English: The de Havilland DH-4 in the NASM collection was the first American-built version of Geoffrey de Havilland's famous British World War I bomber. Although the museum's specimen did not see action during the war, it was a test aircraft for what was to become America's first bomber and the only American-built aircraft to serve with the U.S. Army Air Service in the First World War.

When the United States entered the conflict on April 6, 1917, the Aviation Section of the Signal Corps did not possess any combat-worthy aircraft. So that a viable air arm could be created in the shortest possible time, a commission was established under the direction of Colonel R.C. Bolling to study current Allied aircraft designs being used at the front and to arrange for their manufacture in America.

Several European aircraft were considered, including the French Spad XIII, the Italian Caproni bomber, and the British SE-5, Bristol Fighter, and DH-4. The 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. Still, considerable engineering changes from the original British design were required to apply U.S. mass production methods. collections.nasm.si.edu/code/emuseum.asp?profile=objects&...