RRG Prüfling

Prüfling
Role	Secondary training glider
National origin	Germany
Manufacturer	Rhön-Rossitten Gesellschaft (RRG)
Designer	Alexander Lippisch and Fritz Stamer
First flight	1926

The 1926 German RRG Prüfling (English: Examinee) of 1926 was a secondary training glider designed for club use. Plans were sold and it was built in Germany and across the world.

Secondary gliders were meant to be used by student pilots after an introduction to flight on very simple primary gliders. Both types needed to be cheap to build, given the difficult financial position of many Germans after World War I and also simple enough that skilled amateur builders, both within and without gliding clubs, could successfully construct them from plans. The primary/secondary glider concept took shape shortly after the absorption of the Martens gliding school on the Wasserkuppe into Rhön-Rossitten Gesellschaft (RRG) at the end of 1925. Martens chief instructor Fritz Stamer and Alexander Lippisch were brought together to produce two such gliders and within a few days the Zögling (English: Pupil) and the Prufling designs were complete. Some parts, for example the wings and to a lesser extent the horizontal tails, of the two aircraft were similar.

Both had almost rectangular, two-spar, wooden structured, two piece wings with fabric covering everywhere except the leading edges, which were plywood covered. The Prüfling's wing tips were more rounded and its span 500 mm (19.7 in) greater. They both had simple ailerons reaching to the tips, where they were cropped, though the Prüfling's were a little longer. Both had triangular tailplanes, carrying elevators that were rectangular apart for a cut-out for rudder movement, though the Prüfling's tailplane was more strongly swept and was broader in chord.

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