Characterization of a new ultra-low volume fuselage spray configuration on Air Force C-130H airplane used for adult mosquito control.

The US Air Force (USAF) tested a new fuselage boom configuration on the C-130H airplane. We used into-the-wind and crosswind field trials to characterize a BVA oil (BVA Inc, Wixom, MI) droplet spectra produced by fuselage booms with flat-fan nozzles (8001, 8005) at the Air Force Range at Avon Park, FL. Across all trials, median droplet diameter (DV50) for 8001 and 8005 nozzles were 11.4 microm and 54.3 microm, respectively. For 8005 nozzles 22% of droplets collected were 7 microm to 25 microm size range while 75% of droplets from 8001 nozzles were < 7 microm. Fuselage configuration parameters and field data were also used as input variables into the Agricultural Dispersal (AGDISP) computer model to predict aerosol deposition and droplet fate. AGDISP predictions were compared with field data from crosswind tests and the model was found to fit reasonably well to empirical data. However, AGDISP predictions were better correlated with empirical findings for larger droplets than smaller droplets and for locations closer to the release point than further downwind.