An aerial ULV spray system was developed for use with a Grumman Ag-cat using Dibrom 14 (1,2 dibromo-2,2-dichloroethyl dimethyl phosphate). The entire system utilizes a 26 volt electric motor directly coupled to a brass gear pump. The design affords simplified attachment and changeover from the conventional system, an incorporated flushing system, pressure gauges located at the nozzles, disposable insecticide tank, and safety for the pilot from insecticide exposure. The system was calibrated and field tested to determine flow rate, swath width, particle size, and its ability to kill mosquitoes. The system has proven to be a valuable tool in combating Culex salinarius (Say) and Aedes sollicitans (Walker).