Deutsche Forschungsanstalt Für Segelflug

The Deutsche Forschungsanstalt für Segelflug, or DFS (German Research Institute for Sailplane Flight or German Institute for Glider Research) was formed in 1933 to centralise all gliding activity in Germany, under the directorship of Professor Georgii. It was formed by the nationalisation of the Rhön-Rossitten Gesellschaft (RRG) at Darmstadt.

The DFS was involved in producing training sailplanes for the Hitler Youth and Luftwaffe, as well as conducting research into advanced technologies such as flying wings and rocket propulsion. Notable DFS-produced aircraft include the DFS 230 transport glider (1600+ produced), the German counterpart to the British Airspeed Horsa glider, and the DFS 194 similar to the famous Messerschmitt Me 163 rocket fighter.

In 1938, following a fatal accident at the Wasserkuppe, DFS held a competition to design a more effective speed brake for gliders. The final design, produced by Wolfgang and Ulrich Hütter of Schempp-Hirth, is used to this day and generally referred to as the "Schempp-Hirth brake".

(note the two lists have not been synchronized (i.e. not all planes on both lists))

The modern DLR still does research into gliding flight, as the DFS once did - evidence of this is their enlarged 17-meter wingspan Glaser-Dirks DG-300 Elan high-performance glider, used to precisely set and measure comparative glider performance parameters.

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Wikipedia