Aerial Application Using Unmanned Aircraft – A flight plan for success!! Brad Fritz USDA-ARS Aerial Application Technology Research Unit College Station, TX Damon Reabe National Agricultural Aviation Association

What is an Aerial Application? The FAA defines it has …the operation of an aircraft for the purpose of (1) dispensing any [pesticide, plant regulator, defoliant or desicant], (2) dispensing any other substance intended for plant nourishment, soil treatment, propagation of plant life, or pest control, or (3) engaging in dispensing activities directly affecting agriculture, horticulture, or forest preservation, but not including the dispensing of live insects.

So when an unmanned Aircraft performs a pesticide application is it an aerial application? ABSOLUTELY

What we know We know UAS manufacturers are marketing UAS’s for aerial application at scales equivalent to manned aircraft Our agriculture UAV crop dusters are a cost effective method to precision spray any liquid product on smaller acreage operations, up to whatever acreage you desire Individual spot spraying via hovering, or mass acreage cover up to any size you require, are all within our capability.

What we know “A User’s Guide for AgDRIFT 2.0.07: A Tiered Approach for the Assessment of Spray Drift of Pesticides” states – “… and fraction of driftable material (defined here as the fraction of volume containing drops less than or equal to 141 mm)” Current UAS’s carry very small payloads and use very small droplet sizes Smaller droplets = More pesticide drift

What we know More people at application site versus manned aircraft applications FAA requires a visual observer in addition to the pilot. Both are at the application site.

What we know Application rates of .13 GPA to 1.3 GPA. Far below minimum application rates required for non ULV aerial applications Current UAS spray setups are unable to deliver product per label instructions Optimum spraying heights exceed any altitudes listed in current crop protection labels

What we DON’T know Pesticide drift characteristics of UAV platforms Efficacy of droplet size What size is appropriate for AEZ Environmental and worker health impacts of additional fills due to small payload and presumably increased concentration of finished mix Environmental impact of distributing mixing and loading sites from containment systems at airports to uncontained systems in field

So how do we ensure safety? First we can’t make decisions based on assumptions Pesticide spray drift must first be researched prior to allowing UAS pesticide application A task force of the same magnitude of the Spray Drift Task Force needs to be assembled to conduct field research needed for all UAS platforms (Multi rotary wing, single rotary wing, fixed wing, mixed wing etc.) at speeds, altitudes and nozzle configurations aircraft will be operated in field Results will need to become part of AgDrift Model EPA can then perform spray drift risk assessments for registering and re-registering pesticides using current worst case scenario assumptions currently used in risk assessments

Ensuring safety cont’d Efficacy studies will need to be conducted to ensure droplet size classifications (DSC) used by UAS will be effective EPA will need to establish AEZ size and compliance methods Pesticide risk assessments will need to account for worker exposure from additional fills, increased concentration of finished mix and additional workers present at time of application (Pilot and observers) Additional human and ecological risk assessments will need to be performed to determine impact of Non-Point mixing and loading sites

Ensuring safety cont’d American National Standards Institute (ANSI) echoes these concerns in a recent UAS standards document. They cited the need for standards in pesticide application using UAS with emphasis on: Communication Treatment Efficacy Operational Safety Environmental Protection Equipment Reliability Airspace integration

Are exemptions needed? Possibly Used as replacement of backpack and other hand operated application tools Acreage completely inaccessible to manned aircraft provided treatment area is small Small total treated acres by individual UAS or “Swarms”

Summary UAS pesticide applications are aerial applications Current aerial label language applies and is likely not being complied with Current WPS rules apply and requires more in depth assessment due to more people on site Further research and testing will likely result in UAS specific label language An exemption process should be looked at for extremely small treatment areas