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Fokker Dr.I

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The Fokker Dr.I ( Dr eidecker , " triplane " in German ), often known simply as the Fokker Triplane , 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 17 victories (plus two earlier ones in the Fokker F.I prototype in September 1917), and in which he was killed on 21 April 1918. The Fokker Dr. 1 was flown with great success by many German aces, most notably Josef Jacobs with 30 confirmed kills in the type.

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62-715: 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 Luftstreitkräfte . In April 1917, Anthony Fokker viewed a captured Sopwith Triplane while visiting Jasta 11 . Upon his return to the Schwerin factory, Fokker instructed Reinhold Platz to build

124-450: A Sturzkommission (crash commission) which concluded that poor construction and lack of waterproofing had allowed moisture to damage the wing structure. This caused the wing ribs to disintegrate and the ailerons to break away in flight. In response to the crash investigation, Fokker was forced to improve quality control on the production line, particularly varnishing of the wing spars and ribs, to combat moisture. Fokker also strengthened

186-844: A consequence of the slow replacement of their Triplanes. By the end of 1917, surviving Triplanes were used as advanced trainers with No. 12 Naval Squadron . For a time, the type remained in use for experimental and training purposes; examples were recorded as performing flights as late as October 1918. Six British aces scored all of their victories on Sopwith Triplanes. These were John Albert Page (7), Thomas Culling (6), Cyril Askew Eyre (6), F. H. Maynard (6), Gerald Ewart Nash (6) and Anthony Arnold (5). Data from British Aeroplanes 1914–18 Aircraft Profile No. 73: The Sopwith Triplane General characteristics Performance Armament Related development Aircraft of comparable role, configuration, and era Motorenfabrik Oberursel Motorenfabrik Oberursel A.G.

248-554: A high level of manoeuvrability. The introduction of a smaller 8 ft span tailplane in February 1917 was attributed with improved elevator response. The original tail assembly was identical to the Pup's, other than the inclusion of the variable incidence tailplane , which could be adjusted so that the aircraft could be flown hands-off. The Triplane was initially powered by the 110 hp Clerget 9Z nine-cylinder rotary engine . However,

310-677: A production order for 100 triplanes in September, followed by an order for 200 in November. Apart from the straight leading edge of the tailplane, these aircraft were almost identical to the F.I. The primary distinguishing feature was the addition of wingtip skids, which proved necessary because the aircraft was tricky to land and prone to ground looping . In October, Fokker began delivering the Dr.I to squadrons within Richthofen's Jagdgeschwader I. Compared with

372-500: A single Triplane during the latter half of 1917, its fate being unknown. The Triplane's combat debut was highly successful. The new fighter's exceptional rate of climb and high service ceiling gave it a marked advantage over the Albatros D.III , though the Triplane was slower in a dive. During April 1917, Manfred von Richthofen , better known as The Red Baron , commented that the Triplane

434-454: A small one-cylinder stationary engine of about 4 hp, which he called the Gnom . The following year he founded Willy Seck & Co. to sell the design, which became famous around the world. The engine was improved to achieve more power, but in 1897 the shareholders refused to allow Seck to develop a Gnom-powered car and he left the company. The company was reorganized as Motorenfabrik Oberursel

496-444: A triplane, but gave him no further information about the Sopwith design. Platz responded with 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 . Instead of submitting

558-548: Is a British single seat fighter aircraft designed and manufactured by the Sopwith Aviation Company during the First World War . It has the distinction of being the first military triplane to see operational service. The Triplane was developed by the firm's experimental department as a private venture, the project was headed by the designer Herbert Smith . Aside from its obvious difference in wing configuration,

620-684: Is largely unknown, only that its use was curtailed after a crash-landing in Salonika on 26 March 1917. Aside from the British, the only other major operator of the Triplane was a French naval squadron based at Dunkirk, which received 17 aircraft. A single example was shipped to the United States for exhibition purposes in December 1917. Furthermore, the Imperial Russian Air Service also operated

