Pesticide Use Survey Report For 

Agricultural Aviation 

A Study Conducted by the 

National Agricultural Aviation Association 

May 2004 

National Agricultural Aviation Association 

1005 E Street, SE 

Washington, DC 20003 

(202) 546-5722 

information@agaviation.org

www.agaviation.org
ii

Table of Contents

Section Page Number

Introduction 

Background . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1 

Objectives . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1 

Methodology . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1 

Report Format . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2 

Executive Summary . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3 

Detailed Findings

Part 1—Location 

Question 1: In which State is your aerial application business located? . . . . . . . . . . . . . . . . . . . 5 

Question 2: Please list the states in which you perform aerial applications. . . . . . . . . . . . . . . . . . 6 

Part 2—Equipment 

Question 3: How many operating aircraft are used in your aerial application business? . . . . . . . . . . 7 

How many planes? . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7 

 How many of these planes have a closed cockpit? . . . . . . . . . . . . . . . . . . . . . . . . . 8 

 How many helicopters? . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7 

 How many of these helicopters have a closed cockpit? . . . . . . . . . . . . . . . . . . . . . . . 8 

Question 4 (a): Are your aircraft equipped with smokers to determine wind direction while 

 performing aerial applications? . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9 

Question 4 (b): If you do use a smoker, how often do you engage it? . . . . . . . . . . . . . . . . . . . . .10 

Part 3—Mixing/Loading Operations 

Question 5: What percent of all spray jobs does the pilot of the aircraft also mix & load pesticides? . . . . 11 

Question 6: If the mixer/loader and the pilot are different individuals, on average how many 

 different aircraft are usually supported by that mixer/loader on an average day? . . . . . . . . . . . . . . 12 

Question 7: When PPE is required, do you use disposable or reusable equipment? . . . . . . . . . . . . . 13 

Question 8: Does the operation utilize a closed mixing/loading system (mechanical pesticide transfer)? . . 14 

Question 9: Question related to mixing loading practices. . . . . . . . . . . . . . . . . . . . . . . . . . . 15 

Question 10: Question pertaining to number of pesticides handled per day by a mixer/loader. . . . . . . . 17 

Question 11: Question pertaining to number of days a particular type of pesticide would be applied? . . . 18 

Part 4—Application Practices 

Question 12: Which of the following do you use to minimize spray drift? . . . . . . . . . . . . . . . . 20 

Question 13: When applying pesticides, what percent of applications use specific type of swath marking? . 22 

Part 5 – Daily Acres Treated 

Question 14: Average acres and maximum acreage treated per day according to crop. . . . . . . . . . . . 23 

Appendix

Survey & Cover Letter . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1 - 3 

Raw survey data can be made available on request from the NAAA. 
1

Introduction

Background 

The National Agricultural Aviation Association (NAAA) conducted this study to better 

understand how aerial pesticide applications are made in the United States today. Specific 

objectives are outlined below. Similar studies were conducted by NAAA in 1992, 1994, 1998 

and 2000. Some questions were new and some questions asked in earlier studies were not 

repeated here. Copies of earlier survey results are available by calling the NAAA. 

Objectives 

One of the primary objectives of this study was to obtain actual data depicting pesticide use 

patterns in the aerial application industry to supply to the Environmental Protection Agency 

(EPA). NAAA worked in conjunction with the EPA in developing questions in this study. The 

EPA, as part of its pesticide (re) registration process, must determine occupational exposure risks 

associated with the aerial application of pesticides. NAAA is concerned that the exposure data 

that EPA uses to make occupational risk assessments pertaining to aerial applicators are 

theoretical and/or overly estimate exposure risk. For this reason, the Association undertook 

collecting actual, up-to-date, data reflective of current industry practices. This study provides 

that information. 

A second objective of the study was to identify drift mitigation techniques used by the aerial 

application industry and quantify their usage to indicate to the EPA the advanced technologies 

and methods commonly practiced to make on-target applications and protect the environment. 

This information can be used to support aerial use on pesticide labels. 

Another objective of the study was to develop information to better define the agricultural 

aviation industry in the United States by better identifying the scope of work conducted; and 

equipment, products and application techniques used. 

Methodology 

NAAA sent out 1,899 pesticide use surveys in March of 2003 to FAA Part 137 Aerial 

Application Operators throughout the United States. The mailing list was developed by the 

NAAA using a list of all FAA Part 137 operators and checking that list with the executive 

directors of individual state and regional agricultural aviation associations throughout the 

country to determine which of those operators were still in business. The mailed surveys sent 

out included a message from the NAAA president with a return envelope. The survey form and 

the cover letter are in the appendix. 

NAAA received 595 surveys. The U.S. Postal Service returned twelve (12) surveys to the 

NAAA because the addresses were no longer valid. Twelve (12) sent the surveys back with a 

note that they were no longer in business. Some operators had answered only some of the 

questions. In these cases the information provided was used. Three (3) completed surveys were 

received from Canadian operators and while we appreciate their input, the responses were not 

used in tabulating the results. The return rate for the survey was 31.5%.1

 In 1998 NAAA 

conducted an industry survey of the aerial application industry with a similar target list and the 

response rate was 31%. 

The returned questionnaires were tabulated on a Microsoft Excel Spreadsheet listing all of the 

information supplied by the respondents. The data was checked for missing information and 

 

1

 595/(1,899-12 returned by the Post Office) = 31.5% 
2

obvious errors in completion of the survey form. A committee of aerial applicators arrived at a 

set of reasonable standards to judge the accuracy of the data submitted. Those standards are 

included in the narrative analyzing each specific question in the Detailed Findings portion of this 

report. References to individual responses that were questioned by the panel can also be found 

in the Detailed Findings portion of this report and in the actual survey data. 

NAAA has the data generated by this survey in both paper and electronic format. Individuals 

interested in the data may request it by contacting the NAAA office at (202) 546-5722. 

