January 14, 2021
NAAA eNewsletter

NAAA Leads Pesticide Use Coalition to Save Many Crops’ Dependence on Effective Use of Paraquat

On Monday, NAAA submitted comments to the Environmental Protection Agency (EPA) to argue against aerial restrictions in the agency’s proposed interim decision for paraquat. The proposed interim decision recommended banning all aerial applications of paraquat except for desiccating cotton.


The EPA is required by the Federal Insecticide Fungicide and Rodenticide Act (FIFRA) to review the registrations for all crop protection products every 15 years. Interim decisions are being used by the EPA instead of a full reregistration of a product because the biological evaluations and pollinator protection assessments still need to be completed for most products. The proposed aerial ban was based on faulty drift modeling and a failure to require combining personal protection measures for pesticide handlers. The multiple-use restriction was proposed with the erroneous belief that the aerial application of paraquat is not critical to any part of U.S. agriculture besides cotton production.

NAAA’s comments referenced and included letters of support and data from several state agricultural aviation associations: Arkansas Agricultural Aviation Association, California Agricultural Aircraft Association, Louisiana Agricultural Aviation Association, Mississippi Agricultural Aviation Association, Association of Montana Aerial Applicators and North Dakota Agricultural Aviation Association. Letters of support were also received and included with NAAA’s comments from the Arkansas Agricultural Consultants Association, University of Arkansas System Division of Agriculture, Southern Ag Consulting and the National Alliance of Independent Crop Consultants.

In addition to NAAA’s comments, NAAA authored and submitted a letter written on behalf of grower groups whose members rely on the aerial application of paraquat. These comments highlighted some of the main points from NAAA’s comments and noted all the crops that depend on aerial applications of paraquat, including soybean, sunflower, potato, rice, wheat, corn and dry bean crops. The letter was signed by the Council of Producers and Distributors of Agrotechnology, National Association of Wheat Growers, National Cotton Council, National Sunflower Association, Washington Friends of Farms & Forests, USA Rice and the Association of Washington Aerial Applicators.

NAAA’s comments addressed and questioned, once again, the EPA’s use of the Tier 1 model in AgDRIFT to estimate drift from aerial applications. This model uses many inaccurate assumptions and substantially overestimates the risk of drift associated with modern aerial applications. These faulty assumptions include a smaller than commonly used droplet size, a swath displacement shorter than industry standards, a slight inversion present during the application despite being prohibited on the label, wind speed measured at a height appropriate for ground applications instead of aerial applications and modeling the application to bare ground instead of a standing crop. NAAA referred the EPA to a letter submitted to the EPA’s Office of Pesticide Programs in June 2020 for a detailed analysis of all the Tier 1 model’s inaccuracies and how to use the Tier 3 AgDRIFT model to improve the accuracy of aerial drift estimates.

NAAA also commented on the EPA’s risks of concern related to pesticide handlers. The proposed interim decision for paraquat noted there were inhalation risks to mixers and loaders (based on EPA models). These risks were higher for aerial applications because of the high number of acres that can be treated daily using agricultural aircraft. NAAA proposed requiring both a closed loading system and an elastomeric half facepiece cartridge respirator when mixing and loading paraquat for aerial applications. The EPA recommended this same combination on the recent proposed interim decision for triphenyltin hydroxide (TPTH), which NAAA referenced. NAAA also proposed banning flaggers for aerial applications of paraquat, which according to its industry surveys are no longer used by the industry.

After addressing these concerns, NAAA’s comments turned to the EPA’s assertion that aerial application only accounts for 3% of the total acres to which paraquat is applied. NAAA used data and letters from the associations listed above and data from the California Department of Pesticide Regulation provided by CAAA to refute this, proving that aerial application of paraquat is critical for, among other things, desiccation of soybeans and control of herbicide-resistant weeds, particularly in the southern U.S.

The full comments NAAA submitted in defense of the safety and importance of aerial applications of paraquat can be read here. NAAA will be commenting on numerous registration review documents in 2021, including a proposed interim decision for chlorpyrifos and endangered species assessments for glyphosate. NAAA remains committed to ensuring your operation has access to the products your customers demand be applied aerially.

National Air and Space Museum Greenlights Installation of Dusty Crophopper Ag Plane

Dusty Crophopper was immortalized on the big screen in the Disney animated films Planes and Planes: Fire & Rescue. Now America’s favorite ag plane is going to be immortalized at the Smithsonian Institution’s National Air and Space Museum’s Udvar-Hazy Center. NAAA received the official confirmation from the National Air and Space Museum’s general aviation curator on Wednesday.

