Originally, it was planned to convert all the 41 remaining M.S.406s and M.S.410s with the Soviet engine, but it took time, and the first front-line aircraft of this type did not reach LeLv 28 until July/August 1944. By the end of the Continuation War in September 1944, only three examples had been converted (including the original prototype). Lieutenant Lars Hattinen (an ace with six victories) scored three kills with the Mörkö-Morane, one with each Mörkö-Morane in the squadron. More fighters arrived from the factory, though, and the Mörkö-Moranes took part in the Lapland War as reconnaissance and ground attack aircraft. Not all the Mörkö-Morane conversions were completed before March 1945, when the entire re-engining programme was halted. After the end of the war, the total was brought to 41, which served as advanced trainers with TLeLv 14 until September 1948. In 1952 all remaining Finnish Moranes were scrapped.