https://en.wikipedia.org/wiki/Fokker_D.VII
The Fokker D.VII was a German World War I fighter aircraft designed by Reinhold
Platz of the Fokker-Flugzeugwerke. Germany produced around 3,300 D.VII aircraft
quickly proved itself to be a formidable aircraft. The Armistice ending the war
specifically required Germany to surrender all D.VIIs to the Allies. Surviving
aircraft saw continued widespread service with many other countries in the years
after World War I.
Fokker's chief designer, Reinhold Platz, had been working on a series of
experimental planes, the V-series, since 1916. These aircraft were characterized
by the use of cantilever wings. Junkers had originated the idea in 1915 with the
first all-metal aircraft, the Junkers J 1, nicknamed Blechesel ("Sheet Metal
Donkey" or "Tin Donkey"). The resulting wings were thick, with a rounded leading
edge. This gave greater lift and more docile stalling behavior than the thin
wings commonly used at the time.
Late in 1917, Fokker built the experimental V 11 biplane, fitted with the
standard Mercedes D.IIIa engine. In January 1918, Idflieg held a fighter
competition at Adlershof. For the first time, frontline pilots would directly
participate in the evaluation and selection of new fighters. Fokker submitted
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, Reinhold Platz lengthened the rear fuselage by one
structural bay, and added a triangular vertical fin in front of the rudder. Upon
flying the modified V 11, Richthofen praised it as the best aircraft of the
competition. It offered excellent performance from the outdated Mercedes engine,
yet 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 production aircraft, which were designated
D.VII by Idflieg.
Many sources erroneously state that the D.VII was equipped with the 120 kW (160
hp) Mercedes D.III engine. The Germans themselves used the generic D.III
designation to describe later versions of that engine. The earliest production
D.VIIs were equipped with 170-180 hp Mercedes D.IIIa. Production quickly
switched to the intended standard engine, the higher-compression 134 kW (180-200
By mid-1918, some D.VIIs received the "overcompressed" 138 kW (185 hp) BMW IIIa,
the first product of the BMW firm. The BMW IIIa followed the SOHC, straight-six
configuration of the Mercedes D.III, but incorporated several improvements.
Increased displacement, higher compression, and an altitude-adjusting carburetor
produced a marked increase in speed and climb rate at high altitude. Because the
BMW IIIa was overcompressed, using full throttle at altitudes below 2,000 m
(6,700 ft) risked premature detonation in the cylinders and damage to the
engine. At low altitudes, full throttle could produce up to 179 kW (240 hp) for
a short time. Fokker-built aircraft with the new BMW engine were designated
D.VII(F), the suffix "F" standing for Max Friz, the engine's designer.
Role
Fighter
Manufacturer
Fokker-Flugzeugwerke
Designer
Reinhold Platz
First flight
January 1918
Primary user
Number built
approximately 3,300
The D.VII entered squadron service with Jasta 10 in early May 1918. When the
Fokker D.VII appeared on the Western Front in April 1918, Allied pilots at first
underestimated the new fighter because of its squarish, ungainly appearance, but
quickly revised their view. The type quickly proved to have many important
advantages over the 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 high maneuverability and ability to climb at high angles of
attack, its remarkably docile stall, and its reluctance to spin. It could
literally "hang on its prop" without stalling for brief periods of time,
spraying enemy aircraft from below with machine gun fire. These handling
characteristics contrasted with contemporary scouts such as the Camel and SPAD,
which stalled sharply and spun vigorously.
The D.VII also had problems. Several aircraft suffered rib failures and fabric
shedding on the upper wing. Heat from the engine sometimes ignited phosphorus
ammunition until cooling vents were installed in the engine cowling, and fuel
tanks sometimes broke at the seams. Aircraft built by the Fokker factory at
Schwerin were 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.
Specifications (D.VII with Mercedes D.III engine)
General characteristics
Crew: 1
Length: 6.954 m (22 ft 10 in)
Wingspan: 8.9 m (29 ft 2 in)
Height: 2.75 m (9 ft 0 in)
Wing area: 20.5 m2 (221 sq ft)
Empty weight: 670 kg (1,477 lb)
Gross weight: 906 kg (1,997 lb)
(160 hp)
engine
(240hp rating at low level, emergency only, risk of engine damage.)
Performance
Maximum speed: 189 km/h (117 mph; 102 kn)
BMW IIIa engine - 200 km/h (124 mph)
Service ceiling: 6,000 m (19,685 ft) [9]
Rate of climb: 3.92 m/s (772 ft/min)
Time to altitude:
1,000 m (3,281 ft) in 4 minutes 15 seconds (1 minutes 40 seconds w/ BMW
IIIa)[10]
2,000 m (6,562 ft) in 8 minutes 18 seconds (4 minutes 5 seconds w/ BMW IIIa)[10]
3,000 m (9,843 ft) in 13 minutes 49 seconds (7 minutes 0 seconds w/ BMW
IIIa)[10]
4,000 m (13,123 ft) in 22 minutes 48 seconds (10 minutes 15 seconds w/ BMW
IIIa)[10]
5,000 m (16,404 ft) in 38 minutes 5 seconds (14 minutes 0 seconds w/ BMW
IIIa)[10]
6,000 m (19,685 ft) (18 minutes 45 seconds w/ BMW IIIa) [10]
Armament
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