Fokker D.VIII

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Fokker D.VIII in Dutch markings

The Fokker D.VIII (also E.V) was a late World War I parasol-monoplane fighter aircraft designed by Reinhold Platz at the Fokker company. Dubbed the Flying Razor by Allied pilots, it had the distinction of scoring the last aerial victory of the war, but was otherwise better known for three lethal accidents due to wing failures.

In eary 1918, Fokker produced several rotary-powered monoplane designs. Of these, Fokker submitted the V.26 and V.28, small parasol-winged monoplanes with his usual steel-tube fuselages, for the second fighter trials at Adlershof. The V.28 mounted either the 145 hp Oberursel UR.III or 160 hp Goebel Goe.III, but both of these engines were in extremely short supply. The V.26 was powered by the relatively weak 110 hp Oberursel UR.II engine, but the design's low drag meant it could nevertheless keep up with some of the fastest of the Allied designs. In the end, the V.26 was ordered into production as the Fokker E.V. The Fokker designs were only barely beaten by the Siemens-Schuckert D.III with the complex bi-rotary Siemens-Halske Sh.III engine. The Siemens-Schuckert was put into production as well.

The D.VIII had an exceptional rate of climb, able to reach 6000 meters in 16 minutes. It was also highly maneuverable, although not to the same degree as the Siemens-Schuckert. Perhaps most importantly it was also considered to cost "less man-hours to build than any other WWI aircraft" according to Platz. Four hundered were ordered immediately with either the UR.III or Goe.III, but neither engine was available in any quantity and the production examples all mounted the UR.II.

The first production examples of the E.V were shipped to Jagdstaffel 6 in late July and soon were in operation. Emil Rolff scored the first kill in an E.V on August 17, 1918, but two days later he was killed when the wing delaminated in flight. Two more planes would be lost over the next two weeks, and on August 24 the design was removed from service. This was the third Fokker design to suffer wing failures, and Fokker soon initiated a study to finally get to the bottom of the matter. According to Fokker's autobiography, the wing's center of flexure lay too far behind the center of pressure which allowed a dangerous aeroelastic phenomenon, divergence, to occur. The solution was to reduce the section (and consequently, the stiffness), of the aft wing spar, thus moving the center of flexure forward and closer to the center of pressure.

According to most other accounts, the source of the wing failures lay in shoddy and rushed construction. The E.V wing spars made by the "Gebruder Perzina" (Perzina Brothers) woodworking factory for Fokker-and the "spar caps" of the E.V's wingspars (the sections of the wing spars that formed the top and bottom of each spar "box") had been placed too far apart during the fabrication of the unfinished wing spars at the Perzina plant-so that when the time came to shape the wingspars to their final form to be assembled into the cantilever wing, the spar cap sections had too much material removed from them, and resultingly had too little cross-sectional area for proper stiffness, and not enough strength to withstand combat maneuvers.

Production resumed in October after being renamed the D.VIII. Henceforth, the "E." and "Dr." designations were abolished, and all fighters received the "D." designation. The first new examples of the D. VIII started arriving at front line units late that month and started operations on the 24th. By the Armistice, 85 examples had been delivered.

A total of 289 aircraft were produced, and some served in the post-war era. Eight (four according to other sources) E.Vs from the Polish Air Forces operated against Soviet forces in the Polish-Soviet War of 1919-20. One of these planes was captured by the Red Army and used by the Soviets until the mid-1920s. Some planes reached Holland, Italy, Japan, the United States, and England as trophies, but most were scrapped in accordance with the terms of the Armistice. Today, the fuselage of one D.VIII has been preserved at the Caproni Museum in Trento, Italy.