https://en.wikipedia.org/wiki/Fokker_Dr.I
The Fokker Dr.I (Dreidecker, "triplane" in German) was a World War I fighter
aircraft built by Fokker-Flugzeugwerke. The Dr.I saw widespread service in the
spring of 1918. It became famous as the aircraft in which Manfred von Richthofen
gained his last 19 victories, and in which he was killed on 21 April 1918.
In February 1917, the Sopwith Triplane began to appear over the Western Front.
Despite its single Vickers machine gun armament, the Sopwith swiftly proved
itself superior to the more heavily armed Albatros fighters then in use by the
biplane prototype into the V.4, a small, rotary-powered triplane with a steel
tube fuselage and thick cantilever wings, first developed during Fokker's
government-mandated collaboration with Hugo Junkers. Initial tests revealed that
the V.4 had unacceptably high control forces resulting from the use of
unbalanced ailerons and elevators.
The first two pre-production triplanes were designated F.I, in accord with
Idflieg's early class prefix for triplanes. These aircraft, serials 102/17 and
103/17, were the only machines to receive the F.I designation[8] and could be
distinguished from subsequent aircraft by a slight convex curve of the
tailplane's leading edge. The two aircraft were sent to Jastas 10 and 11 for
combat evaluation, arriving at Markebeeke, Belgium on 28 August 1917.
Richthofen first flew 102/17 on 1 September 1917 and shot down two enemy
aircraft in the next two days. He reported to the Kogenluft (Kommandierender
Richthofen recommended that fighter squadrons be reequipped with the new
aircraft as soon as possible.[9] The combat evaluation came to an abrupt
10, was killed in 103/17 on 23 September.
Role Fighter
Manufacturer Fokker-Flugzeugwerke
Designer Reinhold Platz
First flight 5 July 1917
Number built 320
Compared to the Albatros and Pfalz fighters, the Dr.I offered exceptional
maneuverability. Though the ailerons were not very effective, the rudder and
elevator controls were light and powerful. Rapid turns, especially to the right,
were facilitated by the triplane's marked directional instability. Vizefeldwebel
Franz Hemer of Jasta 6 said, "The triplane was my favorite fighting machine
The triplane had to be given up because although it was very maneuverable, it
was no longer fast enough.
Jasta 15, was performing aerobatics when his triplane broke up.[20] Gontermann
Pastor of Jasta 11 was killed two days later when his triplane broke up in level
flight.[20] Inspection of the wrecked aircraft showed that the wings had been
poorly constructed. Examination of other high-time triplanes confirmed these
findings. On 2 November, Idflieg grounded all remaining triplanes pending an
inquiry. Idflieg convened a Sturzkommission (crash commission) which concluded
that poor construction and lack of waterproofing had allowed moisture to damage
the wing structure.[21] This caused the wing ribs to disintegrate and the
ailerons to break away in flight.
Despite corrective measures, the Dr.I continued to suffer from wing failures. On
3 February 1918, Leutnant Hans Joachim Wolff of Jasta 11 successfully landed
after suffering a failure of the upper wing leading edge and ribs.[26] On 18
of the upper wing leading edge during combat with Sopwith Camels of No. 73
Squadron and Bristol F.2Bs of No. 62 Squadron.[27] Richthofen was seriously
injured in the ensuing crash landing.
Postwar research revealed that poor workmanship was not the only cause of the
triplane's structural failures. In 1929, National Advisory Committee for
Aeronautics (NACA) investigations found that the upper wing carried a higher
much.
Specifications (Dr.I)
General characteristics
Crew: One
Length: 5.77 m (18 ft 11 in)
Wingspan: 7.19 m (23 ft 7 in)
Height: 2.95 m (9 ft 8 in)
Wing area: 18.70 m2 (201 ft2)
Empty weight: 406 kg (895 lb)
Loaded weight: 586 kg (1,291 lb)
Zero-lift drag coefficient: 0.0323
Drag area: 0.62 m2 (6.69 ft2)
Aspect ratio: 4.04
Performance
Maximum speed: 185 km/h at sea level (115 mph at sea level)
Stall speed: 72 km/h (45 mph)
Range: 300 km (185 mi)
Service ceiling: 6,100 m (20,000 ft)
Rate of climb: 5.7 m/s (1,130 ft/min)
Lift-to-drag ratio: 8.0
Armament
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