Abstract:
Aerial electrostatic spraying system is the specialized application of conventional electrostatic spraying technology over the air operating platform. It plays an important role in aerial plant protection technology. Droplets with aerial electrostatic spraying can be adsorbed to the lower part of crop plants and the back of leaves as well as the front of the crop leaves. Aerial electrostatic spraying system is able to achieve disease and pest control and reduce environmental pollution with lower chemical application rate due to its uniform chemicals coverage, rapid droplet sedimentation, and low drift loss. The application of aerial electrostatic spraying system in agricultural production is an important part of aerial plant protection technology, which has attracted extensive attention of scholars in the world. When researchers originally developed aerial electrostatic spraying systems, the electrostatic spraying technology had been successfully applied in greenhouses, orchards and other ground spraying operations, which could significantly increase the droplet deposition on the target and reduce the drift to non-target areas. The United States is first country of the world to use an aircraft for pesticide spraying operations. For the experimental study on how to apply electrostatic spraying technology to aerial spraying equipment, the United States is also taking a leading role in this field. Research on aerial electrostatic spraying in the United States started in the 1960s. This summary is intended to detail this development process during the past 50 years and related test work, including early research on aerial electrostatic spray system, its continuous improvement, and the final determination of the prototype of the system. Aerial electrostatic spraying system can effectively reduce spray rate and increase spray droplet deposition, but it still has to face the challenges of improving the crop control effectiveness and reducing downwind spray drift. In addition, the application scope and optimum operating conditions of the aerial electrostatic spraying system for different crops and pests control require further research and exploration.Agricultural aviation industry has maintained great interests on aerial electrostatic spraying since the concept was first proposed. Laboratory test data of electrostatic spraying systems demonstrated a significant increase in the effect of droplet deposition and full coverage of leaves, but the droplet deposition and pest control results in field trials were not satisfied, and sometimes even lower than conventional spraying system. Nevertheless, the potential of aerial electrostatic spraying technology in increasing droplet deposition on the back of leaves and the reduction of chemical application rate shows that most technology has its scope of application and optimal operating conditions. Many factors affect the effectiveness of aerial electrostatic spraying operations. In addition, since the labelled application rate of most pesticides available in the United States is greater than that of an aerial electrostatic spraying system, it will be so difficult to maintain the required charge to mass ratio for an aerial electrostatic spraying system. The contradiction has hindered for the development of the aerial electrostatic spraying technologies. However, this also proved the advantages of aerial electrostatic spraying system from the other hand. The lower application rate per unit area can greatly improve the overall efficiency of aviation spraying operations in that one single flight sprays larger area of crops.China''s aerial electrostatic spraying systems in application mainly focused on introducing expensive overseas key equipment. Chinese researchers must research and develop aerial electrostatic spraying systems and accessories that work for our own conditions while introducing overseas technologies. It is proposed in this paper that the study of aerial electrostatic spraying technology in China should be combined with precision spraying and variable rate spraying technology to carry out related research and exploration.The great advantage of aerial electrostatic spray systems has established its place in the scheme of modern agriculture aviation. With continued experimental research and evaluation, modern aerial electrostatic spray systems will continue to support the agricultural aviation industry.