Report Format 

The Executive Summary outlines the study makeup and objectives along with providing an 

overview of the survey findings. The Detailed Findings portion has been divided into 5 parts: 

Part 1- Location, Part 2 – Equipment, Part 3 – Mixing and Loading, Part 4 – Application 

Practices, and Part 5 – Daily Acres Treated. 
3

Executive Summary 

The mail survey was sent in March of 2003 to 1,899 FAA Part 137 Aerial Application Operators 

throughout the United States. The NAAA received 595 surveys in response. 

The study results are divided into 5 parts: Part 1- Location, Part 2 – Equipment, Part 3 – Mixing 

and Loading, Part 4 – Application Practices, and Part 5 – Daily Acres Treated. 

Location

NAAA’s records show that aerial application operations are located in 47 out of 50 states. 

Vermont, Hawaii and Rhode Island are the states that do not have an aerial application operation. 

Responses to this survey were received from application businesses located in 41 of 50 states. 

This survey is primarily designed to provide the EPA with information to better define the 

agricultural aviation industry in the United States by identifying the scope of work conducted; 

and equipment, products and application techniques used. 

The largest number of responses to the survey were received from Arkansas (first - 59), Texas 

(second - 52), Louisiana (third - 40), and Kansas and California (tied for fourth - 31). 

A total of 93 operators reported that they worked in 3 states or more. Of this total, 46 operated in 

only three states, 21 in four states, and the number gradually decreased until only 5 operators 

reported working in more than eight states. 

Equipment

Based on information collected from the respondents there are an average of 2.2 aircraft per 

aerial application business. 88% of the aircraft used in the industry are fixed wing aircraft and 

the other 12% are rotorcraft, or helicopters. 98% of fixed-wing aircraft have a closed cockpit; 

90% of the helicopters have closed cockpits. An average of 97% of the combined total of all 

agricultural aircraft are equipped with closed cockpits. 

Approximately 85% of the aircraft operated by these applicators are equipped with smokers to 

determine wind direction at an application site. Nearly 80% of the applicators that use a smoker 

do so before applying product next to a sensitive area. 35% of the applicators that use a smoker 

do so at least once every load. 25% of the respondents that use a smoker do so every 2-4 swaths 

(a swath is a pass across the field in one direction) and another 25% do so every 5-7 swaths. 9% 

use their smoker during every swath. 

 

Mixing/Loading Operations

From the responses received, 29% of all spray jobs are mixed and loaded by the pilot applying 

the load. The other 71% percent are mixed and loaded by a separate mixer/loader. In addition, 

the average number of aircraft a mixer/loader, who is not the pilot, services, is 1.48 

When personal protection equipment (PPE) is required for mixing a pesticide, 14% use 

disposable PPE; 17% use reusable PPE and 69% use both types of PPE. 

More than three-quarters (76%) of those aerial application operators surveyed indicated that they 

use a closed mixing/loading system when preparing crop protection products for application. 

Just over 24% did not use a closed system. Closed mixing/loading systems, as described in the 

question, are those systems that contain some sort of mechanical pesticide transfer function that 

removes one, if not all the steps, involved in mixing and loading a pesticide that may cause 

exposure to a worker. 
4

When pesticides are mixed and loaded, 38% of the respondents use product from open pour 

containers; 36% use product containers with dry break openings; 23% without dry break 

openings and 3% use other types of containers or methods. 

A typical mixer-loader will handle 4.3 different pesticides per day. Results of the survey also 

indicated that herbicides are applied on average 71 days out of the year; insecticides are applied 

69 days out of the year and fungicides are applied 40 days out of the year. 

Application Practices

The survey asked what types of techniques/tools applicators use to minimize drift. 86% of the 

respondents indicated that they use drift control additives; 85% of the respondents indicate that 

they use special nozzles; 82% of the respondents indicated that they use changes in the flight 

pattern to mitigate drift; 72% use wind detectors, such as smokers; 59% use changes in nozzle 

pressure; and 28% use diluting formulations (i.e., increasing the spray volume of water and/or 

carrier per acre). 

The survey also included a question asking operators what type of method they used for swath 

guidance. 92% use GPS; 28% use automatic flaggers; and 4% use human flaggers. Some 

operators use more that one method simultaneously. 

Daily Acres Treated

The top three crops with the largest average number of acres treated per day are cotton (1,080 

acres), rice (725 acres), and small grains (597 acres). Operators indicated that they treat small 

grains, such as wheat and barley more than any other crop; corn/sorghum and soybeans were tied 

for second and alfalfa and cotton were tied for fourth. 

In terms of the three crops with the largest maximum number of acres treated per day, cotton 

(2,145 acres) again topped the list followed by forests (1,481 acres) with rice (1,344 acres) in 

third place. 
5

DETAILED FINDINGS 

PART 1 - LOCATION 

Question 1.

In which State is your aerial application business located? 

State Responses Percentage State Responses Percentage State Responses Percentage 

AK 0 0.0% LA 40 7.0% OH 3 0.5% 

AL 6 1.0% MA 0 0.0% OK 16 2.8% 

AR 59 10.3% MD 0 0.0% OR 10 1.7% 

AZ 6 1.0% ME 2 0.3% PA 6 1.0% 

CA 31 5.4% MI 4 0.7% RI 0 0.0% 

CO 25 4.4% MN 30 5.2% SC 4 0.7% 

CT 0 0.0% MO 11 1.9% SD 12 2.1% 

DE 2 0.3% MS 24 4.2% TN 4 0.7% 

FL 11 1.9% MT 25 4.4% TX 52 9.1% 

GA 12 2.1% NC 9 1.6% UT 2 0.3% 

HI 0 0.0% ND 30 5.2% VA 4 0.7% 

IA 11 1.9% NE 28 4.9% VT 0 0.0% 

ID 11 1.9% NH 1 0.2% WA 24 4.2% 

IL 10 1.7% NJ 1 0.2% WI 5 0.9% 

IN 3 0.5% NM 2 0.3% WV 1 0.2% 

KS 31 5.4% NV 0 0.0% WY 1 0.2% 

KY 0 0.0% NY 3 0.5% 

The first column, entitled “State,” lists all the states in which surveys were sent to aerial 

application operators including those that had no reported operators. The second column, 

entitled “Responses,” lists the number of responses received from aerial application operators 

that indicated their operation was located in that state. The total of responses to this question 

was 572. The third column, entitled “Percentage,” calculates the number of responding aerial 

application operations in that state, as a percentage of the 572 responses received to this 

question. 

