High Quality Content by WIKIPEDIA articles! The Polikarpov ITP (Istrebitel Tyazholiy Pushechniy; Russian: Истребитель Тяжелый Пушечный; Heavy Cannon Fighter) was a Soviet fighter prototype designed during World War II. Development was prolonged by the evacuation of the design bureau forced by the German advance on Moscow in the fall of 1941. By the time the second prototype was finished the Soviets had fighters with equivalent or better performance already in production and the program was cancelled.