Aachen FVA 4 Pipo
The need to build a simple and easily repairable aircraft for beginner training had been identified by the FVA. It began in the years 1923/24 to emerge that the older FVA members moved away after completing their studies from Aachen and the newly added students were usually not former wartime pilot and thus could not fly. Also, Klemperer, who was primarily responsible for the successes of the FVA, had emigrated in 1924 in the United States. Performance in the 1922 Rhön competition had been unsatisfactory.
Building of the FVA4 "Pipö" and the FVA5 "Rheinland" began in 1923. The FVA4, a simple, motorised biplane, for the training of new young pilots of the FVA.
The FVA-4 received the nickname of the sister of Professor von Kármán the name "Pipö".