Albatros D.I–D.Va Legendary fighter


The plane was fitted with two-spar, rectangular wings with rounded wooden wingtips. The Albatros prototype was designed with canvas-covered wings of uneven depth: the upper had 1.75 m while the lower 1.60 m. Moreover, the latter had a slightly shorter wingspan than the former. In order to increase visibility a semi-circular cut-out was made in the upper wing mid-section. The lower wing was attached to the fuselage while the upper was based on an inverted V-shaped, steel tube pyramid. The wing cell was composed of two parallel struts with teardrop cross-section, braced with steel wire strings.

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The two-strut undercarriage had a fixed axle embedded in a cowling and was fitted with a rubber string shock absorber. The wooden tail skid had a rubber string absorber attached to the triangular stabilizing fin. Control surfaces were made of welded steel tubes, covered with canvas skin. The rudder had an aerodynamic corner balance. The Albatros was armed with two synchronized 7.92 mm 08/15 caliber LMG Spandau machine guns incorporating a synchronizing device developed by werkmeister Hedtke, later improved by werkmeister Semmler. It proved efficient, particularly when two machine guns were synchronized. In October 1916 the Idflieg required that the Fokker synchronizer be tested on the Albatros but it was prone to malfunction and cut the rate of fire in half. Consequently, Albatros Werke decided against it.
In May 1916 Oblt Rudolf Berthold examined the Albatros D.I serial D.423/16. According to the first edition of his biography, he is believed to have said: “I am keen on taking the Albatros into combat, we should have a larger force of these excellent aircraft.” He said that to von Thüne from Ideflieg, who allegedly replied: “I decide which plane goes into battle, not Oblt Berthold.”
Between June 9 and July 7 static trials were successfully conducted. The wing depth was redesigned to be equal, which would also make production easier; aerodynamic corner balance was added to the elevator.

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On July 11 Ideflieg recommended Albatos D.I to go into serial production and placed an order for 50 examples (serials D.421-470/16). The evaluation report also included some of the demonstrated performance specs: “it climbs to 5000 m in 38 minutes and achieves 170 km/h in level flight.” The first Albatros D.Is were manufactured with the 111 kW (150 hp) Benz Bz III, but with the arrival of the Mercedes engine subsequent machines were fitted with the new powerplant. It made the Albatros heavier but increased the fighter’s speed in level flight and in climbs.
The Albatros D.I had excellent aerodynamic qualities for a fighter. Vzfw Carl Holler of Jasta 6 described the new type: “It has an excellent climb-rate, reaching 5000 m is child’s play. It has an excellent dive speed which is important when attacking an enemy below. We no longer have to wait for kills, my two colleagues scored two in a short time.” Unfortunately the author of that statement was shot down by a Nieuport, because he “had not seen” it. Very limited field of view from the cockpit, c. 30° up and to the sides, turned out to be a serious shortcoming of the Albatros D.I.
The second drawback became apparent in service as the poor visibility of the target hindered accurate aiming, especially at high speeds.
Thirdly, the Windhoff radiator contributed not only to increased drag (thus reducing the plane’s performance) but if punctured or in case of a leak (which occurred quite often) the engine absorbed the cooling liquid and ceased, while the hot liquid scalded pilot’s face. On November 10, 1916 the use of Windhoff radiators was banned in frontline units.

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A design team swiftly addressed all the raised issues. The new, Albatros D.II (L.17) version was produced with the upper wing lowered by 30 cm and the support strut pyramid that had obscured forward visibility was replaced with a new N-shaped, outer support. The first Albatros D.IIs were produced with lateral radiators, but in subsequent examples they were replaced with a new Teves und Braun radiator fitted in the central upper wing. Minor redesign of the fuselage did not delay delivery of further 100 D.IIs (serials D.472- D.521/16 and D.890 – 939/16) ordered in August 1916. Both Albatros variants, the D.I and D.II, were manufactured in parallel. The next order for 100 planes (serials D.1700 – D.1799/16) was placed in September 1916, but since the Albatros works were not able to fulfill the contract on their own, for the first and only time, license-production was assigned in August 1916 to Luft Verkehrs Gesellschaft mbH (LVG) located in nearby Johanisthal. The seventy five examples (serials D.1024/16 – D.1098/16) built at L.V.G. were designated as LVG D.I, only to be re-designated in February 1917 as Albatros (LVG) D.II. They were easily recognizable by their paint scheme, i.e. the characteristic arrangement of color areas on top wing surfaces and the empennage. A total of fifty Albatros D.Is and 275 D.IIs was built at all factories.
A team of designers headed by engineer Thalen focused from the outset on improving the Albatros design. The D.II was selected as the platform they would work on to meet the challenge posed by new aircraft being pressed into service by the French and British, most notably the Nieuport 17C1. One way to go was to further upgrade the fighter’s aerodynamic characteristics by making it even sleeker and by redesigning onboard hardware to further minimize drag. The second task was to reduce the weight of Albatros by implementing the latest technologies of wood treatment and, finally, by utilizing enemy’s technical solutions, i.e. sesquiplane airframe layout which in fact meant copying the Nieuport design. Not much could be done to re-engine the airframe: the only available powerplants were the Mercedes D.III and Mercedes D.IIIa (a D.III derivative with higher compression ratio and increased capacity) delivering 120-129 kW (170-175 hp) and there were no signs that new, improved and more powerful engines were to arrive soon.

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Three designers, Thelen, Schubert and Gnadig built a new version incorporating only minor modifications. Having slightly redesigned the fuselage they applied a new wing arrangement. The upper wing had a 1.50 m chord and a trapezoid shape. The lower wing was of similar shape but its chord was reduced to 1.1. m. Consequently, the team produced a sesquiplane arrangement that replicated the same mistake that had been made by Nieuport designers – the lower wing had only one spar, which reduced its rigidity. Both wings were connected via V-shaped struts. The plane was more maneuverable than its D.I and D.II predecessors and was only a bit inferior to the Nieuport. Powered by the Mercedes D.IIIa engine it had a  good speed in level flight and a decent climb-rate. The Albatros D.III 388/16 underwent tests in September 1916 in parallel with the Albatros D.I and D.II. They were successful enough to make Ideflieg immediately order 400 examples (the highest number ever ordered at one time).
Along with the order, a suggestion was filed to use strips as fuselage skin due to shortage of plywood. Five planes were ordered for testing. The outcome was negative as strip-skinned fuselage offered less strength and its weight did not reduce much in comparison to plywood-covered counterparts. Consequently, the idea was abandoned, though Roland works took it up and applied in its designs.

 

 

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