AEG J.I

{{Short description|German ground-attack biplane from WW1}}  {{Infobox aircraft |name = AEG J.I |image = File:AEG J.I - Ray Wagner Collection Image (21417553246).jpg |caption =  |type = Armoured ground attack aircraft |national_origin = [[Germany]] |manufacturer = [[Allgemeine Elektricitäts-Gesellschaft|AEG]] |designer =  |first_flight =  |introduction =  |retired =  |status =  |primary_user = ''[[Luftstreitkräfte]]'' |more_users =  |produced = 1917–1918<ref name="Grey and Thetford pp. 9-10">Grey and Thetford 1962, pp. 9-10.</ref> |number_built = 609<ref name="Grey and Thetford p. 11"/> |program cost =  |unit cost =  |developed_from = [[AEG C.IV]] |variants =  }}

The '''AEG J.I''' was a German [[biplane]] [[ground attack aircraft]] designed and produced by the German aircraft manufacturer [[AEG (German company)|Allgemeine Elektricitäts-Gesellschaft]]. It was a mission-specific derivative of the [[AEG C.IV]] [[reconnaissance aircraft]].

The J.I was developed as an interim ground attack aircraft, being redesigned from the C.IV to feature armour plating and the more powerful [[Benz Bz IV]] piston engine. For engaging ground targets, a pair of 7.92 mm downward-facing (.312 in) [[MG 08|LMG 08/15]] [[machine gun]]s were equipped. The aircraft's design was kept as similar to the C.IV as possible to minimise development and production schedules; however, to offset that aircraft's increased weight, it was necessary to add lower wingtip [[aileron]]s as well as to reinforce the [[shock absorbers]]. A key visual difference between the C.IV and J.I was the latter's angular nose due to the armouring.

An improved model, the ''J.II'', was produced in 1918 during the closing months of the war; it featured aerodynamic improvements and an extended fuselage. Around 609 aircraft, both J.Is and J.IIs, had been produced by the enactment of the [[Armistice of 11 November 1918]] that ended the conflict. The type saw limited use following the war. Multiple J.IIs served the first sustained daily passenger aeroplane service in the world, between the German cities of [[Berlin]] and [[Weimar]], launched by [[Deutsche Luft-Reederei]] on 5 February 1919.

==Design and development== During 1917, Germany undertook the formation and equipping of several [[Infanterie-Flieger]] units; military planners was decided that an interim aircraft would be needed for these units prior to the arrival of adequate numbers of purpose-built aircraft such as the [[Junkers J.I]].<ref name="Grey and Thetford p. 9"/> The AEG J.I, being a relatively straightforward development of the [[AEG C.IV]] [[reconnaissance aircraft]], could be hastily put into production and thus was deemed suitable for fulfilling this role. The principal changes between the C.IV and the J.I were the adoption of the more powerful [[Benz Bz IV]] in-line piston engine along with an armoured fuselage, the former helping to offset the additional 860 lb of weight of the latter.<ref name="Grey and Thetford p. 9">Grey and Thetford 1962, p. 9.</ref>

In terms of its basic configuration, the J.I was a twin-seat single-engined tractor biplane. Equipped with a conventional landing gear with a tail skid, it had steel tube structure and was mainly covered with [[fabric]]. The armour plating, which extended from the aircraft's nose to just aft of the rear cockpit, was roughly 5.1 mm thick; this armouring was not intended to function as structural elements, being instead fixed to various structural members.<ref name="Grey and Thetford p. 9"/> The J.I's distinctive angular nose is a result of the armouring, which made little concession to shaping or aerodynamic refinement.<ref name="Grey and Thetford p. 9"/>

Both the pilot and gunner were seated in an open tandem cockpit that was protected with armour. The gunner was provisioned with three weapons, including a pair of 7.92 mm (.312 in) [[MG 08|LMG 08/15]] [[machine gun]]s fitted to the floor of the cockpit for use against ground targets, and a single 7.92 mm (.312 in) [[Parabellum MG14]] machine gun on a rotatable mounting to provide flexible defensive fire. Ammunition was belt-fed from a relatively large supply drum, while aiming was achieved via a rudimentary sight in the form of a circular hole in the forward-righthand side of the cockpit.<ref name="Grey and Thetford p. 9"/> Typically there was no forward-firing armament as the aircraft was intended to focus on strafing troops on the ground rather than engage in aerial combat; however, various non-standard armaments would often be fitted in the field.<ref name="Grey and Thetford pp. 9, 12">Grey and Thetford 1962, p. 9, 12.</ref>

While the prototype J.I had been equipped with an identical wing to that of the C.IV, it was determined that the greater weight of the aircraft necessitated greater lateral control; this was resolved with minimal redesign work to the overall wing via the addition of [[aileron]]s at the outer parts of the lower wing.<ref name="Grey and Thetford p. 10"/> Other modifications included the reinforcement of the [[shock absorbers]] to appropriately cope with the additional weight. Otherwise, conscious efforts were made to avoid unnecessary design changes from the C.IV.<ref name="Grey and Thetford p. 10">Grey and Thetford 1962, p. 10.</ref>

