A.Weyl Fokker: The Creative Years (Putnam)

The V.6 triplane

   In pursuit of his policy of developing parallel prototypes with rotary and stationary engines, Fokker wanted a triplane with a Mercedes engine. In this configuration the result was the V.6, which had a 120-h.p. Mercedes.
   Platz designed the V.6 to have approximately the same wing loading as the Fok. Dr.I, consequently its heavier engine inevitably made it a larger aircraft. Its wing span was something over 8 m. (26 ft. 6 in.). The greater chord of the mainplanes dictated larger gaps; this meant that the bottom wing had to be placed a short distance below the fuselage. Aerodynamically this was bad, for it caused interference drag, premature flow separation at the lower wing, and an extensive vortex region aft that reduced the effectiveness of the tail controls. As Fokker soon discovered, the performance and flying qualities were adversely affected.
   The lower centre section was later faired into the fuselage, adding considerably to the fuselage depth, but this did little good. The V.6 had other defects. The long six-cylinder engine made it necessary to place the cockpit well aft: owing to this and the larger wing chord, the pilot's view was inferior to that afforded by the Fok. Dr.I. Being a larger aircraft, the V.6 was less manoeuvrable. It was therefore a poor prospect, even if its aerodynamic deficiencies could have been remedied: it was and remained an ungainly aeroplane. Fokker saw no point in pursuing its development and abandoned the design.
   One feature of the V.6 that became a characteristic of later Fokker fighters with water-cooled engines was its nose radiator mounted immediately behind the airscrew. There was nothing new or original about the nose radiator, but it had been almost forgotten in Germany when Platz revived it in the V.6. For those days it was an excellent position for the radiator, and much to be preferred to the then-fashionable radiator installations in or at the wings, which were detrimental to the airflow over the wings.

J.Herris, T.Phillips Fokker Aircraft of WWI. Vol.4: V.1-V.8, F.I & Dr.I (A Centennial Perspective on Great War Airplanes 54)

Fokker V.6

  Developed in parallel with the rotary-powered V.5, the Fokker V.6 featured a 160 hp Mercedes
D.III six-cylinder, water-cooled engine. Ordered on 7 July 1917, the V.6 was a larger airplane than the V.5, which was necessary to retain a similar wing loading despite the heavier engine. Wing span, chord, and area were all increased.
  The greater chord compelled increased wing gap to avoid airflow interference between the wings. At first the bottom wing was mounted beneath the fuselage on short struts, but to reduce drag it was faired into the fuselage.
  The heavy V.6 lacked the excellent climb rate and sparkling maneuverability of the lighter, rotary-engine triplanes like the V.5 and development was dropped.


Fokker V.6 Specifications
Engine: 160 hp Mercedes D.III
Wing: Span Upper 7.90 m
Span Middle 6.60 m
Span Lower 6.00 m
Wing Area 22.5 m2
General: Length 5.75 m
Height 2.725 m
Empty Weight 637 kg
Loaded Weight 880 kg
Climb: 1000m 3 min
2000m 6.5 min
3000m 12 min
4000m 20 min
5000m 34 min
Armament: 2 mgs



Fokker V10

  The V10 was a design for a single-seat triplane fighter on floats powered by a 160 hp Mercedes D.III. The aircraft was commissioned from Fokker on 18 September 1917. Given w/n 1852, the aircraft was cancelled before completion in October because Fokker assessed the results of all triplanes with in-line engines as negative. The Navy wanted a land combat single-seater suitable for use in Flanders; the requirement was also referred to as the Channel task. Since reliable rotary engines of the 160 hp class were not yet available, Rolshoven considered the V6 triplane with Daimler D.III that was currently being tested, but the cooling problems and the unfavorable arrangement of the lower wing would have to be eliminated. Wing area was 22.5 or 21.4 m2; in comparison the lighter Dr.I had a wing area of 18.66 m2
  The operational success of the Brandenberg W12 two-seat floatplane fighter eliminated further interest in single-seat floatplane fighters.

O.Thetford, P.Gray German Aircraft of the First World War (Putnam)

Fokker V 6
   Yet another variation of the triplane theme in the summer of 1917; with extended span and the lengthened fuselage slung above the lower wing. Power plant was 120 h.p. Mercedes D II.