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Pfalz D.XII
Type	Fighter
Manufacturer	Pfalz Flugzeugwerke
Designed by	Rudolph Gehringer
Maiden flight	March 1918
Primary user	Luftstreitkräfte
Produced	1918
Number built	approximately 800

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.

Contents 1 Development 2 Operational use 3 Pfalz D.XIV 4 Specifications 5 References

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. Most units operated the D.XII in conjunction with other fighter types, but 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.Va and Pfalz D.IIIa, 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:

“

No one wanted to fly those Pfalzs except under compulsion, and those who had to made as much fuss as they could about practicing on them. Later their pilots go on very well with them. They flew quite decently and could always keep pace with the Fokkers; in fact they dived even faster. But they were heavy for turns and fighting purposes, in which respect they were not to be compared with the Fokkers. The Fokker was a bloodstock animal that answered to the slightest movement of the hand and could almost guess the rider's will in advance. The Pfalz was a clumsy cart-horse that went heavy in the reins and obeyed nothing but the most brutal force. Those who flew the Pfalzs did so because there were no other machines for them. But they always gazed enviously at the Fokkers and prayed for the quick chance of an exchange.

”

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 were difficult 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. Of these, a few were brought back to the United States and Canada for evaluation. Two D.XIIs were sold as war surplus to the Crawford Aeroplane & Supply Co. of Venice, California. These aircraft, which appeared in the films Hell's Angels and the first Dawn Patrol, are today preserved at the National Air and Space Museum and the Seattle Museum of Flight. Other preserved aircraft are displayed at the Musée de l'Air et de l'Espace 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 180 hp 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. A few prototypes were built and tested at the second Adlershof competition, but no production order ensued. The D.XIV did not offer an appreciable increase in performance over the D.XII, and the Benz Bz.IV engine was needed for reconnaisance aircraft.

General characteristics

• Crew: One
• Length: 21 ft (6.35 m)
• Wingspan: 29 ft 6 in (9.00 m)
• Height: 8 ft 10 in (2.70 m)
• Wing area: 233.6 ft² (21.70 m²)
• Max takeoff weight: 1,989 lb (902 kg)
• Powerplant: 1× Mercedes D.IIIaü , 180 hp (134 kW)

Performance

• Maximum speed: 106 mph (170 km/h)
• Service ceiling: 18,500 ft (5,640 m)

Armament

• 2x 7.92 mm LMG 08/15 "Spandau" machine guns

• Herris, J. Pfalz Aircraft of World War I (Great War Aircraft in Profile, Volume 4). 2001. ISBN 1-891268-15-5.

• Stark, R. Wings of War: A German Airman's Diary of the Last Year of the Great War. 1988. ISBN 0-947898-96-4.

• Weyl, A.R. Fokker: The Creative Years. 1988. ISBN 0-851778-17-8.