Pfalz D.III

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Pfalz D.III

Type	Fighter
Manufacturer	Pfalz Flugzeugwerke
Designed by	Rudolph Geringer
Maiden flight	April 1917
Primary user	Luftstreitkräfte
Produced	1917 to 1918
Number built	approximately 1075

Pfalz D.III prototype in April 1917

The Pfalz D.III was a World War I fighter aircraft, the first major original design from Pfalz Flugzeugwerke. The D.III was widely used by German fighter units from the fall of 1917 until the end of the war.

1 Development
2 Operational use
3 Specifications
4 References

[edit] Development

The Eversbusch brothers formed Pfalz Flugzeugwerke with the intention of building aircraft under license. Prior to World War I, they built several Morane-Saulnier monoplane designs under license, which entered military service as the Pfalz E series. As the war progressed, Pfalz turned to designs from Roland, notably the Roland D.I and Roland D.II.

In April 1917, Pfalz's chief engineer, Rudolph Gehringer, produced an original fighter design. The resulting D.III looked very similar to the earlier Roland design due to the fish-like shape of the fuselage. Like the Rolands, the D.III used a plywood monocoque fuselage. Two layers of veneer strips were spirally wrapped in opposing directions over a mold to form one half of a fuselage shell. The fuselage halves were then glued together, covered with a layer of fabric, and doped. This Wickelrumpf method gave the fuselage great strength and smooth contours compared to conventional construction techniques, but it was much more labor intensive. Furthermore, the D.III fuselage was prone to twisting or warping from side to side as it aged, a defect variously attributed to the use of insufficiently seasoned wood, or to moisture absorption in damp conditions. This caused the aircraft to pull to one side, resulting in many landing accidents.

The wings were of conventional construction, while the ailerons were, unusually, of wooden construction. The horizontal stabilizer had an inverted airfoil section, which made it easier to pull out of dives and permitted the use of an unbalanced elevator. Like the Albatros, the Pfalz D.III featured a flush Teeves and Braun radiator buried in the upper wing, offset to the right of the pilot, providing cooling for the 170 hp Mercedes D.III engine.

[edit] Operational use

Pfalz D.III (serial 4114/17) of Marine Feld Jasta II

Pfalz D.IIIa (serial 8413/17) displaying hastily applied Balkenkreuz markings

The prototype D.III first flew in May 1917. Deliveries to operational units, mostly Bavarian Jastas, began in August. While markedly better than the earlier Roland designs, the D.III was generally considered inferior to the Albatros D.III and D.V. Contemporary pilot accounts variously criticized the Pfalz's heavy controls, lack of speed, lack of power, or lack of climb compared to the Albatros. The Pfalz also stalled sharply and spun readily. Recovery from the resulting flat spin was difficult. The D.III also slipped in turns. However, a British flight test report of a captured Pfalz D.III (serial 4184/17) praised its handling characteristics and stated that it answered the controls better than the Albatros.

Unlike the Albatros, the Pfalz was structurally sound. The Albatros scouts were plagued by failure of their single-spar lower wings, a design that had been forced on Albatros by the Idflieg. The Pfalz, however, could safely dive at high speeds due to its sturdy, twin-spar lower wing. Pilots who were leary of the Albatros scouts therefore gravitated to the Pfalz. For the same reason, the Pfalz was a favorite for shooting down observation balloons, which were heavily defended with anti-aircraft guns trained to the balloon's altitude. Attacking a balloon was generally attempted by approaching at a higher altitude, and then diving on it at high speed to give the guns as little time to fire as possible.

The only major complaint among the pilots who used it in this role was that the machine guns were buried in the forward fuselage, making it impossible to clear jams in-flight. This led to the slightly modified D.IIIa, which moved the guns to the upper decking. The D.IIIa was distinguishable by its enlarged semicircular horizontal stabilizer. The D.IIIa further featured cropped lower wingtips and a more powerful Mercedes engine. The D.IIIa entered service in November 1917. An experimental triplane version of the D.III was built, but it yielded inferior performance and handling.

About 300 Pfalz D.III and 775 D.IIIa scouts were built in total. When the final batch was completed in April 1918, production shifted to the D.IIIa's successor, the Pfalz D.XII. As of June 1918, about 430 D.IIIa scouts were still in service. By August, that number had declined to 166, and most examples had been withdrawn from frontline units. Today, there are no known surviving examples.