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In recent years, the plant protection UAV sustained development quickly.Agricultural aviation spraying is one of the main project of agricultural aviation services, due to the lack of equipped with national power, currently, resulting in the payload of domestic plant protection UAV generally less than 20 kilograms, the payload is limited, sustained flight time is short, and the number of landings is more.Therefore, increasing carrying capacity is the development trend of UAV in the field of plant protection.Tensairity is a lightweight combined structural system composed of low internal pressure air-beam, tender cable and stiff upper chord.A new structure with Air bag and Zhang Xian liang structure ,has the characteristics of light weight, high erection speed, small volume, strong bearing capacity, low construction cost and so on.Tensairity is simple with each element under specific load.The air-beam exerts pre-stress for the cable-strut structure with its inner pressure.It also functions as the continuous in-plane support for the stiff upper chord.The buckling load capacity of the upper chord is enhanced while its in-plane calculation span is reduced.The stability problem of struts has been avoided because they are replaced by the air-beam.Tensairity makes the best use of the stiff, tender and pneumatic elements.It is a self-support and self-balance system.It is convenient for fabrication, transportation and construction.It has a bright future.At present, in international, Swiss Air light.Ltd and EMPA combination structure research center have carried out relevant research work, in the domestic ,Harbin Industrial University ,Cao Zhenggang ,had make some research ,mainly from the theoretical analysis, model test and numerical simulation.In this paper ,we introduced the Zhang string structure, string structure of flat piece, large span structure and application, the membrane structure concept, types and development ,and based on this, we discusses the development status and application situation of Tensairity in the domestic and foreign, summarized the advantages of Tensairity.At the same time, we generalized the existing problems in safety, wind resistance,resources, etc.discussed the development trend and research significance of the Tensairity.At present, Tensairity is mainly used in large span space structure, can also be used in the field of the non-architectural engineering field, such as in large airship, light aircraft, surface buoyancy structure, space explorer.Although Tensairity has applied in the project, and verify the applicability and feasibility, it is still in the initial stage of research, especially has not been applied in the field of agricultural plant protection UAV.It needs further research.If it will be introduced into the field of agricultural aviation, and is propitious to control agricultural pest better, to achieve accurate operations, the agricultural aviation industry in China will be healthy, orderly and rapid development.