The J -20 is a future heavy fighter designed by Chengdu Aircraft Design Institute of China and manufactured by Chengdu Aircraft Industry Company of China, which is used to replace the third generation air superiority/multi-purpose fighters such as J-10 and J-11. This fighter will be responsible for the maintenance of our army's sovereignty over the air and sea in the future. According to the standards of China and NATO, this aircraft is the "fourth generation fighter/fighter" (Note: Russia and western countries have different standards for the algebraic division of fighter. Take the J -20 as an example. Western countries call it the fourth generation aircraft, while Russia calls it the fifth generation aircraft), and its purpose is to meet the operational environment needs of China Air Force after 2020.