Built as licensed Yak-11 in LET Kunovice. As C-11 in Czechoslovakia air force 1955-1964, after army duty AK Mladá Boleslav 1964-1980 as OK-JIL. In 2018 again airworthy after engine overhaul. The C-11 is now in c/s from 1. letka/18. slp at Pardubice AFB.