Douglas YO-31B

Photograph of a United States Army Air Corps Douglas YO-31B aircraft parked by a hangar, likely at the National Air Races in Ohio, circa 1930s.

Inscription: "U.S. Army. Douglas YO-31B."

Inscription on verso: "Douglas O-31B. Conqueror G1-1570-C, 600 H.P. A2CLM. J-31."

Item from page 34 of the LeRoy Milliren National Air Races photograph album, circa 1920s-1930s. Album contains one hundred ninety-eight (198) black-and-white photographs taken at the air races during this time period.