The Zeppelin-Lindau Rs.IV (known incorrectly postwar as the Dornier Rs.IV) was a Riesenflugzeug (Giant aircraft) monoplane all metal flying boat with a stressed skin hull and fuselage developed for the Imperial German Navy to perform long range patrols over the North Sea. It had been developed by Claudius Dornier while working for Zeppelin in the town of Lindau.