"PZL (Państwowe Zakłady Lotnicze - State Aviation Works) was the main Polish aerospace manufacturer of the interwar period, and a brand of their aircraft. Based in Warsaw between 1928 and 1939, PZL introduced a variety of well-regarded aircraft, most notably the PZL P.11 fighter, the PZL.23 Karaś light bomber, and the PZL.37 Łoś medium bomber.
In the post-war era, aerospace factories in Poland were initially run under the name WSK (Transport Equipment Manufacturing Plant), but returned to adopt PZL acronym in late 1950s. This was used as a common aircraft brand and later as a part of names of several Polish state-owned aerospace manufacturers referring to PZL traditions, and belonging to the Zjednoczenie Przemysłu Lotniczego i Silnikowego PZL - PZL Aircraft and Engine Industry Union. Among the better-known products during this period is the PZL TS-11 Iskra jet trainer and PZL-104 Wilga STOL utility aircraft." - (en.wikipedia.org 30.01.2020)
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