The Fw 190D "long-nose" version was an adaptation of the radial-engined Fw 190A to the Junkers Jumo 213 twelve-cylinder liquid-cooled engine. In many respects, the "Dora" was the most successful version of the Focke-Wulf fighter to attain service in quantity. In 1943, the Luftwaffe was faced with a desperate need for fighters with better high-altitude performances to face the threat of Allied bombers. By that time, the Luftwaffe was aware of the existence of the B-29, and they were also aware that the existing Fw 190 would be incapable of effectively intercepting this American bomber at the altitudes at which it was supposedly capable of operating. Consequently, Dipl.-Ing. Kurt Tank undertook the development of a high altitude version of his Fw 190 fighter to meet the threat. Delivery of the Fw 190D-9 began in August 1944. The first Gruppe to convert to the "Dora-9" was III/JG 54. Their initial assignment was to fly "top cover" for Me 262 jet fighters during takeoff when the jet fighters were specially vulnerable because of their poor acceleration. At first, Luftwaffe pilots were somewhat suspicious of their new fighter, since the Jumo 213 was thought to be only a "bomber" engine. However, it soon became apparent that they had a winner on their hands. The "Dora" could out-climb and out-dive its BMW 801-powered predecessor with ease, and it possessed an excellent turning rate at speed. An experienced pilot could pull a tighter turn in a D-9 than he could with the BMW-powered FW-190A. The general opinion of the pilots who flew the FW 190D-9 was that it was the finest propeller-driven fighter available to the Luftwaffe during the entire war. In fact, many of its pilots considered it more than a match for the redoubtable P-51D Mustang | 