Responses were received from application businesses located in 41 of 50 states. NAAA records 

indicate aerial application businesses located in 47 of the 50 states. These surveys were sent to 

all applicators shown in NAAA records in these states. Vermont, Hawaii, and Rhode Island, 

according to NAAA records, have no aerial application operations based there. 

As indicated by the table above, the most responses to the survey were received from Arkansas 

(first - 59), Texas (second - 52), Louisiana (third - 40), and Kansas and California (tied for fourth 

- 31). 
6

Question 2.

Please list the states in which you perform aerial applications. 

State Responses Percentage State Responses Percentage State Responses Percentage 

AK 1 0.1% LA 48 4.7% OH 10 1.0% 

AL 15 1.5% MA 1 0.1% OK 35 3.4% 

AR 76 7.4% MD 9 0.9% OR 16 1.6% 

AZ 9 0.9% ME 3 0.3% PA 9 0.9% 

CA 35 3.4% MI 11 1.1% RI 0 0.0% 

CO 39 3.8% MN 44 4.3% SC 11 1.1% 

CT 1 0.1% MO 31 3.0% SD 26 2.5% 

DE 5 0.5% MS 32 3.1% TN 17 1.7% 

FL 15 1.5% MT 29 2.8% TX 83 8.1% 

GA 22 2.1% NC 20 2.0% UT 6 0.6% 

HI 0 0.0% ND 56 5.5% VA 18 1.8% 

IA 27 2.6% NE 45 4.4% VT 4 0.4% 

ID 29 2.8% NH 1 0.1% WA 32 3.1% 

IL 21 2.0% NJ 5 0.5% WI 11 1.1% 

IN 9 0.9% NM 15 1.5% WV 9 0.9% 

KS 56 5.5% NV 4 0.4% WY 9 0.9% 

KY 6 0.6% NY 9 0.9% 

The first column, entitled “State,” lists all the states in which surveys were sent to aerial 

application operators including those that had no reported operators. The second column, 

entitled “Responses” lists the number of responses received from operators that indicated they 

performed aerial applications in that state. The third column, entitled “Percentage,” calculates 

the percentage of aerial application operators responding that perform aerial applications in that 

state compared to the total responses. 

All respondents indicated the states in which they worked but four (4) respondents failed to 

indicate the state in which the operation is located. 

A total of 93 operators reported that they worked in 3 states or more. Of this total, 46 operated in 

only three states, 21 in four states, and the number gradually reduced until only 5 operators 

reported working in more than eight states. These 5 operators reported working in 10, 12, 14, 16 

and 18 states, respectively.
7

PART 2 - EQUIPMENT 

Question 3.

How many operating aircraft are used in your aerial application business? ________ 

 How many planes? ________ How many of these planes have a closed cockpit?________ 

 How many helicopters? ________ How many of these helicopters have a closed cockpit?________ 

This is a five-part question. The first part of the question was to determine the average number 

of aircraft used in an aerial application business. 

How many operating aircraft are used in your aerial application business? 

 

Responses were received from 572 operators indicating that they used 1,262 aircraft in their 

aerial application business. This is an average of 2.2 aircraft per operation. 

This question asks for the number of operating aircraft that are used. The responses received 

indicate that six operators listed fewer aircraft in the first part of the question than the number of 

aircraft listed after adding together the number of airplanes and helicopters they had in their 

business. The reason for this is some of aircraft were in operation and some were not. The 

breakdown totals were adjusted to remove the non-operating aircraft. Changes were made to one 

operator’s response (response # 47) who had miscalculated the total and a second (response # 

573) was dropped from the total data because the breakdown was not shown. 

How many planes? _______ How many helicopters? _______ 

TYPE OF AIRCRAFT USED

Airplanes

88%

Helicopters

12%

Respondents to the second part of the question provided data indicating that they use 1,108 

airplanes and the fourth part of the questions indicates that respondents use 154 helicopters. 

Based on these figures, fixed wing aircraft account for 88% of the fleet and helicopters make up 

the remaining 12%. 

Other findings from the data show that of the 572 respondents, 19 employ both airplanes and 

helicopters. The remaining operators use only one type of aircraft - 516 use airplanes and 37 use 

helicopters exclusively. 
8

How many of these planes have a closed cockpit?

The third part of this question indicates that 1,083 of the 1,108 fixed-wing aircraft have a closed 

cockpit. This amounts to an average of 98% of the agricultural airplanes having a closed cockpit. 

How many of these helicopters have a closed cockpit? 

The fifth part of this question indicates that 138 of the reported 154 rotorcraft, or helicopters 

have closed cockpits. This amounts to an average of 90% of the helicopters having a closed 

cockpit. 

COMBINED AIRPLANE & HELICOPTER COCKPIT 

DESIGN OF SURVEYED AIRCRAFT

Closed Cockpits

97%

Open Cockpits

3%

Other data that can be gleaned from the responses to this multi-part question indicate that 97%, 

or 1,221 of the 1,262 combined agricultural aircraft covered by this survey are equipped with 

closed cockpits. 
9

Question 4 (a).

Are your aircraft equipped with smokers to determine wind direction while performing aerial applications? 

(Please check one of the following) Yes No 

SMOKER EQUIPPED AIRCRAFT

Smoker Equipped

85%

No Smoker

15%

 Total Total Percentage Total Percentage 

 Aircraft Airplanes Airplanes Helicopters Helicopters 

Smoker Equipped 1066 1034 94% 32 21% 

Not Equipped 189 68 6% 121 79% 

Total Surveyed 1255 1102 153 

A total of 572 operators responded to this question – 509 said that their aircraft are equipped 

with a smoker while 63 did not have their aircraft so equipped. The graph and data indicate that 

85% percent of the aircraft are equipped with smokers. The survey data show that 1,066 of the 

reported 1,255 aircraft are so equipped.