682-521: Is the oldest surviving example of the Dr.1. Because of the expense and scarcity of authentic rotary engines , most airworthy replicas are powered by a Warner Scarab or Continental R-670 radial engine. A few, however, feature vintage Le Rhône 9J or reproduction Oberursel Ur.II rotary engines. Data from Quest for Performance. General characteristics Performance Armament Aircraft of comparable role, configuration, and era Sopwith Triplane The Sopwith Triplane

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744-521: The Admiralty . During early 1917, production examples of the Triplane arrived with Royal Naval Air Service squadrons. The Triplane rapidly proved to be capable of outstanding agility, and thus was quickly deemed to be a success amongst those squadrons that flew it. Praise for the type extended to opposing pilots; Imperial Germany extensively studied the Triplane via captured examples and produced numerous tri-winged aircraft shortly thereafter. Nevertheless,

806-507: The DZ 720 32-cylinder H-block made from twinned 710's. The firm was also responsible for manufacturing the largest number (at some 12,500 units) of the German Wehrmacht military's Raupenschlepper Ost fully tracked artillery tractor design. None of the firm's engine designs reached operational use by the end of the war, when the factory was occupied by US troops. For a short period in 1946

868-701: The Fokker V.4 , prototype of the successful Fokker Dr.I . Pilots nicknamed the aircraft the Tripehound or simply the Tripe . The Triplane was famously flown by "B" Flight 10 Naval Squadron, better known as the "Black Flight". This all- Canadian flight was commanded by the ace Raymond Collishaw . Their aircraft, named Black Maria , Black Prince , Black George , Black Death and Black Sheep , were distinguishable by their black-painted fins and cowlings. The Black Flight claimed 87 German aircraft in three months while equipped with

930-538: The Klöckner-Humboldt-Deutz Oberursel factory, known primarily for their locomotive engines. Today they are part of Rolls-Royce Deutschland , and produce one family of their jet engines . The factory in Oberursel is claimed to be the oldest surviving aircraft engine factory in the world. The company had its origins in 1891, when Willy Seck invented a new gasoline fuel injection system and produced

992-580: The Royal Flying Corps (RFC), the War Office also issued a contract to Clayton & Shuttleworth for 106 Triplanes. Quantity production of the type commenced in late 1916. The first Sopwith-built Triplanes were delivered to Clayton & Shuttleworth, who delivered their first Triplane on 2 December 1916. A renewed urgency amongst the Allied Powers for high performance combat aircraft came following

1054-511: The Sopwith Aviation Company became a prominent British manufacturer of military aircraft. It was amid this conflict that one of its employees, Herbert Smith , designed the Sopwith Pup , a single-seat biplane fighter aircraft which was described by aviation author J.M. Bruce as being "one of the world's greatest aeroplanes". While it was a capable fighter that possessed impressive handling qualities for its era, from an aerodynamic perspective,

1116-570: 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 General der Luftstreitkräfte ) that the F.I was superior to the Sopwith Triplane. Richthofen recommended that fighter squadrons be reequipped with

1178-636: 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 because it had such wonderful flying qualities. I could let myself stunt – looping and rolling – and could avoid an enemy by diving with perfect safety. The triplane had to be given up because although it

1240-622: The Armistice. Serial 528/17 was retained as a testbed by the Deutschen Versuchsanstalt für Luftfahrt (German Aviation Research Institute) at Adlershof. After being used in the filming of two movies, 528/17 is believed to have crashed sometime in the late 1930s. Serial 152/17, in which Manfred von Richthofen obtained three victories, was displayed at the Zeughaus museum in Berlin. This aircraft

1302-519: The Oberursel firm as the Oberursel U.0 Umlaufmotor (the generic German term for a rotary engine) as their first-ever powerplant for German military aircraft, and was used on the initial versions of the famous Fokker Eindecker fighter, the Fokker E.I . When World War I started the following year the Oberursel U.I of 100 hp, a licensed copy of the Gnome Delta 100 hp (75 kW) rotary, had

