It is a Polish experimental tailless glider designed by Wladyslaw Nowakowski and Justyn Sandauers of SZD (Szybowcowego Zakladu Doswiadczalnegoce - Establishment of experimental gliders). The SZD-6X performed its first flight on January 5, 1951, at Katowice, with Adam Zientek to the controls.
Only one prototype built.
It was followed by the SZD-13X "Wampir" a tailless glider project designed by engineer Irena Kaniewska, then by the SZD-20X "Wampir 2" designed by Jan Dyrek. first flight in 1959.