01/31/2011. Remarks by Claudio Delfini: "The Soviet fighter Yak-9, in the version Yak-9D, Yak-9M and Yak-9T formed the nucleus of the four Polish AF regiments fighting on the Eastern Front in the spring of 1945. The post-war Yak-9P was the final piston engine powered version of the Yak fighter aircraft, powered by the 1,650 hp Klimov VK-107A twelve-cylinder liquid-cooled V-engine.

The first ten Yak-9P fighters were introduced to the 1st Warszawa AF Fighter Regiment in November of 1947. During the late 1940s and into the 1950s the Yak-9P was the standard plane in the Polish AF, where it served as a bomber-fighter. On September 1, 1949 of the 170 Yak-9s in service in the Polish AF, a total of 93 were Yak-9Ps. The pictured aircraft was used by the 1st Warszawa."