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1364-402: The Pup was an entirely conventional design. Certain figures, including those within Sopwith's experimental department, sought to develop a successor which would instead pioneer new concepts for such an aircraft; out of such ambitions would emerge the Triplane. Early on, Sopwith decided to pursue development of the Triplane concept as a private venture initiative. The design, which was passed by

1426-417: The Pup. It has been described as being a "remarkably simple aircraft". The initial "prototype of what was to be referred to simply as the Triplane" first flew on 28 May 1916, with Sopwith test pilot Harry Hawker at the controls. Within three minutes of takeoff, Hawker startled onlookers by looping the aircraft, serial N500, three times in succession. Hawker noted that this was due to his high confidence in

1488-471: The Triplane was built in comparatively small numbers to that of the more conventional Sopwith Pup . It had been decided to withdraw the Triplane from active service as increasing numbers of the Sopwith Camel arrived in the latter half of 1917. Surviving Triplanes continued to serve as operational trainers and experimental aircraft until months following the end of the conflict. During the First World War ,

1550-425: The Triplane. Collishaw scored 34 of his eventual 60 victories in the aircraft, making him the top Triplane ace. The Triplane's combat career was comparatively brief, in part because it proved difficult to repair. The fuel and oil tanks were inaccessible without dismantling the wings and fuselage; even relatively minor repairs had to be made at rear echelon repair depots. Spare parts became difficult to obtain during

1612-507: The UR.II had been rendered obsolete by its relatively low power and poor performance at altitude. An 11-cylinder development, the UR.III, was not used operationally. Indeed, by 1918, rotary engines had largely fallen from favor with the Idflieg and with pilots. The lack of castor oil and the poor quality of the mineral oil substitute "Voltol" severely reduced engine life and reliability. Nevertheless, in

1674-441: The V.4 for a type test, Fokker produced a revised prototype designated V.5 . The most notable changes were the introduction of horn-balanced ailerons and elevators, as well as longer-span wings. The V.5 also featured interplane struts , which were not necessary from a structural standpoint, but which minimized wing flexing. On 14 July 1917, Idflieg issued an order for 20 pre-production aircraft. The V.5 prototype, serial 101/17,

1736-535: The Western Front. 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. On 18 March 1918, Lothar von Richthofen , Staffelführer of Jasta 11, suffered a failure of the upper wing leading edge during combat with Sopwith Camels of No. 73 Squadron and Bristol F.2Bs of No. 62 Squadron. Richthofen

1798-427: The aircraft despite its radical design. The Triplane was very agile, with effective, well-harmonised controls. When maneuvering, however, the Triplane presented an unusual appearance. One observer noted that the aircraft looked like "a drunken flight of steps" when rolling. While initially lacking any armament, N500 was subsequently furnished with a single Vickers machine gun , which was mounted centrally in front of

1860-468: The aircraft shared many similarities with the company's successful biplane fighter, the Sopwith Pup . The prototype Triplane performed its maiden flight on 28 May 1916 and was dispatched to the French theatre two months later, where it garnered high praise for its exceptional rate of climb and high manoeuvrability. During late 1916, quantity production of the type commenced in response to orders received from

1922-565: The best power-to-weight ratio of any German engine. It went on to power most of the early German fighters, such as the Fokker and Pfalz E-series monoplanes. Oberursel also built a licensed copy of Gnome's 14-cylinder Double Lambda two-row rotary. This 160 hp (120 kW) engine, designated U.III in Germany, was difficult to build and quickly wore out in service. It was used on the Fokker E.IV and D.III designs. The 110 hp Oberursel UR.II ,

Fokker Dr.I - Misplaced Pages Continue

1984-495: The cockpit. In July 1916, N500 was sent to Dunkirk for evaluation with "A" Naval Squadron, 1 Naval Wing. Being put into action within 15 minutes of its arrival to intercept enemy aircraft, N500 quickly proved to be highly successful. According to Bruce, it demonstrated exemplary maneuverability and a phenomenal rate of climb for the era. The second prototype, N504, performed its maiden flight in August 1916. Its primary difference from

