The very first enemy plane shot down during the Korean War was by a WWII F-51D Mustang! Throughout the Korean War many WWII aircraft distingushed themselves with their accomplishments. These propellor-driven airborne weapons were seen as obsolete, relics of an older era, but these feisty planes not only held their own against the jets of the Korean War era, they were Korean War heroes in their own right.
Over the course of the Korean War, however, it became obvious that the day of the piston-engined fighter was coming to a close and that the future would lie with the jet fighter. The first operational jets were developed during World War II and saw combat in its final year (1945). The German Me-262, developed by Messerschmitt was the only jet fighter to see actual combat during WWII. The Americans were one of the first to begin using jet fighters post WWII, the Lockheed P-80 Shooting Star (soon re-designated F-80) was the first jet fighter to see combat after WWII.
Soon after the introduction of the F-80 Shooting Star, the F-86 Saber was introduced to combat the Mig 15, entering the swept wing fighter into the history books. Propellor-driven aircraft went quietly into the night, but have never been forgotten!