List of United States Army National Guard Observation Squadrons

United States Army National Guard units began forming Aerial Observation units before World War I. When the United States entered the war in April 1917, about 100 National Guard pilots joined the Aviation Section, U.S. Signal Corps (Later Air Service, United States Army).

After the demobilization of the World War I Air Service in 1919, in 1920, the Militia Bureau and the Air Service agreed on forming postwar National Guard aviation units. On 17 January 1921 the 109th Observation Squadron of the Minnesota National Guard became the first postwar air unit to receive federal recognition. They flew a wide variety of aircraft during the inter-war period. These included the Curtiss JN-4 "Jenny", Consolidated PT-1 "Trusty", Consolidated PT-3, Northrop BT-1, Douglas O-2 and Consolidated O-17 Courier during 1923-1931; the Douglas O-38 during 1931-1935; and the Douglas O-43 and North American O-47 between 1935 and 1942.

These 29 squadrons (18 of them having a World War I lineage and histories) formed by the Army before World War II remain active Air National Guard units today and are the direct predecessors of today's current units.

* Note: The "Federal Recognition" date is the effective date the unit was recognized for National Guard Service. Demobilized World War I Air Service units were re-established and re-designated effective that date.

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