triangular fin carrying an upright, straight edged balanced rudder which was slightly angled below the heel and extended down to the keel. The Prüfling landed on a rubber sprung skid below the whole forward, ply skinned fuselage, assisted by a very small tailskid. It first flew in 1926 and was soon in use with the RRG related Rhön and Rossitten gliding clubs. Plans were sold and many were built inside and outside Germany. As examples, one was flying with the Lancashire Aero Club and another with the London Gliding Club in the early 1930s. Despite such success, the Prüfling was something of a disappointment as a secondary training aircraft, for its performance was not much better than typical primaries. Its handling was also not good, with a lack of inherent stability. Lippisch returned to the design of secondary gliders four years later, after exploring tailless types, resulting in the RRG Falke. A Prüfling was the first glider used by the United States Navy. A single German-made aircraft was purchased from a U.S. civil glider school, assigned serial number A8546, and used for airship launch tests; the first such launch was made from USS Los Angeles (ZR-3) on 31 January 1930. The Prüfling was never assigned a formal U.S. military aircraft designation. Operators United States Navy Specifications References 1920s German sailplanes Aircraft first flown in 1926 Glider aircraft High-wing aircraft Military gliders