Established in 1939 as a prewar bombardment squadron, it was equipped with a mixture of Douglas B-18 Bolo medium and early-model Boeing B-17 Flying Fortress heavy bombers.

After the outbreak of World War II in Europe it flew patrols over the Atlantic Coast searching for German U-boat activity.

Deployed to Borinquen Field, Puerto Rico in late 1940, the unit was assigned to the Caribbean Air Force, 25th Bombardment Group.

[3] With the Navy taking over the antisubmarine mission, the squadron moved to France Field, Canal Zone in December 1943, where it became an element of the VI Bomber Command.

The Squadron carried on patrols up and down the Atlantic coast of Panama and into neighboring Colombian waters until relieved from assignment to Sixth Air Force and returned to the United States.