В.Кондратьев Самолеты первой мировой войны
Вскоре после запуска в серию истребителя-триплана Dr.I фирма "Фоккер" вернулась к "традиционной" бипланной схеме. В декабре 1917 г. Рейнольд Платц, разработал самолет под заводским обозначением V.13. Его фюзеляж был практически идентичен фюзеляжу "драйдеккера", но, вместо трех несущих плоскостей, самолет имел два крыла увеличенного размера и площади, соединенных N-образными стойками из стальных труб. От своего предшественника машина унаследовала толстый профиль деревянных крыльев с полотняной обшивкой и безрасчалочную схему бипланной коробки.
В январе-феврале 1918 г. V.13 принимал участие в конкурсе перспективных моделей истребителей в Адлерсхофе. Самолет показал хорошие скоростные данные, но по другим параметрам - уступил более энерговооруженному и аэродинамичному истребителю той же фирмы "Фоккер" D.VII, который приняли на вооружение по результатам конкурса.
Тем не менее, с апреля по август 1918-го была построена небольшая серия в 59 машин, получивших обозначение "Фоккер" D.VI. Во многих из них них использовался задел двигателей, деталей и узлов, собранный для только что снятого с производства Dr. I. Большинство самолетов оснащалась немецкими ротативными двигателями "Оберурсель" Ur.II, остальные - шведскими моторами "Тулин". Вооружение - два синхропулемета LMG 08/15. Первый серийный экземпляр построен 26 апреля 1918 года.
Лишь незначительное число D.VI в течение лета поступило на вооружение немецких истребительных эскадрилий западного фронта, большинство же отправили в учебные подразделения.
Семь самолетов в августе 1918 г. приобрела Австро-Венгрия. Эти машины были куплены без вооружения и оснащены австрийскими авиапулеметами "Шварцлозе".
ДВИГАТЕЛЬ: "Рон" шведской постройки (110 л.с.) или аналогичный "Гебель Гоэ" германского производства.
ВООРУЖЕНИЕ: идентично "Фоккеру" Dr.I.
Размах, м 7,66
Длина, м 6,19
Площадь крыла, кв.м 17,7
Сухой вес, кг 392
Взлетный вес, кг 582
Скорость максимальная, км/ч 190
Время подъема на высоту
2000 м, мин.сек 5,30
Потолок, м 5940
O.Thetford, P.Gray German Aircraft of the First World War (Putnam)
Fokker V 9
Built in the autumn of 1917, the V 9 again used many of the triplane subassemblies. The lower wing featured the single compound spar as in the Dr 1; the upper wing had two spars. No less than two pyramids of three struts supported the centre-section on either side, making a round dozen struts altogether. Engine was at first 80 h.p. Oberursel U O, but later the 110 h.p. U II was fitted. Span, 7.7 m. (25 ft. 3 1/8 in.). Length, 5.9 m. (19 ft. 4 3/8 in.). Area, 17.1 sq.m. (184.68 sq.ft.). Loaded weight, 580 kg. (1,276 lb.).
Fokker V 13
Two versions of the V 13 were built, one powered with 145 h.p. Oberursel U III and the other (above) with 160 h.p. Siemens-Halske Sh III geared rotary. The type was developed from the earlier V 9, but had a lower wing with two spars and "N" interplane struts. The centre-section struts were also simplified. As may be seen, the Siemens-engined version required a very stalky undercarriage to give the necessary clearance for the large-diameter, slow-revolving (900 r.p.m.) airscrew. The Oberursel-engined model eventually went into small-scale production as the D VI with the lower-powered U II of 110 h.p. installed. At the D types Competition the V 13, at a loaded weight of 668 kg. (1,470 lb.), climbed to 4.900 m. (13,448 ft.) in 19.5 min. on 3rd February 1918 in the hands of test pilot Matthias.
