The SZD-20x Wampir II (Szybowcowy Zakład Doświadczalny - Glider Experimental Works) was a single-seat tail-less research glider designed and built in Poland from 1959.
| SZD 20x Wampir 2 | |
|---|---|
| Role | Glider |
| National origin | Poland |
| Manufacturer | PZL Bielsko |
| Designer | Jan Dyrek |
| First flight | 9 September 1959[1] |
| Number built | 1 |
The SZD-20X Wampir II (vampire II) was designed to compare a flying wing designed to Standard class rules with a more conventional standard class glider. Main designer was Jan Dyrek. Based on experience with the earlier SZD-6X Nietoperz and SZD-13 Wampir tail-less gliders, the SZD-20X was an all wood flying wing, with the pilot sitting in a pod extending aft of the trailing edge on the centreline, and large swept fins & rudders at approx 2/3 span on each wing.
The SZD-20X was associated with the number 15, having a 15m span, aspect ratio of 15 and wing area of 15m², whether this was by design or accident is not known.[1] Early flight trials commenced with hops towed behind a car to test control responses, followed by an aero-tow launch on 9 September 1959, piloted by Adam Zientek. Flight trials revealed a marked sensitivity to turbulence resulting in flutter, and during trials at stalling speed, the SZD-20X entered a spin, which the rudders were unable to recover the aircraft from, only when the pilot shifted his weight as far forward as he could, did the SZD-20X recover from the spin.[1] Flying in the SZD-20X continued until 6 October 1959, when turbulence-induced flutter tore the aircraft apart, the pilot escaping with parachute.[1]

Data from The World's Sailplanes:Die Segelflugzeuge der Welt:Les Planeurs du Monde Volume II[1][2]
General characteristics
Performance
Aircraft of comparable role, configuration, and era
Related lists
| Wikimedia Commons has media related to SZD-20 Wampir 2. |
Polish post-1945 gliders | |
|---|---|
| Instytut Szybownictwa | |
| Szybowcowy Zakład Doświadczalny / PZL Bielsko-Biała / Allstar PZL Glider |
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| Politechnika Warszawska | |
| Margański & Mysłowski | |
| PZL Krosno | |