Pfalz D.XII

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Pfalz D.XII

The Pfalz D.XII was a World War I fighter aircraft from Pfalz Flugzeugwerke. It entered service in significant numbers near the end of the war, alongside the more renowned Fokker D.VII.

In early 1918, the Idflieg (Inspektion der Fliegertruppen) distributed to German aircraft manufacturers a detailed engineering report of the SPAD S.VII, which the Idflieg considered to have a particularly sound wing design. Pfalz accordingly produced several Pfalz D.III-derived prototypes with SPAD-type wings. These developed into the Pfalz D.XII. Like the D.III, it featured the Mercedes D.III engine, although in this case the more powerful 180 hp D.IIIaü version. The D.XII continued Pfalz's Wickelrumpf plywood-skinned monocoque fuselage construction, introduced in the Pfalz D.III. Unlike the D.III, the D.XII used a two-bay wing cellule. Furthermore, the flush wing radiator was replaced with a car-type radiator mounted in front of the engine. The prototype first flew in March 1918, and a limited run of 50 was ordered.

Several D.XII prototypes were entered in the second fighter competition at Adlershof in May/June 1918, where it competed against the Fokker D.VII. In "Fokker: The Creative Years," A.R. Weyl wrote that only Ernst Udet favored the D.XII over the Fokker D.VII, but Udet's opinion carried such weight that Pfalz received substantial production orders for the D.XII. The official type test was on June 19, 1918.

Difficulties with the radiator, which used vertical tubes rather than the more common honeycomb structure, delayed initial deliveries until June. The first 200 production examples could be distinguished by their rectangular fin and rudder. Subsequent aircraft featured a larger, rounded rudder profile.

The D.XII began reaching the Jagdstaffeln, primarily Bavarian units, in July 1918. Units in quieter sectors of the front were completely equipped with the D.XII. While the D.XII was a marked improvement over the obsolescent Albatros D.V and Pfalz D.III, it nevertheless found little favor with German pilots, who strongly preferred the Fokker D.VII. In his book "Wings of War," Leutnant Rudolf Stark, commander of Jasta 35, wrote:

Every pilot climbed into the new machine with pre-conceived notions and immediately voiced all manner of complaints. No one wanted to fly the Pfalz on his own accord, and those who were assigned the D.XII were reluctant to fly the machine. Later on pilots did all right with the D.XII. In fact, it climbed well and could fly along with the Fokker D.VII in all respects, and in a dive it was a bit faster. But in turns and combat it was slow and could not compare with the Fokkers. The Pfalz was a sluggish work horse which fought the bridle and had to be controlled with a strong halter.

Thanks to its sturdy wing and thin airfoil section, the D.XII maintained the excellent high-speed dive characteristics of the earlier Pfalz D.III. Like most scouts of the era, however, the D.XII had an abrupt stall and a pronounced tendency to spin. Furthermore, contemporary pilot accouts consistently criticized the D.XII for its long takeoff run and "clumsy" handling qualities in the air. Rate of roll, in particular, appears to have been deficient. Landing was also tricky because the D.XII tended to float above the ground, and the landing gear was weak. Ground crews disliked the extensive wire bracing that accompanied the two-bay wing.

Between 750 and 800 D.XII scouts had been completed by the Armistice. A substantial number, perhaps as many as 175, were surrendered to the Allies. The D.XII's only lasting claim to fame is that two were purchased by an American buyer after the war, and were later to appear in the films Hell's Angels and the first Dawn Patrol. One of these later made its way to the National Air and Space Museum, while the other was acquired by the Champlin Fighter Museum, itself now part of the Seattle Museum of Flight. Other preserved aircraft are displayed at the Musée de l'Air in Paris and the Australian War Memorial in Canberra.

Pfalz also produced a derivative of the D.XII, the D.XIV. The D.XIV replaced the Mercedes D.IIIaü with the 200 hp Benz Bz.IVü, a substantially heavier engine. To cope with the increased power and weight, the D.XIV featured longer span wings and an enlarged vertical stabilizer. Only a few examples were built, and none saw operational service.