Interesting plane.
The first polish serial production aircraft after WW2, the Szpak-4T, produced in a series of 10 planes.
Designed by LWD (Lotnicze Warsztaty Doświadczalne = Aviation Experimental Workshops), manufactured by PZL (Polskie Zakłady Lotnicze = Polish Aviation Works), formerly "WSK" (Wytwórnia Sprzętu Komunikacyjnego = Communication Equipment Factory) in Mielec, simply called "PZL Mielec".
The engine was a pre-WW2 german Bramo manufactured Siemens-Halske Sh.14A-4, the engine series which also powered famous planes like the Focke-Wulf Fw 44 "Stieglitz", the Bücker Bü-133 "Jungmeister", the first fully controllable helicopter Focke-Wulf Fw 61 and the Flettner Fl 282 "Kolibri" Synchropter.
Mike