During 1918, a refined version of the J.I, designated ''J.II'', was developed.<ref name="Grey and Thetford p. 10"/> While this aircraft differed little in terms of structure from the J.I, it featured considerable changes in terms of its aerodynamics. All of the flight control surfaces, other than the lower ailerons, were redesigned; the incorporation of overhanging horn balances made the two models visually distinct from one another.<ref name="Grey and Thetford pp. 10-11">Grey and Thetford 1962, pp. 10-11.</ref> Another visible change was the extension of the rear fuselage; other changes included the fitting of an enlarged [[fin]] to improve directional stability and a repositioned aileron link strut.<ref name="Grey and Thetford p. 11">Grey and Thetford 1962, p. 11.</ref>

By the signing of the [[Armistice of 11 November 1918]], roughly 609 aircraft, both J.Is and J.IIs, had been produced.<ref name="Grey and Thetford p. 9"/>

The type saw use for several years following the end of the conflict. Multiple J.IIs served the first sustained daily passenger aeroplane service in the world, between the German cities of [[Berlin]] and [[Weimar]], flown by [[Deutsche Luft-Reederei]]. This route began on 5 February 1919. Early commercial J.IIs retained open cockpits, but modified versions with enclosed cabins for the two passengers were quickly produced and replaced them.<ref name="JEoA">{{cite book |title = Jane's Encyclopedia of Aviation |editor-first = Michael J.H. |editor-last = Taylor |publisher = Portland House |location = New York, US |year = 1989 |edition = Second |isbn = 0-517-69186-8}}</ref>

==Variants== [[File:AEG J.I rear.jpg|thumb|AEG J.I rear]] [[File:AEG J.II Kabine.jpg|thumb|AEG J.II cabin version with the German airline [[Deutsche Luft-Reederei]] in 1919]] ;AEG J.I :An armoured version of the [[AEG C.IV]] fitted with downward pointing machine guns in the floor of the rear cockpit for ground strafing and a defensive hand-aimed machine-gun in the observers cockpit.<ref name="Grey and Thetford p. 9"/> ;AEG J.Ia :The '''J.Ia''' version featured aileron controls on the lower wings, in addition to the upper.<ref name="Gray">{{cite book|last=Gray|first=Peter|author2=Owen Thetford|title=German Aircraft of the First World War|publisher=Putnam|location=London|year=1970|edition=2nd|isbn=0-370-00103-6}}</ref> ;AEG J.II :Structurally similar to the J.I, outfitted with ailerons aerodynamically balanced by large horn extensions at the wing-tips, increased fin area to improve directional stability and a re-located aileron link strut.<ref name="Grey and Thetford pp. 10-11"/>

==Operators== ;{{flag|German Empire}} *''[[Luftstreitkräfte]]'' * [[Deutsche Luft-Reederei]]

==Specifications (AEG J.I)== {{Aircraft specs |ref= ''German Aircraft of the First World War''<ref name="Grey and Thetford pp. 1112">Grey and Thetford 1962, pp. 11-12.</ref> |prime units?= met

|genhide=

|power/mass= |thrust/weight=

|more performance=  |guns= * up to 6 × 7.92 mm (.312 in) fixed, downwards-firing [[MG 08|LMG 08/15]] machine guns (standard fit of 2) * 1 × 7.92 mm (.312 in) [[Parabellum MG14]] in rear cockpit |bombs=

|avionics= }}

==See also== {{aircontent| |related= * [[AEG C.IV]] |similar aircraft= * [[Albatros J.I]] * [[Albatros J.II]] * [[Junkers J.I]] |lists= * [[List of military aircraft of Germany]] |see also= }}

==References== {{commons category}} {{Reflist}}

==Bibliography== * {{cite book |last1 = Gray |first1 = Peter |first2 = Owen |last2 = Thetford |title = German Aircraft of the First World War |publisher = Putnam |location = London, UK |year = 1970 |edition = 2nd |isbn = 0-370-00103-6}} * {{cite book |last1 = Herris |first1 = Jack |title = German Armored Warplanes of WWI: A Centennial Perspective of Great War Airplanes |date = 2012 |publisher = Aeronaut Books |location = Charleston, South Carolina, US |isbn = 978-1-935881-11-7 |series = Great War Aviation Centennial Series |volume = 4}} * [https://www.awm.gov.au/collection/C374347 Probably Villeselve, France. 19 April 1918. The tangled wreckage of a crashed AEG J I aircraft of a German squadron, probably Bayrische Flieger Abteilung 287 (Bavarian Flying Section 287), in a field. Leutnant Major Vizefeldwebel Benz was killed in this crash.]

[[Category:AEG aircraft|J.I]] [[Category:Single-engined tractor aircraft]] [[Category:Biplanes]] [[Category:1910s German attack aircraft]] [[Category:Aircraft first flown in 1917]]