AERIAL APPLICATOR EXAM MANUAL 2025/2026
QUESTIONS AND ANSWERS GRADED A+
✔✔VMD is helpful for predicting what? - ✔✔Nozzle tips capacity to provide spray
coverage.
✔✔VMD can also be used to describe in simpler terms? - ✔✔The "spread" of droplet
sizes in a given droplet spectrum.
✔✔Settling velocity is what? - ✔✔The rate at which a spray droplet falls through the air
toward the ground.
✔✔Another term for settling velocity is? - ✔✔Fall Rate
✔✔Settling velocity is generally roughly proportional to what? - ✔✔The square of a
droplets diameter.
✔✔The settling velocity of a 200 micron droplet is? - ✔✔231 feet/minute
✔✔The settling velocity of a 20 micron droplet is - ✔✔2.4 feet/minute
✔✔What can you adjust to alter spray droplet size? - ✔✔-Nozzle type
-Orifice diameter
-Spray pattern angle
-Travel speed
-Spray pressure
-Nozzle mounting angle
✔✔What are a few of the common nozzle types used in aerial application? - ✔✔-Cone
-Fan
-Straight stream
-Rotary atomizers
✔✔Which spray pattern angle is less likely to create drift prone droplets, 80 or 110
degree? - ✔✔80 degree
✔✔Which spray pattern is less likely to produce drift prone droplets, conical or fan? -
✔✔Fan pattern
✔✔What influence does air shear have on spray droplets? - ✔✔Causes droplets to
collide with each other an break up, creating a greater number of drift prone droplets.
✔✔How should nozzles be angled to avoid disruption by air shear? - ✔✔In the same
direction as the air flow, generally straight back for a fixed wing aircraft.
,✔✔When applying pesticides aerially, what can you do to create the lest drift possible? -
✔✔Apply using the slowest speed you can safely operate at.
✔✔Increasing spray pressure causes what? - ✔✔-Spray droplets to become smaller
-A larger proportion of the spray to become drift prone
✔✔To double your spray output using pressure, what sort of increase to pump pressure
must you have? - ✔✔The pressure must be quadrupled
✔✔What other options do aerial applicators have to alter spray output? - ✔✔-Change in
travel speed
-Change in nozzle tips
✔✔"Operational Guidelines" is a catch all category for what? - ✔✔Spray system
features that you can manipulate to manage the size of spray droplets, including:
-Rotation rate of rotary atomizers
-Positioning of a CP nozzles deflector
-Orientation of check valves on a spray boom
-Cross sectional shape of a spray boom
✔✔What is the COMPLETE pesticide product called? - ✔✔Formulation
✔✔Pesticide sprays similar to water result from formulations that either: - ✔✔-Dissolve
in water (WSP,WSL)
-Suspend physically in water (WP,F)
-Suspend chemically in water (EC)
✔✔The best way to manage drift potential is to? - ✔✔Manage and control droplet size
✔✔An Invert Emulsion is? - ✔✔A water soluble substance suspended in an oil diluent
and oil carrier.
✔✔Inver Emulsions have what defining characteristics? - ✔✔-Thick and creamy
-Do not readily evaporate or break up into small droplets
✔✔What is the main purpose of adjuvants? - ✔✔To increase a pesticides effectiveness
or safety
✔✔Spray adjuvants alter what? - ✔✔The PHYSICAL characteristics of a liquid as it
leaves the nozzle, hits the target, or both
✔✔A surfactant is an example of what variety of spray additive? - ✔✔Adjuvant
, ✔✔Adding a surfactant will do what to the characteristics of a spray mix? - ✔✔-Change
the proportion of the spray emitted as a particular droplet size
-Change the total spray droplet spectrum produced by the nozzle tip
✔✔Surfactants act in what way? - ✔✔Reduce the surface tension of a liquid and
promote the formation of small droplets.
✔✔Thickening agents are also referred to as? - ✔✔Viscosity modifiers
✔✔The terms "tank mix" or "spray mix" generally refer to what? - ✔✔A mixture of
several different a.i's, several formulations, and one or more adjuvant that are combined
by at least one diluent or carrier.
✔✔What is Microweather? - ✔✔The weather conditions at ground level or within the
plant canopy at or near the target site.
✔✔What does very stable air indicate? - ✔✔A temperature inversion
✔✔What is a temperature inversion? - ✔✔When the air above is warmer than the air
below. When the air above the target increases in temperature, it rises carrying spray
droplets with it.
✔✔True of False: When temperature increases the potential for spray drift increases? -
✔✔TRUE
✔✔True or False: Unstable air is preferable for spray applications? - ✔✔TRUE
✔✔What is Relative Humidity? - ✔✔RH indicates the extent to which an air sample is
saturated by water.
✔✔Microweather specifically can affects what? - ✔✔The temperature and air turbulence
found here can generate upward air motion, affecting small spray droplets.
✔✔What is the definition of navigation in aerial application? - ✔✔The process of
determining and maintaining a specific course of travel.
✔✔What is landmark navigation? - ✔✔Reliance on the position of fixed objects.
✔✔What is dead reckoning? - ✔✔Elapsed time along a rhumb line at an estimated
constant speed.
