The spinning pins nozzle: a new controlled droplet applicator for aircraft

Abstract

This information relates to improvements in devices for delivery of spray droplets from aircraft or ground vehicle. The application of pesticide using aircraft remains a vital part of modern agricultural systems, but the problem of associated off-target transport or spray drift is receiving increasing attention. Research carried out by Craig et al 1998a has demonstrated that spray drift depends upon the size of droplets in the spray and also the width of the droplet size distribution or spectrum. Buffer distances of several hundred metres are often required to reduce aircraft spray drift deposition to acceptable levels. Such large distances are inconvenient and uneconomical in most cropping situations. The present approach is to significantly reduce spray drift by developing a new nozzle which utilises large droplet Controlled Droplet Application (CDA) technology. This would produce a spray with a narrow droplet size distribution and reduce the number of driftable fines, and also the number of excessively coarse droplets which constitute waste.