2046-486: The company's experimental department on 28 May 1916, was contemporary to the Sopwith L.R.T.Tr. project, which never progressed beyond the prototype stage; Bruce speculated that Smith may have been inspired by the L.R.T.Tr.'s atypical wing configuration to adopt the iconic triplane configuration for the new project. Beyond the obvious difference in terms of wing configuration, the Triplane's design largely conformed with that of

2108-462: The earlier Pup . While the fuselage was structurally similar, Bruce notes that there were several areas of differences present. One example was the attachment points present for the center wings, which were carried upon the top and bottom longerons of the fuselage and in turn also attached to the center-section struts. One innovation that was present only on the Triplane was the use of single broad-chord interplane struts, which ran continuously between

2170-593: The emergence of the Albatros D.II , which entered service with Imperial Germany around this same time frame, which threatened Allied aerial supremacy. In February 1917, the War Office agreed to exchange its Triplane orders for the Admiralty's SPAD S.VII contracts. While both Sopwith and Clayton & Shuttleworth successfully fulfilled their RNAS production orders, Oakley, which had no prior experience building aircraft, delivered only three Triplanes before its contract

2232-446: The factories were used as a tanks and trucks repair depot by the US army. In 1956 the factories were returned to Klöckner-Humboldt-Deutz, and from then on have been used primarily for gas turbine development and production. For the next twenty years they produced a variety of designs, typically under license from other companies. In 1980 they were renamed KHD Luftfahrttechnik GmbH . In 1990

2294-496: The first prototype was the installation of a 130 hp Clerget 9B engine. N504 was eventually dispatched to France in December of that year. This aircraft served as a conversion trainer for several squadrons. Between July 1916 and January 1917, the Admiralty issued two contracts to Sopwith for a total of 95 Triplanes, two contracts to Clayton & Shuttleworth Ltd. for a total of 46 aircraft, and one contract to Oakley & Co. Ltd. for 25 aircraft. Seeking modern aircraft for

2356-650: The inboard cabane struts of surviving Triplanes. One aircraft, serial N5912, was fitted with additional mid-bay flying wires on the upper wing while used as a trainer. Another drawback of the Triplane was its light armament. Contemporary Albatros fighters were armed with two guns but most Triplanes carried one synchronised Vickers machine gun . Efforts to fit twin guns to the Triplane met with mixed results. Clayton & Shuttleworth built six experimental Triplanes with twin guns. Some of these aircraft saw combat service with Nos. 1 and 10 Naval Squadrons in July 1917 but performance

2418-551: The licensed copy of the Le Rhône 9J of the same power output, was the next major success. Fokker bought the company in 1916 in order to guarantee supplies of the UR.II. This acquisition proved advantageous because Fokker was partial to rotary powered designs, and because supplies of the Mercedes D.III engine were limited. The UR.II was used in the Fokker Dr.I and Fokker D.VI . By 1917,

2480-400: The lower and upper wings. The most distinctive feature of the Triplane is its three narrow- chord wings; these provided the pilot with an improved field of view. These wings had the same span as that of the Pup, while being only 21 square feet less in terms of area. Ailerons were fitted to all three wings. The relatively narrow chord and short span wings have been attributed with providing

2542-411: The majority of production examples were instead fitted with the more powerful 130 hp Clerget 9B rotary. At least one Triplane was tested with a 110 hp Le Rhône rotary engine, but this did not provide a significant improvement in performance, the only seeming benefit being a slight increase in its rate of climb. No. 1 Naval Squadron became fully operational with the Triplane by December 1916, but

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2604-406: The new aircraft as soon as possible. The combat evaluation came to an abrupt conclusion when Oberleutnant Kurt Wolff , Staffelführer of Jasta 11 , was shot down in 102/17 on 15 September, and Leutnant Werner Voss , Staffelführer of Jasta 10, was killed in 103/17 on 23 September. The remaining pre-production aircraft, designated Dr.I , were delivered to Jasta 11. Idflieg issued

