[2] Intended to replace the SZD-8 Jaskółka as the Polish team mount at the World Gliding Championships in 1958 in Leszno, the SZD-19 Zefir was a high-wing glider with a wooden and glass-fibre fuselage, retractable undercarriage and all-metal wings incorporating hydraulically actuated flaps.

The first prototype SZD-19X Zefir flew on 31 December 1958, missing the 1958 championships, but the flight tests revealed problems with control and stability as well as operation of the flaps and complexity of the hydraulic system.

Two SZD-31 Zefir 4's competed in the 1968 World Gliding Championships at Leszno with mediocre (mainly due to the unrecognized issue of an air leak through airbrake housings) results - they took 14th and 28th place.

[2] All these inconveniences were the result of the design striving to squeeze every possible bit of performance (hence i.e. narrow cockpit with uncomfortably prone pilot position), handling comfort was considered second.

[2] Data from The World's Sailplanes:Die Segelflugzeuge der Welt:Les Planeurs du Monde Volume II [4][7]General characteristics Performance