The FW-190 is widely regarded as Germany's best fighter aircraft of WWII. Its appearance in the skies over France in early 1941 was a rude shock to the Allies, as it was clearly superior to any other plane. For nearly a year, until the debut of the Spitfire IX, the FW-190 was the unmatched champion of the air war. As the war progressed, the FW-190 was developed into many variants as a pure fighter, a ground-attack fighter/bomber, and as a close-support aircraft. No fewer than 40 different versions were produced, with different combinations of engines, armament, wings, systems, and roles. First flown on 1 June 1939, the FW-190 served for the duration of the war, largely replacing several other types in the process, including the Junker JU-87 Stuka dive bomber. Allied bombers dreaded the sight of these potent aircraft, as did the fighters who provided cover for them. Arguably, the FW-190's greatest impact on the Allied war effort was to spur ever-greater advances in technology and aircraft design to counter its threat.