of civilians who died could not be determined precisely.
The Great War was the first large conflict in which submarines, machine guns, and tanks were employed—but the most important of the new weapons was the airplane. It replaced the horse cavalry for scouting and reconnaissance and then evolved to other roles that included pursuit, bombardment, and strafing. Airpower was not yet the major factor in warfare it would become. Airplanes and aerial munitions were still at too early a stage in their development for that.
The American Air Service combat force had grown rapidly, especially in the last months of the war, jumping from 10 squadrons in June 1918 to 45 by November. At the armistice, the US Air Service had 740 airplanes in squadrons at the front. That accounted for a little more than 10 percent of the total aircraft strength of the Allies, up from five percent in August.
In one of the most important and decisive battles of World War I, Mitchell and his pilots made more than 3,000 flights over the battle lines at St. Mihiel.
Back In the Skies
US airmen in World War I shot down 781 enemy airplanes and 73 balloons. They flew 150 bombing raids, the deepest penetrating 160 miles behind German lines. The price of success was 569 American airmen killed or wounded, 654 dead because of illness or accident, and loss of 289 airplanes in combat (including 57 flown by US pilots in British and French units) and 48 balloons.
Seventy-one American pilots became aces, led by Rickenbacker with 26 victories. The term “ace” originated with the French newspapers in 1915. At first, it referred to an excellent pilot but was soon defined as one who had achieved a certain number of aerial victories. The qualifying number varied but it was eventually set at five.
In early January 1919, the Prince of Wales—who was later to become the Duke of Windsor—visited the Air Service at its new headquarters on the Rhine and went flying with Mitchell along the valley of the Moselle in a two-seat Spad. Later that month, Mitchell was awarded the Legion of Honor by France. In a short time, the American airmen had earned the respect of their European Allies.
Airmen, rallying to the flamboyant Mitchell, believed that airpower would be the dominant weapon of the future. The war had proved that airpower was more than a novelty, and it was obvious that further value would be forthcoming as technology improved. However, wartime experience had not validated airpower as a strategic element separate from the ground force. Mitchell and his disciples would have to argue their case with logic and peacetime demonstrations.
The US was back in the air, having broken its prewar lethargy in aviation. The nation was not ready to follow Britain and establish the Air Force as a separate military service, but the Army Reorganization Act of 1920 did recognize the Air Service as a combatant branch of the arm, on an organizational par with the Infantry and Artillery. The long climb toward an independent Air Force had begun.
Principal Aircraft of the Army Air Service
Breguet 14 (French). B-2 variant was France’s workhorse bomber. Also came in a reconnaissance variant (A-2). B-2 variant had clear panel “windows” on sides of observer’s cockpit.
Curtiss JN-4 Jenny (US) trainer. Most famous American airplane of the war. Trained 95 percent of all US and Canadian pilots. Engines not powerful enough for combat. Mainstay of barnstorming aviators of 1920s.
DeHavilland DH-4 (British/US) reconnaissance-bomber. Built on license in the United States using the American “Liberty” engine. Only US-built airplane to see combat. The Air Service preferred the Breguet for bombing and the Salmson for observation.
Nieuport 28 (French). The AEF’s first pursuit fighter. Despite design flaws, effective against German Albatros and Pfalz, but outclassed by Fokker D.VII.
Salmson 2A2 (French). AEF’s main reconnaissance airplane. Also employed as a bomber.
Sopwith F-1 Camel (British), so called because of the humped fairing over the nose guns. Pursuit fighter, highly maneuverable but comparatively slow. More aerial victories (1,294) than any other Allied aircraft of the war.
Spad XIII (French). Best Allied fighter of the war, matching the best German fighter, the Fokker D.VII. Fast, superb speed in the dive. The airplane of aces Frank Luke Jr. and Eddie Rickenbacker.
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