2666-723: The next year, and by 1900 had built 2,000 engines. The same year the company granted a license to the Seguin brothers in Lyon to produce the Gnom in France. Sold under the French name Gnome , the engine became so successful that they renamed their company to the same name. In 1908 they developed a rotary version of the basic Gnome system as the Gnome Omega aircraft engine, and from there a series of larger versions of

2728-576: The rib structures and the attachment of the auxiliary spars to the ribs. Existing triplanes were repaired and modified at Fokker's expense. After testing a modified wing at Adlershof, Idflieg authorized the triplane's return to service on 28 November 1917. Production resumed in early December. By January 1918, Jastas 6 and 11 were fully equipped with the triplane. Only 14 squadrons used the Dr.I as their primary equipment. Most of these units were part of Jagdgeschwadern I, II, or III. Frontline inventory peaked in late April 1918, with 171 aircraft in service on

2790-611: The same basic design. The new Gnome engines were wildly successful, powering many of the early record breaking aircraft. In 1913 Motorenfabrik Oberursel took out a license on the French Gnome engine design and the similar Le Rhône 9C . They produced both, the Gnomes as the U -series, and the Le Rhônes as the UR -series. The Gnome Lambda seven-cylinder 80 hp rotary engine was also produced by

2852-493: The squadron did not see any significant action until February 1917, when it relocated from Furnes to Chipilly . No. 8 Naval Squadron received its Triplanes in February 1917. Nos. 9 and 10 Naval Squadrons equipped with the type between April and May 1917. All but one British Triplane were dispatched to squadrons based in France; this sole aircraft was instead sent to the Aegean , although its service details and purpose there

2914-406: The summer of 1917, resulting in the reduction of No. 1 Naval Squadron's complement from 18 to 15 aircraft. According to Bruce, it is plausible that squadrons were slow to refit their Triplanes with the improved tailplane due to a lack of available kits for doing so. The Triplane also gained a reputation for structural weakness because the wings of some aircraft collapsed in steep dives. This defect

2976-482: The summer of 1918, the UR.II was installed in the Fokker D.VIII . The light weight and aerodynamic cleanliness of the D.VIII allowed it to achieve excellent performance even with the outdated UR.II. After the war the company was purchased in 1921 by Gasmotorenfabrik Deutz , another gasoline engine manufacturer, who moved their two-stroke diesel manufacturing to the Oberursel factories. In 1930 they merged with Humboldt-Deutz, but with only one product line. The factory

3038-468: The summer of 1918. The Dr.I suffered other deficiencies. The pilot's view was poor during takeoff and landing. The cockpit was cramped and furnished with materials of inferior quality. Furthermore, the proximity of the gun butts to the cockpit, combined with inadequate crash padding, left the pilot vulnerable to serious head injury in the event of a crash landing. On 29 October 1917, Leutnant der Reserve Heinrich Gontermann , Staffelführer of Jasta 15,

3100-463: Was a German manufacturer of automobile, locomotive and aircraft engines situated in Oberursel (Taunus) , near Frankfurt (Main) , Germany. During World War I it supplied a major 100 hp-class rotary engine that was used in a number of early-war fighter aircraft designs. In 1921 the company merged with Deutz AG , and then again in 1930 with Humboldt-Deutz Motoren , and finally in 1938 with Klöcknerwerke AG . From this point on they were known as

3162-461: Was attributed to the use of light gauge bracing wires in the 46 aircraft built by subcontractor Clayton & Shuttleworth. Several pilots of No. 10 Naval Squadron used cables or additional wires to strengthen their Triplanes. Bruce alleges that there was no substance to the concerns of structural weakness. In 1918, the RAF issued a technical order for the installation of a spanwise compression strut between

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3224-513: Was cancelled during October 1917. For unknown reasons, the RFC Triplane contract issued to Clayton & Shuttleworth was simply cancelled rather than being transferred to the RNAS. Total production of the type amounted to 147 aircraft. The Sopwith Triplane was a single seat fighter aircraft; it shared a considerable amount of its design features, such as its fuselage and empennage , with those of

