The PZL.48 Lampart (leopard) was a Polish heavy fighter-bomber design, that remained only a project, owing to the outbreak of World War II.
General characteristics Performance Armament |} The PZL.54 Ryś (lynx) was a pre-war Polish heavy fighter design developed in 1939 by the PZL company.
Although intended as an evolution (and a replacement of) the PZL.48 Lampart, it never went beyond drawing boards due to Invasion of Poland and the outbreak of World War II.
The aircraft was to be equipped with more powerful Hispano Suiza 12Z inline engines, and was slated to become one of the basic fighter-bombers of the Polish Army.
The aircraft was to be an all-metal (duraluminium) low-wing monoplane, with a classic retractable landing gear and a fixed tail wheel.
The aerodynamic profile was based on the highly successful PZL.37 Łoś bomber, including the double tail fins.
While the design looked promising, the PZL.54 was based around the new Hispano-Suiza engines that at the time were still under development and could deliver only 1000 out of planned 1600 horsepower.