1. 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

2. 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.

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

4. 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.

6. What we know
“A User’s Guide for AgDRIFT : 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

7. 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.

8. 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

9. 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

10. 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

11. 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

12. 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

13. 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”

14. 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