Tianjin Port Free Trade Zone has issued a number of measures to support and encourage the development of aviation bonded maintenance and remanufacturing industry in the airport area of Tianjin Free Trade Test Zone, covering many fields, such as airworthiness testing, aviation maintenance, bonded warehousing, "passenger modification", qualification certification and customs clearance facilitation. "measures" will give full play to the advantages of Tianjin Free Trade Experimental Zone bonded function. The policy dividend is used to support the development of domestic and foreign aviation maintenance enterprises and upstream and downstream industries, and to further enhance the international competitiveness of aviation maintenance industry.