de Havilland DH-4 (U.S. Air Mail)

The aircraft labeled 'Fokker DH-4 Mail' is the American-built de Havilland DH-4, the standard airplane of the U.S. Post Office Air Mail Service in the early 1920s. Originally a British Airco/de Havilland DH.4 day bomber of World War I, it was mass-produced in the United States with the American Liberty L-12 engine in place of the British Rolls-Royce Eagle, by firms including Dayton-Wright and Boeing. After the war, surplus DH-4s were extensively rebuilt for mail duty: the cockpit was moved aft behind a forward mail and fuel compartment, and many received welded steel-tube fuselages (DH-4B/DH-4M).

It was the workhorse that established scheduled and later transcontinental air mail across the country. The 'Fokker' attribution in the label is incorrect; the DH-4 was a de Havilland design, not a Fokker product.