The purpose of this question was to determine what percentage of applicators use smokers to 

inform them of wind direction and atmospheric conditions at the time and place of application 

and how they use this technology. A smoker injects a small amount of oil into the aircraft engine 

exhaust creating smoke that is released into the air. This smoke aids the applicator in determining 

wind direction and velocity in order to make the necessary application adjustments to ensure that 

the chemical application is to the target area. One (1) responder specifically stated that he did not 

have smoke equipment on the aircraft but he sends a person to the field to light a fire on the 

ground to determine air movement. 

Another use of the smoker is to help mark the location of the spray run in order to ascertain the 

location of the next swath2

. This method is sometimes used in conjunction with the automatic 

flagger. With the advent of the GPS for swath marking, the auto-flagger and smoker are not 

depended on as much as they were in the past. 

 

2

 A swath is a spray pass across the field in one direction. 
10

Question 4 (b).

If you do use a smoker, how often do you engage it? (Please check all that apply) 

 Before an application next to a sensitive area Every swath run Every 2-4 swath runs 

 Every 5-7 swath runs Every load 

Other (please explain) __________________ 

22%

9%

25%

25%

35%

80%

0% 20% 40% 60% 80% 100%

Near a sensitive area

Every load

Every 2-4 swaths

Every 5-7 swaths

Every swath

Other

FREQUENCY OF SMOKER USE

Of the total 509 responders that have aircraft equipped with smokers, 407 or 80% indicated that 

they use the equipment before applying product next to a sensitive area. 177 or 35% of the 

applicators said that they use a smoker at least every load. The same amount of respondents, 126 

or 25% indicated that they use the smoker every 2-4 or every 5-7 swath runs. 44 or 9% of the 

respondents said that they use the smoker on every swath run. Another 113 or 22% of the 

applicators that use a smoker selected “other”. In the remarks, 100 of those 113 described 

“other” as using a smoker “as required” or “as needed”. 

The second part of the question was designed to allow respondents to check any combination of 

smoker use frequency that applied to them and many did, as is indicated. Therefore, the 

responses need not total 100%.
11

PART 3—MIXING/LOADING OPERATIONS 

Question 5.

What percent of all spray jobs does the pilot of the aircraft also mix and load pesticides? 

LOADS MIXED BY PILOT

Pilot mixed

29%

Mixer/loader mixed

71%

Percentage of Loads Mixed/Loaded 

by the Pilot Performing the Application 

0% 181 51-60% 8 

1-10% 164 61-70% 4 

11-20% 21 71-80% 21 

21-30% 25 81-90% 17 

31-40% 2 91-100% 83 

41-50% 43 Responses 569 

Respondents were asked to estimate the percentage of the loads in which an individual mixed 

and loaded the chemical and then served as pilot of the aircraft. A total of 569 operators 

responded to this question. The responses varied from 0% to 100% with an average of 29%. The 

table above shows the number of responses registered in each percentage range as estimated by 

the operators. 

Some aerial application operations are operated by a single person. The owner does the 

mixing/loading, piloting of the aircraft and the bookkeeping. In other operations, the pilot is 

only the pilot and all loads are mixed and loaded by a separate individual. However, in actual 

practice, the pilot occasionally mixes his own load if the mixer/loader is not at the facility or is 

busy with another task. 
12

Question 6.

If the mixer/loader and the pilot are different individuals, on average how many different aircraft are usually 

supported by that mixer/loader on an average day? 

Number of Aircraft Serviced 

by a Single Mixer/Loader 

0.5 3 3.0 12 

1.0 280 3.5 1 

1.1 1 4.0 4 

1.5 13 5.0 1 

2.0 159 10.0 2 

2.5 2 Responses 478 

We had 478 responses that met the criteria explained below. The results indicate that each 

mixer/loader supports between .5 and 10 aircraft per person. From the data received, 1.48 is the 

average number of aircraft that a mixer/loader services. The above table illustrates the 

breakdown of responses received for this question. 

This question on the average number of aircraft loaded by a mixer-loader assumes that the pilot 

of the aircraft is not the mixer/loader. Therefore, any responses of 100% to Question # 5 should 

not have a response to Question #6. Any response listing 100% for Question #5 was removed 

from the data used to calculate the responses to Question #6. 

 

Our review panel removed three (3) survey responses that did not follow this criterion (responses 

242, 334, and 482). Our panel concluded that these figures were entered in error because the 

respondent did not understand the question. 
13

Question 7.

When Personal Protection Equipment (PPE) is required, do you use disposable or reusable equipment? 

(Please circle one) Disposable Reusable Both 

TYPE OF PERSONAL PROTECTIVE EQUIPMENT 

(PPE) USED

Disposable

14%

Reusable

17%

Both

69%

Total Disposable Reusable Both 

Responses Number Percentage Number Percentage Number Percentage 

572 78 14% 97 17% 397 69% 

A total of 572 operators responded to this question that asked if they preferred to utilize 

disposable or reusable Personal Protective Equipment (PPE) when required for mixing/loading 

crop protection products. The most common response was “Both” which 397 respondents chose, 

or 69%. 97 respondents chose “Reusable” or 17%, and 78 respondents chose “Disposable” or 

14% of the total. 
14

Question 8.

Does the operation utilize a closed mixing/loading system (mechanical pesticide transfer)? 

Please circle one of the following: Yes No 

CLOSED LOADING SYSTEMS

Closed

76%

Non-closed

24%

The NAAA received 561 responses of which 427 or 76% said that they utilize a mixing system 

to lessen worker exposure while mixing. 134 responders or 24% do not utilize a closed 

mixing/loading system. 

More than three-quarters (76%) of those aerial application operators surveyed indicated that they 

use a closed mixing/loading system to prepare crop protection products for application. Closed 

mixing/loading systems, as described in the question, are those systems that contain some sort of 

mechanical pesticide transfer that removes one, if not all, of the steps involved in mixing and 

loading a pesticide that may cause exposure to a worker. 

