Today, I would like to share with all colleagues in the industry some application research in flight prevention carried out by kingyu in recent years. Firstly, the development history and current situation of flight defense are introduced.

　　In 2019, the total area of flight control operations in China is expected to exceed 450 million mu. In 2018, the number was 270 million mu. According to incomplete statistics, the number of UAVs for plant protection in China is expected to exceed 50000, compared with 30000 last year. From the data comparison, it can be seen that both the number of UAV operations per mu or the number of UAVs indicates that China has entered a new era in the development of aviation plant protection. There is no doubt that flight prevention has become a third mainstream method of spraying after artificial application and mechanical boom sprayer.

　　The above map shows the application degree distribution of UAVs in various regions of China. There are obvious ladder distribution. This first depends on the ability of local farmers to accept new things. The second is that the cost of aerial control can be accepted in the areas with shortage of human resources. Third, such as Heilongjiang, Xinjiang and other sparsely populated areas, UAVs help to improve operational efficiency.

　　The rapid development of UAV in China, an important internal driving factor is the change of rural labor structure. In the traditional understanding, China is a country enjoying the demographic dividend. In fact, China's rural labor force structure has undergone essential changes. It is inevitable for China to enter the aging population. Especially in the southeast coastal provinces such as Jiangsu and Zhejiang, the proportion of rural young and middle-aged labor force going out to work is relatively large.

　　Secondly, it is related to the implementation of land circulation policy. Land concentration is more suitable for UAV operation mode. At present, such as Nantong, Yancheng and other places in Jiangsu Province, the land transfer is relatively fast, and some large growers have 3500 mu or even thousands of mu.

　　The third is the "double reduction" plan proposed by the Ministry of agriculture, and the policy requirement of "zero growth" of pesticide and fertilizer. The waste of liquid medicine by UAV is relatively small.

　　The exploration of flight prevention in domestic agricultural and chemical enterprises started relatively early, but the road ahead was relatively tortuous. It can be said that this is due to the early aircraft did not meet the requirements of plant protection application, subject to the technical bottleneck of pesticide application machinery, the development of UAV flight prevention has been relatively slow. It was not until 2016 that the development of UAV flight defense came into being.

　　The differences of aviation plant protection at home and abroad mainly lie in the number of mu of control and drug load, corresponding to the different degree of land concentration in different countries.

　　The important difference between UAV and conventional spray is water consumption per mu and spray height. The UAV has the advantages of fast spraying speed, less water consumption, high concentration and high flight altitude, which results in the interference of wind. Therefore, the ability of anti drift should be considered properly when the chemicals are developed and mixed with the later barrels. At the same time, because the forward speed of flight is much higher than that of artificial application, how to make the liquid effectively deposit on the target surface is a scene factor that we need to consider when developing.

　　In recent years, the national, local or enterprise industry associations have issued a lot of guidance requirements for the standardization of flight prevention operation. Flight control additives become a very important standard in the flight prevention package.

　　In this regard, Heilongjiang Province has taken the lead in formulating the UAV operation standards, mainly for the meteorological conditions of flight control operation, making a good specification. Codewa also jointly issued the joint flight prevention standard with Dajiang.

　　In April 2019, in Jianhu, Jiangsu Province, the group standard and flight controller training meeting of plant protection UAV series should be the largest semi official meeting of our industry association. The group standard of flight prevention was proposed for the first time at the meeting. The three group standards are relatively valuable and have specific requirements on Meteorological conditions, operation requirements and route planning Please.