✔✔LORAN Stands for what? - ✔✔Long range navigation
✔✔What is LORAN Navigation? - ✔✔Ground generated, hyperbolic radio signals
QUESTIONS AND ANSWERS GRADED A+
✔✔VMD is helpful for predicting what? - ✔✔Nozzle tips capacity to provide spray
coverage.
✔✔VMD can also be used to describe in simpler terms? - ✔✔The "spread" of droplet
sizes in a given droplet spectrum.
✔✔Settling velocity is what? - ✔✔The rate at which a spray droplet falls through the air
toward the ground.
✔✔Another term for settling velocity is? - ✔✔Fall Rate
✔✔Settling velocity is generally roughly proportional to what? - ✔✔The square of a
droplets diameter.
✔✔The settling velocity of a 200 micron droplet is? - ✔✔231 feet/minute
✔✔The settling velocity of a 20 micron droplet is - ✔✔2.4 feet/minute
✔✔What can you adjust to alter spray droplet size? - ✔✔-Nozzle type
-Orifice diameter
-Spray pattern angle
-Travel speed
-Spray pressure
-Nozzle mounting angle
✔✔What are a few of the common nozzle types used in aerial application? - ✔✔-Cone
-Fan
-Straight stream
-Rotary atomizers
✔✔Which spray pattern angle is less likely to create drift prone droplets, 80 or 110
degree? - ✔✔80 degree
✔✔Which spray pattern is less likely to produce drift prone droplets, conical or fan? -
✔✔Fan pattern
✔✔What influence does air shear have on spray droplets? - ✔✔Causes droplets to
collide with each other an break up, creating a greater number of drift prone droplets.
✔✔How should nozzles be angled to avoid disruption by air shear? - ✔✔In the same
direction as the air flow, generally straight back for a fixed wing aircraft.
,✔✔When applying pesticides aerially, what can you do to create the lest drift possible? -
✔✔Apply using the slowest speed you can safely operate at.
✔✔Increasing spray pressure causes what? - ✔✔-Spray droplets to become smaller
-A larger proportion of the spray to become drift prone
✔✔To double your spray output using pressure, what sort of increase to pump pressure
must you have? - ✔✔The pressure must be quadrupled
✔✔What other options do aerial applicators have to alter spray output? - ✔✔-Change in
travel speed
-Change in nozzle tips
✔✔"Operational Guidelines" is a catch all category for what? - ✔✔Spray system
features that you can manipulate to manage the size of spray droplets, including:
-Rotation rate of rotary atomizers
-Positioning of a CP nozzles deflector
-Orientation of check valves on a spray boom
-Cross sectional shape of a spray boom
✔✔What is the COMPLETE pesticide product called? - ✔✔Formulation
✔✔Pesticide sprays similar to water result from formulations that either: - ✔✔-Dissolve
in water (WSP,WSL)
-Suspend physically in water (WP,F)
-Suspend chemically in water (EC)
✔✔The best way to manage drift potential is to? - ✔✔Manage and control droplet size
✔✔An Invert Emulsion is? - ✔✔A water soluble substance suspended in an oil diluent
and oil carrier.
✔✔Inver Emulsions have what defining characteristics? - ✔✔-Thick and creamy
-Do not readily evaporate or break up into small droplets
✔✔What is the main purpose of adjuvants? - ✔✔To increase a pesticides effectiveness
or safety
✔✔Spray adjuvants alter what? - ✔✔The PHYSICAL characteristics of a liquid as it
leaves the nozzle, hits the target, or both
✔✔A surfactant is an example of what variety of spray additive? - ✔✔Adjuvant
, ✔✔Adding a surfactant will do what to the characteristics of a spray mix? - ✔✔-Change
the proportion of the spray emitted as a particular droplet size
-Change the total spray droplet spectrum produced by the nozzle tip
✔✔Surfactants act in what way? - ✔✔Reduce the surface tension of a liquid and
promote the formation of small droplets.
✔✔Thickening agents are also referred to as? - ✔✔Viscosity modifiers
✔✔The terms "tank mix" or "spray mix" generally refer to what? - ✔✔A mixture of
several different a.i's, several formulations, and one or more adjuvant that are combined
by at least one diluent or carrier.
✔✔What is Microweather? - ✔✔The weather conditions at ground level or within the
plant canopy at or near the target site.
✔✔What does very stable air indicate? - ✔✔A temperature inversion
✔✔What is a temperature inversion? - ✔✔When the air above is warmer than the air
below. When the air above the target increases in temperature, it rises carrying spray
droplets with it.
✔✔True of False: When temperature increases the potential for spray drift increases? -
✔✔TRUE
✔✔True or False: Unstable air is preferable for spray applications? - ✔✔TRUE
✔✔What is Relative Humidity? - ✔✔RH indicates the extent to which an air sample is
saturated by water.
✔✔Microweather specifically can affects what? - ✔✔The temperature and air turbulence
found here can generate upward air motion, affecting small spray droplets.
✔✔What is the definition of navigation in aerial application? - ✔✔The process of
determining and maintaining a specific course of travel.
✔✔What is landmark navigation? - ✔✔Reliance on the position of fixed objects.
✔✔What is dead reckoning? - ✔✔Elapsed time along a rhumb line at an estimated
constant speed.
✔✔LORAN Stands for what? - ✔✔Long range navigation
✔✔What is LORAN Navigation? - ✔✔Ground generated, hyperbolic radio signals
