Fokker D.VII

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Fokker D.VII

Type	Fighter
Manufacturer	Fokker-Flugzeugwerke
Designed by	Reinhold Platz
Maiden flight	January 1918
Primary user	Luftstreitkräfte
Produced	1918
Number built	approximately 1700

The Fokker D.VII was a late World War I fighter aircraft designed by Reinhold Platz of the Fokker-Flugzeugwerke. When introduced into combat in 1918, it quickly proved to be superior to existing Allied fighters, leading to a second Fokker Scourge. The D.VII was the only weapon specifically mentioned by name in the armistice agreements at the end of the war (Surrender in good condition by the German Armies of [...] all aircraft of the D7 type [...]).

1 Development and production
2 Combat debut
3 Postwar service
4 Operators
5 Specifications (Fokker D.VII)
6 References
7 External links
8 Related content

[edit] Development and production

Fokker D.VII preserved in the Deutsches Museum

Fokker D.VII

Fokker's chief designer Reinhold Platz had been working on a series of experimental planes, the V-series, since 1916. These planes were characterized by the use of thick-sectioned, cantilever wings (based on his German government-required collaboration with Hugo Junkers, who originated the idea in 1915 with his own firm and with the earliest all-metal aircraft) instead of thin wings with external wire bracing. This resulted in a stronger wing with greater lift and more docile stalling behavior.

Late in 1917, Fokker built the V.11 experimental biplane, fitted with the standard Mercedes D.IIIa engine. In January 1918, a competition to select a new fighter was held at Adlershof. For the first time, frontline pilots would directly participate in the evaluation and selection of new fighters. Fokker sent in the V.11 along with several other prototypes. Manfred von Richthofen flew the V.11 and found it tricky, unpleasant, and directionally unstable in a dive. In response to these complaints, Fokker modified the V.11 by lengthening the fuselage and adding a fixed fin in front of the rudder. Upon flying the modified V.11, Richthofen praised it as the best aircraft of the Adlershof competition. It offered excellent performance from the outdated Mercedes engine, yet it was safe and easy to fly. Richthofen's recommendation virtually decided the competition, but he was not alone in recommending it. Fokker immediately received a provisional order for 400 V.11 aircraft.

Fokker's factory was not up to the task of supplying the entire air force, so their rivals at Albatros and AEG were directed to build the D.VII under license, though AEG did not ultimately produce any aircraft. Fokker did not use production plans for their designs, instead building directly from jigs, and so they simply sent a completed D.VII to Albatros to copy. Albatros paid Fokker a 5 percent royalty for every D.VII built under license. Albatros Flugzeugwerke and its subsidiary, Ostdeutsche Albatros Werke (OAW), built the D.VII at factories in Johannisthal and Schneidemühl, respectively. The former carried the designation Fokker D.VII (Alb), while those constructed at Schneidemühl were designated Fokker D.VII (OAW). Some parts were not interchangeable between aircraft produced at different factories, even between Albatros and OAW.

Albatros soon surpassed Fokker in the quantity and quality of aircraft produced. The state of German industry had already started to deteriorate at this point, and under 2,000 of the planes were delivered from all three plants, with the most commonly quoted figure being 1,700.

[edit] Combat debut

Hermann Goering's Fokker D.VII(F) (serial 5125/18)

Fokker D.VII of Jasta 66

The D.VII entered squadron service with Jasta 10 in early May 1918. The plane quickly proved to be vastly superior to the existing Albatros and Pfalz scouts. Unlike the Albatros scouts, the D.VII could dive without any fear of structural failure. The D.VII was also noted for its ability to climb at high angles of attack, its remarkably docile stalling behavior, and its reluctance to spin. These handling characteristics contrasted with contemporary scouts such as the Camel and SPAD, which stalled sharply and spun vigorously.

However, the D.VII also had problems. Heat from the engine often ignited phosphorus ammunition until cooling vents were installed in the ammunition cans. Fuel tanks sometimes broke at the seams. The D.VII also shed fabric and experienced rib failures on the upper wing. Planes built by the Fokker plant at Schwerin were particularly noted for their lower standard of workmanship and materials. Nevertheless, the D.VII proved to be a remarkably successful design, leading to the familiar aphorism that it could turn a mediocre pilot into a good one, and a good pilot into an ace.

Production D.VII aircraft initially used the 180 hp Mercedes D.IIIa, followed by the high-compression 200 hp Mercedes D.IIIaü. Modern sources, however, commonly refer to these engines under the generic designation of "160 hp Mercedes D.III." The D.VII was significantly improved by mounting the "overcompressed" 185 hp BMW IIIa, a development of the old Mercedes engine that combined increased displacement, higher compression, and an alititude-adjusting carburetor to markedly increase speed and climb at high altitude. Because the BMW IIIa was "overcompressed," using full throttle at altitudes below 2,000 meters risked detonation and damage to the engine. In an emergency, however, using full throttle at low altitudes could produce up to 240 hp.

Planes with the new BMW engine were designated D.VII(F). The first entered service with Jasta 11 in late June 1918. While pilots clamored for the D.VII(F), production of the BMW engine was very limited and the D.VII continued to be produced with the 180 hp Mercedes D.IIIaü until the end of the war.

Manfred von Richthofen died only days before the plane was introduced and never flew it in combat. Other pilots, including Hermann Göring, quickly racked up victories and generally lauded the design. Supplies were limited at first, but by July there were 407 on charge. Larger numbers were available by August, when they achieved 565 victories. The D.VII eventually equipped 46 Jagdstaffeln. When the war ended in November, 775 D.VII aircraft were in service.

[edit] Postwar service

Interned Fokker D.VII in Swiss markings

Postwar, the D.VII saw extensive use in the United States, where 142 captured examples were evaluated. The D.VII also served in the Polish (around 50), Dutch, Swiss, and Belgian air forces. It was the most numerous Polish fighter of the Polish-Soviet War. The D.VII proved to be so popular that Fokker completed and sold a large number of D.VII airframes that he had smuggled into the Netherlands after the Armistice. As late as 1929, the Alfred Comte company manufactured eight new D.VII fighters under licence for the Swiss Fliegertruppe.

Today, preserved aircraft can be found in the Militaire Luchtvaart Museum (The Netherlands), the Brome County Historical Society (Canada), whose aircraft is believed to be the most original surviving example (and has possibly been reported as being for sale as of late 2006) , the National Aviation Museum (Canada), the Deutsches Museum (Germany), the Royal Air Force Museum (United Kingdom), the Musée de l'Air (France), and the National Air And Space Museum.