A biplane Fokker airliner? Yes and no - the substantial lower wing of the F.V (F.5) could be removed and it could be operated as a monoplane, although as such it looked dangerously incomplete. Only this example was built and it was tested for two weeks by the German-Russian airline Deruluft, carrying the Russian registration RR13. It became H-NABW in March 1924, and shortly thereafter it was exported to Austria. Photo from: ETH-Bibliothek Zürich