[2] As designed, the R.IV was a large three-bay biplane with unstaggered wings of unequal span and a fully enclosed cabin.
[6] The main undercarriage consisted of divided units, each of which carried dual wheels, and the tail was supported by a pair of tailwheels.
[2] The fuselage was forked into an upper and lower section, which allowed a clear field of fire to the rear of the aircraft.
[2] It was used operationally until Rfa 501 was redeployed to the Western Front, at which point it was left behind in Vilna for use as a trainer with the Riesenflugzeug Schulabteilung ("giant aircraft training unit").
These serials were changed on 13 July 1915 to G.33/15 - G.38/15, for unknown reasons and again on 6 November 1915 to R.2/15 - R.7/15 in the R (Riesenflugzeug - giant aircraft) series, adopting the R.II to R.VII designations.