siemens-schuckert's first production fighter aircraft was the siemens-schuckert d.i, which was based closely on the french nieuport 17. apart from the use of the siemens-halske sh.i, a geared rotary engine in which the crankshaft and the propeller rotated in opposite directions, the d.i was in fact a fairly close copy of the nieuport. by the time production d.is appeared in 1917 however, the design was no longer competitive and after 95 had been built, production was cancelled, with the type serving mainly as an advanced trainer.