 
15

Question 9.

When pesticides are mixed and loaded, what percentage of the total mixing/loading jobs use the following 

practices? Please estimate a percentage at the end of each of the following bullets (Total should equal 100%): 

Percentage of mixing/loading jobs spent opening product containers and pouring the pesticide 

formulations into the mixing/loading tank (also known as open pour) ________% 

Percentage of mixing/loading jobs spent transferring pesticides to the mix tank from product 

containers with dry break openings? ________% 

Percentage of mixing/loading jobs spent transferring pesticides to the mix tank from product 

containers without dry break openings? ________% 

Other ________% Please explain ________________________________________________________ 

MIXING/LOADING METHOD USED

Containers with 

dry break

36%

Open pour

38%

Other

3%

Containers 

without dry 

break

23%

479 responses were recorded for this question to calculate the percentages. The question requires 

respondents to assign percentages to mixing loading practices used at their operation and the 

cumulated total must equal 100% 

Open pour is assumed to mean that the contents of the chemical product container are physically 

poured into the mix tank or aircraft dispersal tank. This method is reportedly used at least part of 

the time by 458 respondents for an average of 38% of the pesticide mixing. 

Containers with dry break openings are designed to allow coupling and uncoupling a hose to the 

fitting on the container without spilling any of the contents. This is usually accomplished by the 

use of a check valve. 369 respondents reported using this type of container in an average of 36% 

of the loading situations. 

Product containers without dry break openings are not equipped with an automatically activated 

leak prevention device, such as a check valve. This type of container was used at least part of the 

time by 352 responders. They reported using this type of loading in an average of 24% of loading 

operations. 

There were 83 responses rejected because the percentages submitted did not equal 100%. Twenty 

six (26) of these indicated by either a notation or by the answer that they considered “open pour” 

and “without dry break” to be referring to the same type container since an open pour container 

probably does not have a dry break. Six (6) additional responses were eliminated because in their 

explanation for “other”, they broke down the percentage of loader duty time to include “waiting 

for airplane” and “fueling airplane”. 
16

Additional explanations such as “mix in hopper,” “don’t disconnect,” “all loaded through closed 

system” and “pump directly to hopper” were accepted if the percentage break down totaled 

100%. The question was asked to determine the method a liquid material was handled in the 

mixing loading process. A total of nine (9) responders stated that liquids were mixed/loaded 

using water-soluble bags or dry materials. Seven (7) of these responses were accepted in the 

percentage calculation. Two (2) of these were rejected because they responded in the manner 

listed above detailing why responses were rejected. 

We believe that it is important to note some of the respondents added comments to this question 

that manufacturers should standardize the openings of product containers so one system could 

handle all, or at a minimum, many of the crop protection products. 
17

Question 10.

On average, how many pesticides are typically handled per day by a mixer-loader at your aerial application 

operation? Please provide an actual number in the following space: ________ 

Data results for Question 10 

Chemicals Number of Chemicals Number of Chemicals Number of 

Handled Responders Handled Responders Handled Responders 

0 3 5 76 15 6 

1 21 5.5 1 16 1 

1.5 5 6 25 17.5 2 

2 86 6.5 1 20 13 

2.5 12 7 12 21 1 

3 100 7.5 3 25 4 

3.3 1 8 20 40 2 

3.5 8 9 5 50 1 

4 57 10 39 55 1 

4.5 1 12 5 100 1 

Based on 473 responses using an allowable maximum of 10 pesticides handled per day to 

perform the calculation (see explanation below), the daily average of pesticides handled per day 

by a mixer-loader is 4.3 pesticides. Additional calculations based on 500 responses using an 

allowable maximum of 20 different pesticides handled per day to perform the calculation, the 

daily average of pesticides handled per day by a mixer-loader is 5.0. 

Those responses that were not included in the calculations were those that included information 

on the number of gallons of pesticide handled or percentage of pesticides handled, rather than 

what was asked for—the number of pesticides handled per day. Three (3) individual responses 

that showed zero (0) as the number of pesticides handled daily were also not considered. 

Due to questionable responses submitted by a few respondents regarding this question, our 

survey review panel felt it necessary to determine a realistic data range of reported responses to 

this question. The panel determined that a reasonable limit for the maximum number of 

pesticides handled per day was 20. This resulted is discarding from the calculation the following 

responses: one response listing 21, one responses listing 25, two responses listing 40, one 

response listing 50, one response listing 55 and one response listing 100 pesticides handled on a 

typical day by a mixer-loader. 

We also calculated the average number of pesticides handled per day by a mixer-loader using 10 

as the maximum allowable number of pesticides handled per day to perform the calculation. 

Using this range, 473 responses were accepted into the calculation resulting in an average of 4.3

pesticides being handled per day by a mixer-loader. The panel believes that 10 is a more 

reasonable maximum number of pesticides handled on a typical day. 
18

Question 11.

In a given year, what is the maximum number of days that a particular type of pesticide would be applied? 

Please provide a number in the space following each classification of pesticide. 

Insecticide: ________ Herbicide: ________ Fungicide: ________ 

40

69

71

0 10 20 30 40 50 60 70 80

Number of Days Applied

Herbicides

Insecticides

Fungicides

DAYS OF APPLICATION BY PESTICIDE TYPE

Number of Days Applied by Pesticide Type 

 Insecticide Herbicide Fungicide 

0-29 132 88 197 

30-59 129 150 138 

60-89 99 114 61 

90-119 63 69 30 

120-149 45 38 7 

150-179 25 24 7 

180-209 19 27 6 

210-239 5 5 2 

240-269 9 6 0 

270-300 4 2 1 

 530 523 449 

As indicated in the bar chart above, herbicides are applied more often, on a daily basis, than any 

other type of crop protection product. Insecticides run a close second. Respondents indicate that 

herbicides are applied, on average, 71 days out of the year. Insecticides are applied, on average, 

69 days out of the year, and fungicides are applied, on average, 40 days out of the year. These 

averages were obtained from the data supplied by 543 responders. 

