De Havilland DH-4, 1917-1918. Creator: Dayton-Wright Company.

Two-seat, single-engine World War I biplane observation and bomber aircraft; 400-horsepower Liberty V-12 water-cooled engine. American-built version of a British design. Wings and tail natural finish overall. Fuselage light yellow on sides, brown on top. The United States possessed no combat-worthy aircraft upon entry into World War I in 1917. Several European aircraft were considered. The British DH-4 was selected because of its comparatively simple construction and its apparent adaptability to mass production. It was also well-suited to the new American 400-horsepower Liberty V-12 engine. American-built DH-4s were dubbed the "Liberty Plane." By war's end, 13 Army Air Service squadrons, five of them bomber squadrons, were equipped with them. In addition, four combined Navy-Marine squadrons were flying DH-4s along the Belgian coast.