The AEG D.I was a prototype biplane fighter built by the (AEG) during the First World War for the Imperial German Army's () Imperial German Air Service (). Three prototypes were ordered in 1917, but after the first two were involved in fatal crashes, development was cancelled. A triplane version was built as the Dr.I.
Development
AEG designed the prototype single-seat D.I fighter in early 1917. It used the company's typical steel tubing for the fuselage, but the single-bay wings also used a single spar built from steel tubing. The ribs were initially made from wood, but they were later changed to steel. The additional strength that the steel tubing added to the wings allowed AEG to minimize the number of drag-inducing wire braces and reduced the number of interplane struts to a single I-strut per side. The D.I was powered by a water-cooled Mercedes D.III straight-six piston engine that used a nose-mounted radiator. It was armed with a pair of forward-firing LMG 08/15 machine guns.
The first prototype was completed in May 1917. Flight testing revealed a maximum speed of and a climb rate that matched that of the Albatros D.V fighter then entering service. It was the fastest German fighter at that time and the Inspectorate of Flying Troops ( () ordered a batch of three aircraft for further testing. A pre-production batch of 20 aircraft was ordered in July contingent on passing the static load testing between 28 June and 3 July saw the wings pass, but the fuselage failed. A reinforced replacement was supplied by AEG and it passed on 4 August. Around this time the fuselage of the second prototype was lengthened to improve lateral stability and the aircraft's landing characteristics.
Variants
;AEG. D.I
:1917 prototype single-seat biplane fighter. A.E.G. Aircraft of WWI: A Centennial Perspective on Great War Airplanes
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Armament
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