It was also interesting to note that although herbicides were applied on average, more days out of 

the year, insecticides were applied by a slightly greater percent of operators responding. 

Calculations show that based on 543 responses, 98% applied insecticides, 96% applied 

herbicides and 83% applied fungicides. 

Some responders stated that they applied a certain pesticide type 365 days out of the year. The 

survey review panel determined that this is completely unrealistic and that the respondents 

misinterpreted the question to read “the number of days that a certain type of chemical is on 

hand,” similar to what is asked on a Tier II report. The panel determined that a realistic range of 
19

days a pesticide was used a year was between 10 days to 300 days out of the year. Any response 

outside of this range was not considered. As a result, thirteen (13) responses were not considered 

because the combined total of days of application was less than 10 days. Three (3) responses 

were eliminated because they indicated that they applied a certain type of pesticide more than 

300 days per year. Responses # 14, 17, 472 and 485 were eliminated because the responses were 

labeled as a percent (%) instead of number of days. 
20

PART 4—APPLICATION PRACTICES 

Question 12.

Which of the following do you use to minimize spray drift? (Please check all that apply) 

Drift Control Additives Wind detectors Changes in pressure 

Special nozzles Changes in flight patterns Diluting formulations 

28%

59%

72%

82%

85%

86%

0% 20% 40% 60% 80% 100%

Percentage of Operators Using Each Method

Drift control additive

Special nozzles

Changes in flight pattern

Wind Detectors

Changes in pressure

Diluting formulations

METHODS USED FOR DRIFT REDUCTION

569 responses were accepted to calculate percentages for this question. As shown in the question 

stated above the graph, the percentages need not total 100%. 

Drift control additives are products that can be mixed with the chemical to eliminate the breakup of droplets into fine particles resulting in decreased drift. This type of drift minimization 

practice was used by 86% of our responders and was the leading method used. 

Special nozzles can be selected to produce a droplet size that is larger and more uniform in size 

and less susceptible to drifting. Selecting special nozzles for drift control was a close second with 

85% choosing this as a drift reduction method. 

Changes in flight patterns was footnoted in the survey to mean leaving buffer zones on the 

downwind side of a field during the time of the initial application and returning to complete that 

portion of the field once the wind has shifted. This procedure, with an 82% response rate was in 

third place. 

Wind detectors range from utilizing combustible materials at the application site or smokers 

installed on the aircraft to generate smoke in order to determine wind direction, to using 

anemometers to obtain this information. 72% of the responders reported that they use some sort 

of wind detector as a form of reducing movement of the chemical away from the target area. 

Changes in nozzle pressure will alter the droplet size, thereby it can be used to mitigate the 

creation of fine particles that are more prone to drifting. 59% of the responders reported that they 

use changes in nozzle pressure to reduce drift. 

Diluting formulations means increasing the total volume of liquid per acre so that there is a 

smaller amount of active ingredient in each droplet that is applied. This method was selected by 

28% of the responders. 
21

The survey review panel was unable to fully explain the reason that 89%3

 of the operators have 

smoke generating equipment installed on their aircraft but only 72% said that they used wind 

detectors for controlling drift. One possible explanation is that some operators responding to the 

survey considered smoker use as a tool for identifying wind direction and velocity, yet they do 

not put this into the context of mitigating drift. 

 

3

 89% of operators responded that they had smoke generating equipment installed. When analyzed as a percentage 

of the aircraft covered in the report, 85% are equipped with smokers. 
22

Question 13.

When applying pesticides by air, what percent of your applications use: 

 Human flaggers ________% Automatic flaggers ________% GPS ________% Other ________% 

4%

4%

28%

92%

0% 20% 40% 60% 80% 100%

Percent of Operators Using Each Method

GPS

Automatic Flaggers

Human Flaggers

Other

METHOD USED FOR SWATH GUIDANCE

568 responses to this question were used for completion of the data. This question was 

constructed with the understanding that more than one type of guidance can be used 

simultaneously; as a result the percentages need not total 100%. 

The above table shows that approximately 92% of the information for swath guidance is being 

provided by GPS4

 equipment installed in the aircraft. An NAAA 1998 survey indicated that 60% 

of agricultural airplanes were equipped with GPS as compared to 25% in 1994. 

The use of GPS and the Automatic Flagman5

 has virtually eliminated the need for and use of 

human flaggers in the aerial application industry and thereby has reduced occupational exposure 

from the aerial use of pesticides. Slightly less than 4% of those responding to the survey said that 

they used human flaggers compared to 15% in 1998 and 38% in 1994. 

The increased use of GPS equipment has also resulted in a decrease in the use of the automatic 

flaggers from 73% in 1994 to 58% in 1998, to its lowest level of 28% in 2003. 

The survey panel decided to not consider two responses. Response # 236 was not included 

because the respondent, after answering that 90% of his/her applications use “human flaggers” 

remarked that the human flaggers are to check wind and temperature at the application site and 

therefore shouldn’t be considered as an exposure risk. Response # 503 was determined to be 

incomplete. 

 

4

 Global Position Satellite system. GPS uses satellite technology enabling the ag pilot to make a swath run directly 

next to the previous one. The accuracy of the GPS unit provides the opportunity for exceptional positioning control. 

5

 Automatic Flagman, also known as automatic or auto flaggers, dispense a biodegradable tissue at the end of a 

swath run to enable the ag pilot to estimate the position of the next swath to be made. 
23

PART 5 – DAILY ACRES TREATED 

Question 14.

