Siemens - Schuckert D . I The Siemens - Schuckert D . I was a single - seat fighter built by Siemens - Schuckert Werke in 1916 . It was a German copy of the French Nieuport 17 that was obsolete by the time it was available in numbers , so that it served mainly as an advanced trainer . Design and development . The French Nieuport 17 fighter , which reached the front in March 1916 , established such ascendency over existing German fighters that captured examples were supplied to several German aircraft manufacturers with a request to " study " the type . The Siemens - Schuckert Werke produced the D . I , based very closely on the Nieuport . The most important difference from the Nieuport 17 was the powerplant - instead of the Le Rhone 9J of the Nieuport ( licenced and un - licenced versions of which were actually available in Germany at the time ) , Siemens - Schukert chose to use their own 110 hp ( 82 kW ) Siemens - Halske Sh . I rotary engine - in which the cylinders and the propeller rotated at 900 rpm " in opposite directions " : producing an effective 1800 rpm . Visually , the effect of this was that in place of the Nieuport 17 ' s circular , fully " closed " cowling the D . I had a small , close fitting , semi - circular cowling with an open bottom , to allow adequate cooling for the slow revving Siemens - Halske . This gives some photographs of the type the appearance of the earlier Nieuport 11 . The wing area ( 14 . 4m² ) was a little less than the famous 15m² of the Nieuport - the gap between the wings was reduced slightly , and the interplane struts were of steel tube , with broad wooden fairings , in place of the well - known tape bound struts of the original . Production history . An order for 150 aircraft for the " Luftstreitkräfte " was placed on 25 November 1916 , but initial deliveries were slow , due to production difficulties with the complicated geared engines , so that the type was not available for service until well into 1917 , by which time many " Jagdstaffeln " were already equipped with the very much superior Albatros D . III . A backup order for a further 100 machines , placed on 21 March 1917 , was cancelled , and only 95 were produced in total . Late production models were fitted with modified tailskids , and had large pointed spinners on their propellers . Operational History . The S . S . W . D . I was obsolete before it was available in numbers , so that most of the examples produced were sent to the fighter training schools , although a few " Jastas " received one or two examples during 1917 . The type is poorly documented - in particular no reliable details are available for its performance : the published figures are essentially those of the Nieuport 11 , whereas such a close copy of the 17 , with a powerplant of similar output , might have been expected to have a performance roughly equivalent to that of the original from which it was derived . Variants . A single D . Ia was produced with a greater wing area - two examples of the D . Ib had a higher compression version of the Siemens - Halske Sh . I . Neither was ordered into production . Development continued through a series of D . II prototypes to the Siemens - Schuckert D . III .