Fokker Parasol-Wing Fighters

[Jemiba]

... The US F VI seems to have been derived from the V 41 (which acted as prototype for the D.X fighter). ...

In "Fokker Flugzeugwerke" the V 41 is mentioned as "listed in a Fokker type list, compiled after the war, as a biplane with
N-struts and a 185 hp BMW engine, so maybe a two-seat variant of the D VII. ... there were several two-seat modifications
of the D VII, if they got V-numbers is unknown today ..."

 

[Apophenia]

Jens: That matches what I have for the V 41 as well. Construction begun in Germany with a 185 hp BMW IIIa as the planned powerplant. That V 41 airframe was shipped to the Netherlands and finally completed in 1921 with a 300 hp HS 8Fb engine.

One 2-seat D VII conversion that seems to have received a V-number was the V 31 glider tug. Claims that the V 35 and/or V 36 were also 2-seat D.VII developments seem less credible to me.

Thijs Postma in his Fokker - bouwer van de wereldluchtvaart, Fokker b.v. 1979, writes that the F.6 (PW.5) was a development of the V.37 armoured 'trench fighter' of 1918.

Arjen: If Postma is correct, that give the F VI a very interesting lineage! Conceptually, the V 37 was an armoured derivative of the V 28 but the V 37 itself was created from the unfinished airframe of the rotary-engined V 27

 

[Arjen]

Weyl has more information about the V.27 -> V-37 -> F.6 (PW.5) and the V.29 -> V.41 -> D.X lines. According to Weyl, the F.6 preceded the V.41, and the V.37 was the V.27 renamed after adding armour - V.27/37 powered by liquid-cooled engine(s).

 

[Apophenia]

... V.27/37 powered by liquid-cooled engine(s).

Thanks Arjen. I was confusing matter even further by conflating the V 26 with the V 27 :-[

 

[Arjen]

I'm trying to piece together from my books in what order the parasol-winged Fokkers appeared, and how they were related. With pictures Watch this space.

 

[Arjen]

The Fokker parasol-wing fighters started with the rotary powered V.26, prototype of the E.V/D.VIII, described by Weyl as "more or less a V.13 [1918 D.VI prototype] with the bottom wing removed". The V.28 was very similar, but strengthened to use rotaries of up to twice the power of the V.26's Le Rhône. Three inline-engined were also built: V.27, V29 and V.30. The V.29 was slightly larger than the V.26/28, the V.27 slightly larger and heavier again than the V.29. I have found no image or description of the V.30 other than a line in The Complete Book of Fighters by William Green & Gordon Swanborough:

This[V.28], initially flown with a 110 hp Oberursel Ur II, was also tested with the 145 hp Ur III and 160 hp Goebel Goe III 11-cylinder rotaries. Similar airframes with different engines were the 110 hp Le Rhône-powered V 26, the V 27 and V 30 with the 195 hp Benz Bz IIIb and IIIa six-cylinder water-cooled engines respectively, and the V 29 with the 160 hp Mercedes D III.

The V.30 designation was reused for a V.26-based glider. Weyl writes the V.30 glider was originally meant to be a flying bomb.
The V.27 was modified when Fokker learned the German Army wanted an armoured single-seater for ground-attack and the protection of infantry support aircraft. As well as adding side armour, Fokker's chief designer, Reinhold Platz, added a hollow armoured spinner to protect the V.27's radiator. To cool the engine, six radial blades were attached to the spinner's armour plate to drive cooling air through the radiator. This worked so well, that Fokker wanted to use it on a new interceptor fighter that needed no armour. The modified V.27 was renamed V.37. Thijs Postma in his Fokker - bouwer van de wereldluchtvaart, Fokker b.v. 1979, writes that the F.6 (PW-5) was a development of the V.37. Green and Swanborough write that the F.6 (PW-5) was Fokker's first post-World War I fighter. To confuse matters even more, the V.40 designation was reused for what became the F.6 - V.40 was previously used for a sport plane prototype.
Weyl writes the V.41 was a development of the V.29. Construction of the V.41 was started in 1921 in Schwerin, Germany, but the aircraft was shipped to Amsterdam for completion. In Amsterdam, it was renamed D.X.

V.13, V.26, V.27, V.28, V.29, V.37 images from Fokker Aircraft of World War I by Paul Leaman, Crowood 2001.
PW-5 and D.X images from Fokker: The Creative Years by A.R. Weyl.

 

[Arjen]

3-view drawings from Fokker: The Creative Years

 

[Arjen]

Confusion reigns. Theo Wesselink, in Nederlandse vliegtuigen - Deel 1 - Nederlandse vliegtuigbouwers in het buitenland, writes the V.41 was a two-seat D.VII. In Nederlandse vliegtuigen - Deel 2 - Alle vliegtuigen ooit gebouwd in Nederland, Wesselink describes the D.X as a short-fuselage development of the PW-5.

 

[Jemiba]

Title changed for more clarity, thank you, Arjen !

 

[Anachronus]

Fokker was excellent at variations on a theme. Many of them were gorgeous aircraft that it is a pity never worked out as planned.

 

[Airborne2001]

Does anyone have any performance specs of the Fokker V.29?

 

[hesham]

Does anyone have any performance specs of the Fokker V.29?

Small Info.

 

[Tuizentfloot]

From Fokker Flugzeugwerke in Deutschland 1912-1921 by P.M. Grosz and V. Koos (2004), p. 117, with referece to Werksangaben.

 

[riggerrob]

Fascinating!
We wonder how much Fokker's wide cabane struts compared with more traditional narrow cabanes (e.g. meet at center line) plus lift struts in terms of weight and strength.