MiG alley

"MiG Alley" was the name given by United Nations (UN) pilots to the northwestern portion of North Korea, where the Yalu River empties into the Yellow Sea. During the Korean War, it was the site of numerous dogfights between UN fighter pilots and their opponents from North Korea (including some unofficially crewed by Soviet airmen) and the People's Republic of China. Soviet-built Mikoyan-Gurevich MiG-15 were the aircraft used during most of the conflict, and the area's nickname was derived from them. It was the site of the first large-scale jet-vs-jet air battles, with the North American F-86 Sabre.

The North Koreans began their war against South Korea on June 25, 1950 with small numbers of Soviet aircraft retained from the Second World War. These were flown by under-trained and inexperienced pilots. After the United States and its closest allies committed its air units to the UN, the North Korean People's Army Air Force (KPAAF) was rapidly depleted. For several months, propeller-engined bombers and fighters, like the B-29 and P-51 Mustang – and early jet fighters like the F-80 Shooting Star, F-84 Thunderjet and Grumman F9F Panther – flew the skies over Korea virtually unopposed.

During October, the major Communist powers – China and the Soviet Union – commenced unofficial military support of North Korea. The Soviets also committed to supply North Korea and China with its latest MiG-15 fighters, and to train Korean and Chinese pilots to fly them. China officially entered the war in support of North Korea on October 25, 1950. While its strength in ground forces initially overwhelmed UN forces, the Chinese Peoples Liberation Army Air Force (PLAAF) was, at the time, small and no better equipped than the KPAAF.

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Wikipedia