Fokker D VI
During the winter of 1917-18 two rotary-engined prototypes designated V 13/1 and 13/2 were being built in the Fokker works at Schwerin. These aircraft were powered with the new 145 h.p. Oberursel U III and 160 h.p. Siemens-Halske Sh III engines respectively and made their first public appearance when sent to Adlershof for the first of the D type competitions in January 1918. Although both engines were far from trouble-free, the airframe itself was considered promising enough to place a small production order. Production aircraft were, however, to be fitted with the eminently reliable 110 h.p. Oberursel U II, which engine was virtually a straight copy of the French 110 h.p. Le Rhone.
From April 1918 production continued alongside the D VII, but was comparatively slow due to the priority accorded the latter, and when D VI production was terminated in August in order to accelerate D VII supplies, only fifty-nine examples had been built. Of these some seven aircraft were handed over to the Austro-Hungarians, and it has been reported that on these aircraft armament consisted of twin Madschlinger automatic rifles mounted on top of the upper wing, but it seems more likely that they were in fact fitted with Schwarzlose machine-guns. A few D Vis found their way variously to front-line units, one of which was Jasta 84; the remaining machines were used by the fighter-pilot training units.
An intelligence report extract recorded that about 5th August 1918 Jasta 80 received six D VIs, but they could not be used much due to poor quality oil and consequent unreliability of the Oberursel engine.
In design and construction the Fokker D VI was something of a hybrid, be fuselage and tail surfaces stemming from the Dr I and the wings being a scaled-down D VII derivation. The 110 h.p. Oberursel rotary engine was enclosed in a cowling which extended to the lower longerons and which was fitted with a faceplate fretted with two large circular vent holes. The fuselage structure was of welded steel tube which reduced in diameter as it tapered to a vertical knife-edge aft. All bays were braced by a loop of cable joined with a single turnbuckle for tensioning. Triangular sheets of ply, to form a faired profile, were clipped to either side of the nose and extended as far back as the cockpit. The rounded top decking forward of the cockpit was also ply-covered, and another triangular ply panel was clipped aft if the cockpit, and all was then completely covered with fabric. Of steel tube framing, the balanced rudder was of the distinctive comma profile and hinged directly to the sternpost. The triangular tailplane and split, balanced elevators continued the triangular outline and were likewise of steel tube and fabric covered. Two steel struts braced the tailplane to the underside of the fuselage.
In construction, the cantilever wings were greatly similar to those of the D VII. They were based on two hollow box-spars of deep section that tapered towards the tips (the taper being on the lower side only, the top was perfectly flat), on which were threaded the plywood ribs, which were extensively fretted with lightening holes. The leading edge was covered with thin three-ply sheet as far back as the front spar, to which the edge of the ply was tacked. Both wings were in one piece, the spars of the lower wing passing right through the fuselage, as in both the D VII and the earlier Dr I. Overhung, balanced ailerons were fitted to the t op wing only. They were framed from welded steel tube and operated by cables running through the top wing and attaching to control horns: all surfaces were fabric covered. The forward pyramid and single rear centre-section struts were exactly as in the D VII, and likewise of streamlined steel tube. The "N" type interplane struts were also of streamlined steel tube and served largely as ties simply to stop the wings vibrating rather than in any great structural capacity. No cables were used to brace the wings.
With its lifting surface axle fairing, the undercarriage chassis was almost identical to that of the Dr I, although the track was increased considerably to improve ground stability and lessen the tendency to pirouette. The vee struts were of streamlined steel tube, and elastic-cord shock absorbers bound the axle to the cast housing at the apex. An ash tailskid, internally sprung, was fitted just forward of the sternpost.
Although the pilot sat rather below the top wing in the D VI, the wide centre-section cut-out gave a good view from the cockpit. The machine was comparatively fast - faster at low altitude than the D VII - and of good manoeuvrability. If it had not been for the eventual success of the D VIII, it would doubtless have been built in greater numbers.
Description: Single-seat fighter.
Manufacturer: Fokker Flugzeug-Werke G.m.b.H. Schwerin am Mecklenburg (Fok.).
Power Plant: One 110 h.p. Oberursel U II 9 cylinder rotary engine.
Dimensions: Span, 765 m. (25 ft. 1 1/4 in.). Length, 6.23 m. (20 ft. 5 3/8 in.). Height, 2.55 m. (8 ft. 4 3/8 in.). Area, 17.7 sq.m. (191 sq.ft.).
