Fokker D.VIII

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Fokker D.VIII

Description
Role	Day fighter
Crew	one, pilot
Dimensions
Length	19 ft 4 in	5.86 m
Wingspan	27 ft 6.75 in	8.40 m
Height	9 ft 3 in	2.80 m
Wing area		10.70 m²
Weights
Empty
Maximum take-off	1,238 lb	562 kg
Powerplant
Engines	1x Oberursel Ur.II
Power	110 hp
Performance
Maximum speed	127 mph	204 km/h
Combat range
Ferry range
Service ceiling	20,670 ft	6300 m
Armament
Guns	2x 7.92mm Spandau machine guns
Bombs	none

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.

By late 1917 the industrial might of the Allies had been able to build air forces of such a size that the Germans were simply not able to maintain air superiority over the whole of the front. However their better pilots and planes meant that they could move their Jastas around the front to any location of interest and maintain control there. By January 1918 even this ability was lost when newer fighter designs from both British and French factories started entering service in massive numbers.

In response the German command held a contest for a new fighter design based on the 160hp Mercedes D.III engine. The clear winner of the contest was the Fokker D.VII, which was rushed into production. However the supplies of the Mercedes were limited, and with all designs moving to larger engines of this class, or even bigger, high command decided to hold another competition in April to choose another design for side-by-side production.

Among other designs, Fokker submitted the V.26 and V.28, small parasol-winged monoplanes with his usual steel-tube fuselages. The V.28 mounted either the 145hp Oberursel UR.III or 160hp Goebel Goe.III, but both of these engines were in extremely short supply. The V.26 was powered by the relatively weak 110hp 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. Platz felt the V.26 could compete with some of the newest fighters being offered by other designers. Fokker was just as interested in it, as it was perhaps the only new design that still used the Oberursel engine, a factory he had purchased in 1916.

A large number of aircraft were offered for the contest, from practically every current manufacturer and even a few hopefuls. The Fokker managed to beat them all, even though it was considered radically different from the other more conventional biplanes. In the end the V.26 was ordered into production as the Fokker E.V (E for Eindecker, monoplane). In both contests the Fokker designs had only barely beaten out competition from Siemens-Schuckert, and in this case the Siemens-Schuckert D.IV with the complex bi-rotary Siemens-Halske Sh.III engine was put into production as well.

The D.VIII had an exceptional rate of climb, able to reach 6000m 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. 400 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. 85 were eventually delivered by the end of the war three weeks later.

289 planes of this type were built in total, and some served in the post-war era. Eight (four according to other sources) E.Vs from the Polish Air Forces flew against Soviet forces in 1919 and 1920 war. 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 USA, and England as trophies, but the rest were scrapped in accordance with conditions set forth in the Armistice. Today, the fuselage of one D.VIII has been preserved at the Caproni Museum in Trento, Italy.