Karl Schopper, who proceeded to strengthen the structure and replace the Union G.Is troublesome inverted engines with upright Mercedes D.IIIs.

[1] Flight trials commenced late in 1915 with relatively few engine problems but the structure had to be strengthened several times and three wing arrangements were also tested between 1915 and 1917.

[1] The airframe of the R.I and R.II was typical of large German aircraft of the time, with a wooden fuselage and metal wings covered with fabric.

The undercarriage comprised a twin nose-wheel assembly, four main-wheels spread between the engine nacelles on the lower wings and a tail-skid.

[1] Poor performance and competition from similar aircraft precluded production, but at least one R.I and two R.IIs were accepted by Idflieg and test flown until the middle of 1917.