Yakovlev Yak-11Yak 11 airplane model. Sometimes equated with the North American T 6 trainer in terms of its widespread use, 3,859 basic Yak 11s were produced through 1956. Although production then ceased in Russia, it continued in Czechoslovakia, where it had been licensed to LET in 1953 with the designation C. 11. An additional 707 of those aircraft were manufactured by LET. Many of the Yak 11's still operational in the USSR were replaced in 1958 by the Yak 11U, a