The P.50 was designed under the leadership of Wslewolod Jakimiuk as a successor to the PZL P.11. The first prototype, the P.50/I, made its initial flight in February 1939, powered by an 840 hp Bristol Mercury engine and armed with a quartet of wing mounted 7.92 mm Wz 36 machine guns. An initial batch of 30 examples, designated Jastrzab A, were under construction at the time of the invasion.
A second prototype was intended to serve as development aircraft for the more advanced Jastrzab II. Designated P.50/II, this featured a revised rear fuselage, a pair of 20mm cannon supplementing the machine guns, pilot armour and fitment for a 1,375 hp Bristol Hercules engine, which had not been installed at the time of the German assault. [N 2]
The first prototype was shot down during the invasion by Polish AA gunners, who assumed the aircraft was German.
- Details relate to the Jastrzab A. Performance figures are estimated
- Production examples of the P.50/II were intended to have a 1,200 hp P.Z.L. Waran radial engine.