Payload Capacities of Remotely Piloted Aerial Application Systems Affect Spray Pattern and Effective Swath

Production agriculture has recently witnessed exponential growth in the use of UAS technology to obtain site-specific, real-time spectral reflectance data for the management of spatial and temporal variability in agricultural ecosystems. The integration of this novel technology and remotely piloted aerial application systems (RPAASs) for pest management requires data curation on spray pattern uniformity, droplet distribution and the operational factors governing such data. The effects of application height and ground speed on spray pattern uniformity and droplet spectra characteristics for four commercially available RPAAS platforms configured with four different payload capacities (5, 10, 15 and 20 L) and factory-supplied nozzles were investigated. Spray pattern was determined by a cotton string deposition analysis system. Spray droplets captured on water-sensitive paper cards were analyzed using a computer-based scanner system. The test results indicated that each RPAAS platform of varying payload capacity was able to produce an acceptable spray pattern. As the payload capacity increased, so did the effective swath. However, the effective swath was comparable between 15 and 20 L units. The theoretical spray application rate decreased with ground speed. The fundamental data reported here may provide guidance to aerial applicators and help in the furtherance of RPAASs as an effective pest management tool.