 It was flown only in February or March 1939 and also did not meet expected performance (estimated maximum speed was 520 km/h, while it hardly reached 465 km/h).It was also too heavy (2155 kg instead of 1715 kg) and had too small useful load.Because of these facts, further development of PZL.38 "Wilk" aircraft and "Foka" engine was abandoned in the Spring of 1939, in a favour of the new construction PZL.48 "Lampart" - which was a modification of "Wilk" with radial engines.