The idea of installing the Junkers Jumo 213A engine (which had mainly been used in bombers until then) into the Focke-Wulf 190 airframe arose as an attempt to improve the aircraft's performance at high altitudes. The A and F versions indeed showed a significant loss of speed above 7,000 meters. Armed with two 20-mm and two 13-mm cannons, the D-9 was immediately appreciated by pilots, who regarded it as an opponent on par with the P-51 Mustang. In its secondary role of ground attack, the Dora 9 also distinguished itself during Operation Bodenplatte, the last offensive of the Third Reich in the Ardennes. The production of the D version is estimated at 650–700 units, of which four have survived to this day.