Please complete the following table. For each crop, please indicate the usual and the maximum number of 

acres that you treat on average during a single day, with a single aircraft using a single pesticide.6

Usual Number of Acres Treated Per 

Day, Using a Single Aircraft Using a 

Single Pesticide 

Maximum Number of Acres Treated 

Per Day, Using a Single Aircraft 

Using a Single Pesticide 

Alfalfa 

Corn, Sorghum 

Cotton 

Forests 

Orchards (Fruit and Nut Trees) 

Pastures and Rangeland 

Rice 

Small grains (Wheat, Barley) 

Soybeans 

Leafy vegetables 

Roots and tubers 

Small fruits (Grapes and Berries) 

Other: _____________________ 

 Usual Acres Treated per Day Maximum Acres Treated per Day

Crop Treated Number of Percent of Usual Number of Percent of Maximum 

(567 Operators responded) Responses Responders Acres Responses Responders Acres 

Alfalfa 194 34% 322 197 35% 785 

Corn, Sorgum 249 44% 541 248 44% 1281 

Cotton 191 34% 1080 180 32% 2145 

Forests 43 8% 587 43 8% 1481 

Orchards (Fruit & Nut Trees) 54 10% 277 53 9% 598 

Pastures & Rangeland 177 31% 549 173 31% 1238 

Rice 139 25% 725 136 24% 1344 

Small grains (Wheat, Barley) 348 61% 597 341 60% 1307 

Soybeans 249 44% 591 237 42% 1282 

Leafy vegetables 75 13% 389 72 13% 811 

Roots & Tubers 102 18% 593 98 17% 1191 

Small fruits (Grapes, Berries) 27 5% 339 24 4% 514 

Other 42 7% 483 42 7% 1324 

The top three crops with the largest average number of acres treated per day, as indicated from 

the table above are cotton (1,080 acres), rice (725 acres), and small grains (597 acres). More 

operators indicated that they treat small grains, such as wheat and barley, more than any other 

crop; corn/sorghum and soybeans were tied for second and alfalfa and cotton were tied for 

fourth. 

In terms of the top three crops with the largest maximum number of acres treated per day, cotton 

(2,145 acres) again topped the list with forests (1,481 acres) and rice (1,344 acres). 

A breakdown of “Other Crops” treated by survey respondents is on the following page. 

 

6

 NAAA realizes that when making applications to some crops, more than one pesticide will be used. Yet, for 

purposes of documenting exposure data as outlined by the EPA, we need you to answer these questions as if you use 

a single pesticide in each application load. 
24

Break down of Number of Percent of Usual Number of Percent of Maximum 

"Other" Crops Responses Responders Acres Responses Responders Acres 

Aquatic 1 0.2% 100 1 0.2% 200 

Christmas trees 2 0.4% 165 2 0.4% 375 

CRP (Gov't non-crop land) 1 0.2% 350 1 0.2% 1500 

Fallow (Idle - out of production) 3 0.5% 220 3 0.5% 1500 

Gladiolas 1 0.2% 50 1 0.2% 250 

Misc. minor crops 1 0.2% 100 1 0.2% 300 

Mosquito 2 0.4% 1624 2 0.4% 2724 

Peppermint 1 0.2% 600 1 0.2% 900 

Public Health 2 0.4% 1375 2 0.4% 3225 

Pulp 1 0.2% 400 1 0.2% 2400 

Right-of-way (powerlines, etc.) 3 0.5% 100 3 0.5% 300 

Sugar cane 6 1.1% 633 6 1.1% 1700 

Sod 2 0.4% 250 2 0.4% 1300 

Sunflower 13 2.3% 476 14 2.5% 1229 

Tobacco 2 0.4% 213 2 0.4% 413 

Not surprisingly, the largest average number of acres treated per day by responding applicators 

that treat “other crops” were for mosquito/public health spraying. This is typically low-volume 

application work. It should also be noted that only four individuals responded that they perform 

mosquito/public health spraying. Similarly, the number of applicators that treat “Other” specific 

crops was few compared to some of the major crops listed on the previous page. Hence, this 

could raise some questions as to whether it is a true and accurate average to what is normally 

conducted in the industry. 

The survey review panel reviewed the information submitted for question # 14 and removed the 

following responses from the calculations because evidence existed that certain respondents did 

not completely understand the question as explained below: 

Response #11 Responder stated that on most crops he never treats with one chemical alone 

Response #14 Shows a daily application of 40,000 acres with one (1) aircraft in (1) day. This is 

not possible with any aircraft in the agricultural aviation fleet. 

Response #49 Canadian operator’s survey responses removed. 

Response #93 answered in yearly not daily terms 

Response #108 placed an “X” next to the crops rather than listing the number of acres treated pre 

day 

Response #227 placed an “X” next to the crops rather than listing the number of acres treated pre 

day. 

Response #261 Canadian operator’s survey responses removed. 

Response #423 Canadian operator’s survey responses removed. 

Response #459 placed an “X” next to the crops rather than listing the number of acres treated pre 

day. 

Response #460 placed an “X” next to the crops rather than listing the number of acres treated pre 

day. 

Response #528 indicated potato as an entry under “Other Crops” and that he/she could treat more 

acres on an “Average” day than on a “Maximum” day. 

The survey panel moved some crops listed by responders as “Other” to the proper crop category 

whenever possible. Otherwise, these were broken down in the “other” crops chart. 
25

 

The survey review panel also set an upper limit on the amount of acres that can be treated in a 

single day with a single aircraft when calculating the average acres on the chart. Because some 

responses were exceptionally high the panel believed that respondents were answering the 

question with multiple planes in mind. The maximum range the panel established was 8,000 

acres per day per aircraft. This is based on a realistic assessment of what the larger planes in the 

agricultural aviation fleet can apply on a daily basis. 

The survey panel also established the following context related to what an applicator associates 

with the “Usual number of acres treated in a day” and the “Maximum number of acres treated in 

a day:” 

Usual number of acres treated in a day – the number of acres that could be treated in a complete 

day of flying with no interruptions due to weather, mechanical, chemical supplies, lack of work 

or other reasons. 