3286-707: Was destroyed in an Allied bombing raid during World War II . In 1932, Fokker assembled a Dr.I from existing components. It was displayed in the Deutsche Luftfahrt-Sammlung in Berlin. In 1943, the aircraft was destroyed in an Allied bombing raid. Today, only a few original Dr.I artifacts survive in museums. Large numbers of replica and reproduction aircraft have been built for both individuals and museums. Bitz Flugzeugbau GmbH built two Dr.I replicas, serial numbers 001 and 002, for use in Twentieth Century Fox ’s 1966 film The Blue Max . Replica 001 EI-APW

3348-541: Was eventually closed in 1932 during the Great Depression , reopening in 1934 for small-scale production. In 1940 during World War II all diesel research was relocated to Oberursel, where Dr. Ing. Adolf Schnürle led the development of much larger and more advanced engines for aircraft use. This led to the Klöckner-Humboldt-Deutz DZ 700 8-cylinder radial engine , the DZ 710 16-cylinder boxer engine , and

3410-566: Was fitted with the Siemens-Halske Sh.III bi-rotary engine. The V.7 exhibited exceptional rate of climb and ceiling, but it proved difficult to handle. Serial 108/17 was used to test the 118 kW (160 hp) Goebel Goe. III, while serial 469/17 was used to test the 108 kW (145 hp) Oberursel Ur. III. None of these engines were used on production aircraft. One triplane was used as a testbed for an experimental Schwade gear-driven supercharger. Three triplanes are known to have survived

3472-477: Was performing aerobatics when his triplane broke up. Gontermann was killed in the ensuing crash landing. Leutnant der Reserve Günther Pastor of Jasta 11 was killed two days later when his triplane broke up in level flight. 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

3534-609: Was reduced and the single gun remained standard. Triplanes built by Oakley would have featured twin guns, an engineering change which severely delayed production. In June 1917, No. 4 Naval Squadron received the first Sopwith Camels and the advantages of the sturdier, better-armed fighter quickly became evident. Nos. 8 and 9 Naval Squadrons re-equipped with Camels between early July and early August 1917. No. 10 Naval Squadron converted in late August, turning over its remaining Triplanes to No. 1 Naval Squadron. No. 1 operated Triplanes until December, allegedly suffering heavy casualties as

3596-602: 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 lift coefficient than the lower wing – at high speeds it could be 2.55 times as much. The triplane's chronic structural problems destroyed any prospect of large-scale orders. Production eventually ended in May 1918, by which time only 320 had been manufactured. The Dr.I

3658-469: Was tested to destruction at Adlershof on 11 August 1917. 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 and could be distinguished from subsequent aircraft by a slight convex curve Archived 2010-11-03 at the Wayback Machine of

3720-427: Was the best Allied fighter at that time, a sentiment that was echoed by other German senior officers such as Ernst von Hoeppner . Multiple Triplanes were captured and subject to considerable evaluation and study. The Germans were so impressed by the aircraft's performance that it spawned a brief triplane craze among German aircraft manufacturers. Their efforts resulted in no fewer than 34 different prototypes, including

3782-625: Was very maneuverable, it was no longer fast enough." As Hemer noted, the Dr.I was considerably slower than contemporary Allied fighters in level flight and in a dive. While initial rate of climb was excellent, performance fell off dramatically at higher altitudes because of the low compression of the Oberursel Ur.II, a clone of the Le Rhône 9J rotary engine. As the war continued, chronic shortages of castor oil made rotary operation increasingly difficult. The poor quality of German ersatz lubricant resulted in many engine failures, particularly during

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3844-781: Was withdrawn from frontline service as the Fokker D.VII entered widespread service in June and July. Jasta 19 was the last squadron to be fully equipped with the Dr.I. Surviving triplanes were distributed to training and home defense units. Several training aircraft were reengined with the 75 kW (100 hp) Goebel Goe.II. At the time of the Armistice , many remaining triplanes were assigned to fighter training schools at Nivelles , Belgium, and Valenciennes , France. Allied pilots tested several of these triplanes and found their handling qualities to be impressive. Several Dr.Is were used as testbeds for experimental engines. One aircraft, designated V.7,

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