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. Of the 4,346 DH-4s built in the United States, 1,213 were delivered to France, but of those only 696 reached the Zone of Advance. In the postwar period, the DH-4 was the principal aircraft used by the U.S. Government when air mail service began in 1918.
The DH-4 in the NASM collection was the prototype American-built DH-4, manufactured by the Dayton-Wright Airplane Company. This airplane was used in more than 2,600 experiments until its retirement in April 1919. It was also the airplane in which Orville Wright made his last flight as a pilot in 1918.
Transferred from the U.S. War Department, Bureau of Aircraft Production
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 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.
American-built DH-4s had some initial problems. The pilot and observer found themselves separated by the 254-liter (67-gallon) main fuel tank. This dangerous feature not only made communication between the crew members difficult, but it was hazardous in a crash. The much-touted Liberty engine was also at first a cause for concern. The prototype was designed and built in only six weeks. Not surprisingly, they too had technical problems. Once resolved, however, with a maximum speed of 198 kph (124 mph), the Liberty-powered DH-4 was able to match or even surpass the speed of most of the fighters of the time.
After completing trials in October 1917, production contracts were placed for the DH-4. It was dubbed the "Liberty Plane." By the end of the war on November 11, 1918, three U.S. manufacturers were building them. The largest producer was the Dayton-Wright Airplane Company of Dayton, Ohio, which built 3,106 airplanes. The Fisher Body Division of General Motors Corporation of Cleveland, Ohio, produced 1,600 aircraft, and the Standard Aircraft Corporation of Patterson, New Jersey, built 140 machines. Plans were under way to produce an additional 7,502 DH-4s, but orders were cancelled after the armistice.
The first American-built DH-4 reached France on May 11, 1918. However, because the arriving airplanes were not combat ready and required further preparation, the first mission was not flown until August 2. By war's end, thirteen Army Air Service squadrons, five of them bomber squadrons, were equipped with the Liberty Plane. In addition, four combined Navy-Marine squadrons were flying DH-4s along the Belgian coast. Of the 4,346 DH-4s built in the United States, 1,213 were delivered to France, and of those only 696 reached the Zone of Advance.
Although the American Liberty-engined DH-4s were in combat for less than four months, they proved their worth. Of the six Medals of Honor awarded to aviators during the First World War, four were received by pilots and observers flying DH-4s. Two were given posthumously to Lieutenant Harold Goettler and Second Lieutenant Erwin Bleckley of the 50th Aero Squadron. On October 8, 1918, they flew repeated missions over enemy lines to drop much-needed supplies to the survivors of the "Lost Battalion" of the 77th Division. At the cost of their lives, they accomplished the first successful American combat airlift operation. The other Medal of Honor recipients who flew in the DH-4 were Second Lieutenant Ralf Talbot and Gunnery Sgt. Robert Robinson of the First Marine Aviation Force.
The DH-4 continued in military service for many years after the war. The U.S. Army Air Service, later Army Air Corps, operated them until 1932. This was partly because many that were intended to be sent to Europe for the planned spring offensives of 1919 remained in the United States.
In the postwar period, the DH-4 demonstrated its versatility. It was the principal aircraft used by the U.S. Government when air mail service began in 1918. The L.W.F. (Lowe-Willard-Fowler) Company of College Point, New York, converted DH-4s to single-seat DH-4B mailplanes, with a compartment for 225 kg (496 lb) of mail replacing the front seat. For night flying, special flame-supressing exhaust stacks were fitted to prevent night blindness. The rugged DH-4 proved to be ideally suited for the task of delivering mail throughout the United States. Altogether, more than 200 of these DH-4Bs were used in a pioneering role by the U.S. Post office over a period of eight years. After 1927, a number of air mail DH-4s were modified or rebuilt as forest fire patrol aircraft to fly long-range patrols over the expansive western wilderness. A few were transferred to the new airlines that took over the mail services in 1926-1930.
Beyond these government applications, innovative private pilots adopted the DH-4 for various purposes when large numbers of them became available as government surplus in the 1920s. They were used as crop dusters, as early transport aircraft and air ambulances, and they were flown by barnstormers at county fairs.
The DH-4 in the NASM collection was built in Dayton, Ohio, by the Dayton-Wright Airplane Company. It was completed and flown on October 29, 1917. This was the prototype American-built DH-4. This airplane was used in more than 2,600 experiments, including engine, propeller, and control tests, until its retirement in April 1919. It was also the airplane in which Orville Wright made his last flight as a pilot in 1918.
The museum's DH-4 carries the complete military equipment used on American DH-4s in World War I: six 11 kg (25 lb) Mark II bombs, two DeRam DR-4 cameras, a wireless transmitter, and two Holt wing-tip flare holders. Defensive armament consists of two fixed, forward-firing .30-caliber Marlin machine guns, and the observer's position is armed with two flexible .30-caliber Lewis machine guns on a Scarff ring mount.
The War Department transferred the NASM DH-4 to the Smithsonian Institution in 1919. The National Air and Space Museum restored the aircraft in 1980-1981.