J-7 (Chinese Code: J-7, English: Chengdu J-7 / F-7 fighter aircraft, NATO Code: Fishbed, translation: fish nest) fighter is a single seat single engine supersonic jet developed by Shenyang aircraft factory in 1960s. The J-7 is an imitation of the Soviet MiG-21 ?-13. After that, the aircraft was transferred to Chengdu aircraft factory and Guizhou aircraft factory for subsequent improvement and mass production.The J-7 is the first two times sonic jet fighter developed by China. It is equipped with a large number of Chinese air force and navy air force, mainly used for land air defense and seizing the front-line air control right in the battlefield. It can also carry out ground attack missions. It is a typical second-generation fighter. The technical features of J-7 are high altitude and high speed, light, small and flexible, low cost, high efficiency and simple use and maintenance [1]. J-7 fighters have been exported to many countries in batches [2].