Maximum number of acres treated in a day - the number of acres that could be treated in a 

complete day of flying with the conditions listed above being present and if all the fields were 

large and flat. The likelihood that these conditions are met for an aerial applicator is highly 

unlikely.
1

Appendix A 

Introductory Letter Accompanying Survey

M E M O R A N D U M 

To: United States FAA Part 137 Certificate Holders

From: Dennie Stokes 

NAAA President 

Owner/Operator of Stokes Flying Service, Parkin, Arkansas 

Date: March 20, 2003

Subject: 2003 NAAA Pesticide Use Survey 

Fellow aerial applicators, I have a very important request of you. Please complete the enclosed 2003 Pesticide 

Use Survey and mail or fax it back to NAAA Headquarters at the address or number below by April 28, 2003. 

As you know, crop protection product labels are becoming more and more restrictive for aerial use. Also, the 

number of products available is dwindling. Information collected from this survey will help to address that 

situation. We have developed the survey in an effort to collect actual use data on pesticides applied via aerial 

application. Collecting this data will help counter theoretical data used by the EPA and crop protection product 

manufacturers that can overestimate levels of pesticide exposure. 

I know you all are busy either beginning the 2003 spray season or prepping your equipment to start the season, 

but if you could just take a few minutes to complete the survey it could make a world of difference to both you 

and the industry by helping increase the number of products labeled for aerial application. Completing the two 

page survey shouldn’t take long. I did it myself and it took me under 10 minutes. 

Remember, the value of this survey is only as strong as the type of information you collect and the number of 

completed surveys we can collect. I’m sure a large number in the industry are using closed contained mixing 

loading systems and GPS to minimize worker exposure. I’m sure that a large number in the industry are using 

smokers to gauge wind direction. This is the type of information we need to show the EPA. Also, EPA will not 

give much credibility to the data we collect if only 3% of U.S. operators submit a survey; however, if we have a 

95% industry response rate it adds significant credibility to the data we collected. 

Thanks in advance for completing and submitting your survey back to the NAAA. Believe it or not, your 

individual response will make a difference. 

Enclosure 

1005 E Street, S.E., Washington, D.C. 20003 

Fax: 202/546-5726
2

Appendix A 

Actual Pesticide Use Survey

2003 NAAA Pesticide Use Survey 

Location:

In which State is your aerial application business located? ________ 

Please list the states in which you perform aerial applications. ________________________________ 

Equipment:

How many operating aircraft are used in your aerial application business? ________ 

 How many planes? ________ How many of these planes have a closed cockpit? ________ 

 How many helicopters? ________ How many of these helicopters have a closed cockpit? ________ 

Are your aircraft equipped with smokers to determine wind direction while performing aerial applications? 

(Please check one of the following) Yes No 

If you do use a smoker, how often do you engage it? (Please check all that apply) 

Before an application next to a sensitive area Every swath run Every 2-4 swath runs 

Every 5-7 swath runs Every load 

Other (please explain) ____________________________________________________________ 

____________________________________________________________________________________ 

Mixing/Loading Operations:

What percent of all spray jobs does the pilot of the aircraft also mix and load pesticides? ________% 

If the mixer/loader and the pilot are different individuals, on average how many different aircraft are usually 

supported by that mixer/loader on an average day?_________ 

When Personal Protection Equipment (PPE) is required, do you use disposable or reusable equipment? 

(Please circle one) Disposable Reusable Both 

Does the operation utilize a closed mixing/loading system (mechanical pesticide transfer)? 

Please circle one of the following: Yes No 

When pesticides are mixed and loaded, what percentage of the total mixing/loading jobs use the following 

practices? Please estimate a percentage at the end of each of the following bullets (Total should equal 100%): 

Percentage of mixing/loading jobs spent opening product containers and pouring the pesticide 

formulations into the mixing/loading tank (also known as open pour) ________% 

Percentage of mixing/loading jobs spent transferring pesticides to the mix tank from product containers 

with dry break openings? ________% 

Percentage of mixing/loading jobs spent transferring pesticides to the mix tank from product containers 

without dry break openings? ________% 

Other ________% Please explain ________________________________________________________ 
3

2003 NAAA Pesticide Use Survey 

Page 2 

On average, how many pesticides are typically handled per day by a mixer-loader at your aerial application 

operation? Please provide an actual number in the following space:________ 

In a given year, what is the maximum number of days that a particular type of pesticide would be applied? 

Please provide a number in the space following each classification of pesticide. 

Insecticide: ________ Herbicide: ________ Fungicide: ________ 

Application Practices:

Which of the following do you use to minimize spray drift? (Please check all that apply) 

Drift Control Additives Wind detectors Changes in pressure 

Special nozzles Changes in flight patterns7 Diluting formulations8

When applying pesticides by air, what percent of your applications use: 

 Human flaggers ________% Automatic flaggers ________% GPS ________% Other ________% 

Please complete the following table. For each crop, please indicate the usual and the maximum number of acres 

that you treat on average during a single day, with a single aircraft using a single pesticide.9

Usual Number of Acres 

Treated Per Day, Using a 

Single Aircraft Using a Single 

Pesticide 

Maximum Number of Acres 

Treated Per Day, Using a 

Single Aircraft Using a Single 

Pesticide 

Alfalfa 

Corn, Sorghum 

Cotton 

Forests 

Orchards (Fruit and Nut Trees) 

Pastures and Rangeland 

Rice 

Small grains (Wheat, Barley) 

Soybeans 

Leafy vegetables 

Roots and tubers 

Small fruits (Grapes and Berries) 

Other: _____________________ 

Thank you for completing the 2003 NAAA Pesticide Use Survey. The data you supplied will help NAAA’s 

efforts to increase the number of crop protection products labeled for aerial use. 

Please return your completed survey back to the NAAA by April 28, 2003 at: 

2003 NAAA Pesticide Use Survey 

1005 E Street, S.E., Washington, D.C. 20003 

Fax: 202/546-5726 

 

7 This includes leaving buffer zones on the downwind side of a field during the time of the initial application and returning to complete that portion of the field once the 

wind has shifted. 

8

 Also known as increasing total volume per acre 

9

 NAAA realizes that when making applications to some crops, more than one pesticide will be used. Yet, for purposes of documenting exposure data as outlined by the 

EPA, we need you to answer these questions as if you use a single pesticide in each application load.