{{Infobox aircraft | name = Euler D.I | logo = | logo_size = | image = | alt = | caption = | long_caption = | other_names = | aircraft_type = Fighter | aim = | outcome = | related = | national_origin = | manufacturer = Euler-Werke | design_group = | designer = August Euler | builder = | issuer = | status = | owners = | primary_user = Luftstreitkräfte | more_users = | service = | major_applications = | proposals = | prototypes = | number_built = around 75 | construction_number = | civil_registration = | military_serial = | radio_code = | requirement = | aircraft_carried = | flights = | total_hours = | total_distance = | construction_date = | introduction = 1917 | retired = 1920 | first_flight = Autumn 1916 | initiated = | in_service = | last_flight = | expected = | developed_from = | variants = Euler D.II | developed_into = | preservation = | fate = | predecessors = | successors = | concluded = }}

The '''Euler D.I''' was a German single-seat fighter based on the French Nieuport 11.<ref name=":SY1">{{Cite book |last=Green |first=William |title=The Complete Book of Fighters |last2=Swanborough |first2=Gordon |date=1994 |publisher= |isbn=0861016432 |volume= |location=United Kingdom |pages=149 |language= |trans-title= |chapter=}}</ref><ref>{{Cite book |last=Gray |first=Peter |title=German Aircraft of the First World War |last2=Thetford |first2=Owen |date=1962 |publisher=Doubleday and Company |edition=2nd |location=United States |pages=329}}</ref> After seeing the success of the French Nieuport 11 at the front, German designer August Euler set about to create a German aircraft based on the Nieuport design. The Euler D.I first flew in late 1916. It was powered by an 80&nbsp;hp engine with the Euler patented machine gun on the front.<ref name=":SY1" />

==Operational history== Two prototypes were recorded as being in service at the front in October 1916, and the German government ordered 50 in the same month. A further 50 were ordered in early 1917, but this order was largely transferred over to the D.I's successor, the Euler D.II. The plane saw very little combat service, being largely used as a fighter trainer for the remainder of the war.<ref name=":SY1" />

==Operators== ;{{flag|German Empire}} *Luftstreitkräfte;

==Specifications== {{Aircraft specs |ref=<ref name=":SY1" /> |prime units?=met <!-- General characteristics --> |crew=1 |length m=8.1 |length note= |span m=13 |span note= |height m=2.66 |height note= |wing area sqm=13 |wing area note= |aspect ratio=<!-- sailplanes --> |airfoil= |empty weight kg=380 |empty weight note= |gross weight kg=600 |gross weight note= |max takeoff weight kg= |max takeoff weight note= |fuel capacity= |more general= <!-- Powerplant --> |eng1 number=1 |eng1 name=Oberursel U.0 |eng1 type=7-cylinder air-cooled radial piston engine |eng1 hp=80 |eng1 note=

|prop blade number=2 |prop name=wooden fixed-pitch propeller |prop dia m=<!-- propeller aircraft --> |prop dia note= <!-- Performance --> |max speed kmh=140 |max speed note= |cruise speed kmh= |cruise speed note= |stall speed kmh= |stall speed note= |never exceed speed kmh= |never exceed speed note= |range km= |range note= |combat range km= |combat range note= |ferry range km= |ferry range note= |endurance=<!-- if range unknown --> |ceiling m= |ceiling note= |g limits=<!-- aerobatic --> |roll rate=<!-- aerobatic --> |climb rate ms= |climb rate note= |time to altitude={{cvt|2000|m}} in 12.5 minutes |wing loading kg/m2= |wing loading note= |fuel consumption kg/km= |power/mass= |more performance= <!-- Armament --> |guns=1 x engine-mounted 7.92-mm machine gun}}

== References == <!-- Inline citations added to your article will automatically display here. See en.wikipedia.org/wiki/WP:REFB for instructions on how to add citations. --> {{reflist}}

{{Nieuport V-strutters}} {{World War I Aircraft of the Central Powers}} {{Idflieg D-class designations}}

Category:1910s German fighter aircraft Category:Sesquiplanes Category:Rotary-engined aircraft Category:Aircraft first flown in 1916