World War I: Fokker Dr.I
Fokker Dr.I - General:
- Length: 18 ft. 11 in.
- Wingspan: 23 ft. 7 in.
- Height: 9 ft. 8 in.
- Wing Area: 201 sq. ft.
- Empty Weight: 895 lbs.
- Loaded Weight: 1,292 lbs.
- Crew: 1
Fokker Dr.I - Performance:
- Power Plant: 1 × Oberursel Ur.II 9-cylinder rotary engine, 110 hp
- Range: 185 miles
- Max Speed: 115 mph
- Ceiling: 20,000 ft.
Fokker Dr.I - Armament:
- 2 x 7.92 mm Spandau LMG 08/15 machine guns
Fokker Dr.I - Design & Development:
In April 1917, the Royal Naval Air Service introduced the Sopwith Triplane. Featuring three wings, the aircraft was an immediate success and proved itself superior to the current generation of German Albatros and Halberstadt fighters. Concerned by this new foe, the Imperial German Army Air Service turned to the aircraft industry for a triplane to comabat the Sopwith. Most German manufacturers, such as Albatros, Pfalz, and Fokker, responded with designs. At the first review, all but Fokker's were found deficient. Designed by Reinhold Platz, the Fokker triplane began life as the V.3.
A cantilever triplane with unbalanced ailerons and elevators, the V.3 possessed a tubular-steel frame fuselage and was powered by a small rotary engine. During in-house testing, Fokker found that the V.3 had some control issues as well as a disturbing about of wing vibration in flight. Modifying the design, Platz developed the V.4 which corrected many of the issues experienced with the V.3. This was accomplished through the lengthening of the wings and the introduction of interplane struts to reduce vibration.
Platz also added horn-balanced ailerons and elevators to improve control.
Impressed by the V.4, the Imperial German Army Air Service selected it for production. For final testing, two pre-production aircraft, designated F.I, were sent to front. There it was first flown by the famed Red Baron, Manfred von Richthofen, on September 1, 1917. Pleased with the new fighter's agility, Richthofen scored two killed in two days. The service life of these two aircraft proved short as one was lost on September 15 and the other on September 23 with ace Werner Voss at the controls. Re-designated the Fokker Dr.I, the aircraft began arriving at the front in early October.
Fokker Dr.I - Operational History:
These initial deliveries were all made to squadrons within Richthofen's Jagdgeschwader 1. Though slower than many contemporary fighters, the Dr.I compensated with its extreme maneuverability and superior rate of climb. After achieving early success, the aircraft was grounded at the end of October 1917, after Lieutenants Heinrich Gontermann (a 39-victory ace) and Günther Pastor were killed when their Dr.Is broke up in flight. Following the accidents, an investigation concluded that the crashes were result of poor craftsmanship and a lack of waterproofing on the wing ribs.
Fokker immediately moved to address these issues and improved their quality control procedures. Efforts were also made to strengthen the wing rib structures and ensure that all parts were varnished properly. In later November, the Dr.I took to the skies again with production resuming the following month. Despite Fokker's efforts, the aircraft continued to be plagued with structural failures. One of these nearly claimed the life of the Red Baron's brother, Lothar von Richthofen, on March 18, 1918, when the upper wing of his Dr.I collapsed.
Due to these issues, production of the Dr.I never matched that of other German fighters. During its production run from October 1917 to May 1918, only 320 Dr.Is were built. Remaining in service until the end of the war, the Dr.I was retired after the armistice. In 1929, the US National Advisory Committee for Aeronautics tested the Dr.I and found that the wing failures were due to the upper wing carrying a higher lift coefficient than the lower wings. Though the Dr.I is most commonly associated with Manfred von Richthofen, he only scored 20 of his 80 kills in the aircraft.
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