The 186th Aero Squadron was a United States Army Air Service unit that fought on the Western Front during World War I.
The squadron was assigned as an Army Observation Squadron, performing long-range, strategic reconnaissance over the entire length of the United States First Army sector of the Western Front in France. After the 1918 Armistice with Germany, the squadron was assigned to the United States Third Army, VII Corps Observation Group at Trier Airfield, Germany as part of the Allied Occupation of the Rhineland.
The squadron was demobilized in Germany during July 1919 and its members returned to the United States. There is no modern United States Air Force unit that shares its lineage and history.
The squadron was formed at Kelly Field, Texas, on or about 16 November 1917. It consisted of forty men transferred from the 25th Aero Squadron and 110 previously unassigned recruits from Kelly Field No. #1. The first official duty of the 186th was operation at the flying school where it was organized. From November 1917 to 20 January 1918 the 186th operated at the flying school there at Kelly Field, flying Curtiss JN-4 trainers and learning the basics of flying. With its initial training completed, the squadron was ordered on 20 January to proceed to the Aviation Concentration Center, Camp Mills, Garden City, New York, from which it would proceed overseas for duty.
The transportation of the squadron from Kelly Field to Camp Mills was accomplished with some good humor, much complaining, a few drunks, a minor accident or two, a few stray kisses administered to the men from patriotic American girls who desired to help make the world "free for democracy", but there were no casualties. The train jumped the track at Basile, Louisiana, which gave the men a chance to sample some good Southern liquor. One man was placed under arrest for disorderly conduct. At Washington, D.C., the Red Cross ladies served sandwiches and coffee, but no liquor. No arrests were made.
The 186th arrived at Aviation Concentration and Supply Camp No.