III Corps Observation Group The III Corps Observation Group was an Air Service , United States Army unit that fought on the Western Front during World War I as part of the Air Service , First United States Army . It was demobilized on 12 May 1919 . There is no modern United States Air Force unit that shares its lineage and history . History . First Army Air Service . The III Corps Observation Group was organized on 20 September 1918 by the First Army Air Service at Souilly Aerodrome , France . It was formed after the St . Mihiel Offensive and for the purpose of operations in the forthcoming Meuse - Argonne Offensive . It ' s units consisted of a Headquarters Squadron , the 90th Aero Squadron , the 88th Aero Squadron , the Aéronautique Militaire N . 284 Escadrille , the N . 205 Escadrille , Detachment 10 / 13 / 18 , and the 199th Park Squadron for logistics and transportation support . The first efforts of the Group were directed towards organization and preparation for combat operations in the coming offensive . To this end , the 88th and 90th were designated as Corps Observation Squadrons whose duty it would be to make artillery adjustments , to perform photographic missions of the Corps front , to make long distance reconnaissances and support the 90th and 28th French Infantry together with Divisional work . The 205th French Squadron did all Corps artillery adjustments requested . The divisions the Group for which work was done in the Meuse - Argonne Offensive were the 33d , 80th , 5th , 90th , 29th and 75th of First Army . The 88th was assigned to Corps Headquarters , the 90th for the Right and Left Divisions , with the French units being assigned to Corps Artillery and the Center division in the offensive . The 88th was required to keep an airplane constantly on reconnaissance patrol from dawn to dusk each day . This plane reported to the III Corps Commander , keeping him informed by wireless messages , and weighted messages from time to time with respect to the road movement of the enemy , general aspect of the sector , information on friendly and enemy troops , artillery and machine gun activity on each side and other important information for his attention . Also , information of particular interest to divisions would be reported to them . The mission of the 90th was to principally keep the divisional commander informed of the location of his own troops . The aircraft were also , when deemed appropriate communicate directly with Brigade Commanders , with the brigades establishing suitable message dropping locations along their line of march . The greatest attention by the Brigades were the manipulation of panels so the air service could render effective aid when called for . Also , the squadron was tasked to work with divisional artillery through squadron liaison officers . During the Meuse - Argonne Offensive , the Group Headquarters worked night and day directing the operations , coordinating the work , and suggesting and sending out missions carried out by the squadrons , which returned with valuable and complete information . The progress of the attack was followed the line taken at intervals during each day of the attack . In the first phase of the Offensive , in the Argonne - Meuse sector took place at Souilly , beginning the night of 26 October and continuing until 29 October when Headquarters and the squadrons moved to Bethelainville Aerodrome . The Group was well - equipped at the beginning of operations with excellent and capable Salmson 2A2 aircraft and outstanding personnel . Many of the planes were damaged during the attack due to enemy fire and the engines were constantly overworked . Towards the end of the offensive , the activity and aggressiveness of enemy aviation increased . A squadron with the planes painted red came into the sector on 15 October . This squadron was most aggressive and was said to be Richtofen ' s " Old Circus " . While engaged in combat operations , the Group also operated Infantry liaison schools without interference with work over the lines while at Souilly . Two infantry different detachments of 500 men , with about 50 non - commissioned officers and thirty - two commissioned officers came to the airfield , and were given a 5 - day course in work with airplanes . The III Corps Observation Group continued operations at Bethelainville until 11 November , at which time hostilities were suspended The Group had 53 days of combat operations , with a total of 1 , 146 sorties and a total of 1 , 111 combat hours and 3 minutes . The 90th Aero Squadron shot down 7 enemy aircraft and the 88th three . Twenty - five successful artillery adjustments were made by the observations performed by the group . Also Thousands of sheets of leaflets were dropped on enemy forces . Third Army Air Service . During the weeks following the signing of the Armistice , the III Corps Observation Group would be the advance corps in the Third Army ' s march to the Rhine River and the Occupation of the Rhineland . The Group was re - organized , being relieved from First Army and transferred to the Third Army Air Service on 21 November 1918 . The 88th Squadron which had been active in combat during the Meuse - Argonne Offensive was relieved and transferred to the Third Army VII Corps Observation Group . The 90th was transferred to the I Corps Observation Group , and remained in France for demobilization , along with a number of Headquarters personnel . The 1st Aero Squadron , the senior squadron in the American Air Service , was assigned to the Group for its operations with Third Army on the Rhine . Corps Air Service Headquarters was moved along with III Corps to the Rhine beginning on 11 November . It crossed from France into Luxembourg on 21 November , and into the German Rhineland on 1 December . It arrived at its assigned station , the former Deutsche Luftstreitkräfte ( German Air Force ) Weißenthurm Airdrome , on 21 November 1918 . During its period on the Rhine , the Group participated in all maneuvers of Divisions in the III Corps , and a school for infantry and artillery liaison was established . An extensive training program was organized in Aerial photography , infantry liaison , artillery adjustments , machine guns , infantry drill regulations , map reading and the study of photographs , lectures on the cooperation of aviation with the other branches of the Army . Practice flights included long - distance cross country , photographic missions , formation flying and also , the flying of German aircraft obtained and evaluation of their capabilities and other aspects of their construction . On 15 April 1919 , four additional squadrons were assigned to the Group from the demobilized First and Second Air services in France . These were the 24th , 138th , 168th and 256th . With these additional units , the aerodrome at Weißenthurm was expanded . Also plans were made by Third Army AS to place a main Supply Depot adjacent to the airfield at Weißenthurm . Between 23 and 27 April , the Group participated in the Third Army Horse - Motor and Aviation Show at Coblenz . The 1st Aero Squadron placed a Salmson 2A2 observation plane on display equipped for duty over the lines as well as an airplane stripped of its canvas showing its methods of construction . The 1st also won the Airplane photographic race competition , in which in 31 minutes the squadron took areal photos of a specified area and dropped developed and printed photos . The flight time from Coblenz to Weißenthurm was 31 minutes . The 1st also won honors in a message dropping contest , making a ground drop of written observation from an aircraft at 500m altitude 10 yards from a panel . It also displayed its Radio Section which showed the methods of liaison from ground to air and air to ground employed by the Air Service during the War . On 12 May 1919 orders were received from Third Army for all squadrons of the Group to report to the Services of Supply 1st Air Depot , at Colombey - les - Belles Airdrome to demobilize for immediate return to the United States . Personnel were subsequently assigned to the Commanding General , Services of Supply and ordered to report to a staging camp in France . There , personnel awaited scheduling to report to one of the Base Ports in France for transport to the United States and subsequent demobilization . The men of the III Corps Observation Group arrived in New York Harbor in mid July 1919 . There most of the men were demobilized and returned to civilian life .