Weights: Empty, 393 kg. (865 lb.). Loaded, 583 kg. (1,283 lb.).
Performance: Maximum speed, 196 km.hr (122.5 m.p.h.). Climb, 1,000 m. (3,280 ft.) in 2.5 min., 3,000 m. (9,840 ft.) in 9 min.. 5,000 m. (16.400 ft.) in 19 min. Duration, ca . 1 1/2 hr.
Armament: Two Spandau machine-guns firing forward.
Fokker V 31
V 31 was simply a modified Mercedes-engined two-seater Fokker D VI with towing gear to act as a tug for the V 30. No photograph available.
Fokker V 33
In the summer of 1918 Platz made a partial redesign of the V 9, with a twin-spar lower wing fitted and with unbalanced, high-aspect-ratio ailerons fitted to the upper wing. The rudder at last made a departure from the previous rounded-comma pattern which, either with or without fin, had characterised all Fokker aircraft. The V 33 was a handy little machine which Anthony Fokker himself used as a personal aircraft. He took it back to Holland with him after the war, where it was flown from Schipo as late as 1922. Engine was 110 h.p. Oberursel U II.
W.Green, G.Swanborough The Complete Book of Fighters
FOKKER D VI Germany
One of the single-seat fighter types evolved by Fokker for participation in the first D-type competition (the so-called D-Flugzeug-Wettbewerbe) that was to be held at Adlershof in January 1918 was the V 9 ordered on 24 August 1917 with a 110 hp Oberursel Ur II rotary. An unequal-span, single-bay, staggered biplane with fuselage, engine installation, undercarriage and tail assembly virtually identical with those of the Dr I, the V 9 was followed by five further prototypes, these being the similarly-powered V 12 and V 16, the 160 hp Steyr-built Le Rhone-engined V14, and two 160 hp Siemens-Halske Sh III-engined V 13s. The V 13s participated in the D-type competition, and, despite the fact that the Sh III engine was unavailable, this type was ordered into production by the Idflieg as the D VI. It was necessary to install the 100 hp Ur II engine in the series model, which, although manoeuvrable and offering a relatively good performance for the power available, was eclipsed in every respect by the parallel D VII. Orders were, in fact, placed for 270 D VIs, but these were cut back to 60 of which seven, plus the V12, were delivered to the Austro-Hungarian Luftfahrttruppe. The armament of the D VI consisted of paired synchronised 7,92-mm LMG 08/15 guns and the type was confined by the Fliegertruppen to home defence tasks.
Max speed, 122 mph (196 km/h).
Time to 3,280 ft (1000 m), 2.5 min.
Range 186 mis (300 km).
Empty weight, 866 lb (393 kg).
Loaded weight, 1,290 lb (585 kg).
Span, 25 ft 1 in (7,65 m).
Length, 20 ft 5 1/4in (6,23 m).
Height, 8 ft 4 1/3 in (2,55 m).
Wing area, 190.53 sq ft (17,70 m2).
FOKKER V 33 Germany
The V 33 was the ultimate development of the line of rotary-engined fighter biplanes stemming from the V 9. Smaller and lighter than preceding fighters in the series, the V 33 was apparently intended as a contender in the final D-type competition, although, in the event, it did not compete. It was initially flown with a 110 hp Oberursel Ur II nine-cylinder rotary, this eventually being replaced by a 145 hp Ur III 11-cylinder rotary. The single example of the V 33 was taken to the Netherlands after the Armistice and used by Anthony Fokker as his personal aircraft until 1922. The following data are applicable to the V 33 after application of the Ur III engine.
Time to 9,840 ft (3 000 m), 7.4 min.
Empty weight, 875 lb (397 kg).
Loaded weight, 1,358 lb (616 kg).
Span, 23 ft 9 in (7,24 m).
Length, 17 ft 10 4/5 in (5,46m).
Height, 7 ft 7 in (2,31m).
Wing area, 147.47 sq ft (13,70 m2).