Zeppelin-Lindau D.I

The Zeppelin-Lindau D.I, also named the Zeppelin D.I (Do) in German documents and the Dornier D.I after the war, was a single-seat all-metal biplane fighter with cantilever wings and a stressed skin monocoque structure, developed by Claude Dornier while working for Luftschiffbau Zeppelin at Lindau. It came too late for operational service with the German air force in the First World War. It was the first fighter with such a construction, and an external fuel tank, possibly jettisonable, reduced the danger of fire in flight. Seven prototypes were built. German air force pilots evaluated the type in May and June 1918 and again in October, reporting heavy aileron controls and poor climb at altitude, and the ace Wilhelm Reinhard was killed on 3 July 1918 after a structural failure. With a more powerful BMW IIIa six-cylinder engine the climb to 5,000 metres fell from 25 to 13 minutes, an order for 50 followed, and these were about half complete when production stopped after the armistice. One example each went to the United States Navy and Army for study. The Dornier Do H Falke monoplane was developed from it.