The aircraft is a Dusty Crophopper-adorned Air Tractor AT-301/400A owned by Rusty Lindeman of Rusty’s Flying Service in Texas. Lindeman agreed to donate the aircraft and Disney signed off on it if the National Air and Space Museum would be willing to accept it. NAAA brokered the arrangement between Lindeman, the National Air and Space Museum and Disney Enterprises to add the Dusty Crophopper character likeness aircraft to the museum’s collection of ag aircraft on display at the Udvar-Hazy Center.

In an email informing NAAA and Lindeman of the good news, Dorothy Cochrane, the general aviation curator, stated, “The suitability of the Air Tractor was recognized from the start, it just required internal determination of display or storage capability.”

It is no longer a matter of if but when Dusty Crophopper will be installed in the museum. Three-fourths of the air and space craft at the National Air and Space Museum on the Mall in Washington have been temporarily relocated to the Udvar-Hazy Center in Chantilly, Virginia, while the D.C. location undergoes renovations. In addition, both museums have been closed to the public during the pandemic. It is possible Lindeman’s aircraft could be in place for the National Air and Space Museum’s innovations day at the Udvar-Hazy Center in June, but whether the event takes place will be based on federal and Smithsonian guidelines for reopening the museums and reviving on-site public programming.

NAAA is hopeful that the Dusty Crophopper aircraft can be on display starting on or near the 100th anniversary of the first application by a propelled aircraft on Aug. 3, 2021.

NAAA Closes Out 2020 and Begins 2021 Comments to EPA to Protect Pesticide Products for Aerial Application

On Dec. 22, NAAA submitted comments to the Environmental Protection Agency (EPA) on the final pesticide registration review documents for 2020. The first of the 2021 registration review comments were submitted on Jan. 4. The EPA is required by the Federal Insecticide Fungicide and Rodenticide Act (FIFRA) to review the registrations for all crop protection products every 15 years. The comments submitted on Dec. 22 dealt with risk assessments that the EPA conducts for each active ingredient being reviewed. The comments submitted on Jan. 4 were on proposed interim decisions, which are being used by the EPA instead of a full reregistration of a product because the biological evaluations and pollinator protection assessments still need to be completed for most products.

The risk assessments are the “first round” of documents written by the EPA during the pesticide registration review process. They rely heavily on models to assess the risks the pesticides pose to the environment and human health. The human health risk assessments model the risks to consumers, bystanders and pesticide handlers. The proposed interim decisions are the last phase of the review process. They use the risk assessments as basis for deciding whether a product should be reregistered and what restrictions should be placed on how it is used. While risk assessments may find a risk of concern related to aerial applications of a product, it is the proposed interim decision that might place restrictions on the use of aerial applications.

The proposed interim decisions NAAA commented on were for lambda-cyhalothrin and gamma-cyhalothrin, methomyl, myclobutanil, naphthalene acetic acid, salts, ester, acetamide, and triphenyltin hydroxide (TPTH). The decisions for lambda-cyhalothrin and gamma-cyhalothrin found risks of concern to mixers and loaders for aerial applications and proposed banning the aerial application of gamma-cyhalothrin to high-acreage field crops, which NAAA opposed citing the importance of aerial application for treating these crops. NAAA suggested the use of both a closed loading system and an elastomeric half facepiece cartridge respirator to reduce the risk to mixers and loaders. The proposed interim decision also recommended a buffer zone near aquatic sites, which NAAA indicated needs to be wind direction-based, as drift cannot move upwind. NAAA also opposed a maximum wind speed of 10 mph and proposed 15 mph instead, citing numerous labels and interim decisions that allow aerial application in winds speeds up to 15 mph.

In comments on the proposed interim decisions for methomyl, NAAA made the same arguments in favor of wind direction-based buffer zones and against a 10 mph wind speed restriction. The label statements proposed by the EPA in the interim decisions for myclobutanil and naphthalene acetic acid, salts, ester and acetamide were acceptable, so NAAA commented as such. The proposed interim decision for triphenyltin hydroxide (TPTH) recommended requiring the use of both a closed loading system and an elastomeric half facepiece cartridge respirator for mixers and loaders of aerial applications; NAAA agreed with this requirement. NAAA also argued in favor of wind direction-based buffer zones and against a 10 mph wind speed restriction for TPTH.

The risk assessments NAAA submitted comments for on Jan. 4 were for difenoconazole, fenbuconazole, mesotrione, pyrasulfotole, tembotrione, thiram, tolfenpyrad, topramezone and ziram. All of the risk assessments were done using the Tier 1 model in AgDRIFT to estimate drift from aerial applications. This model uses many inaccurate assumptions and substantially overestimates the risk of drift associated with modern aerial applications. These faulty assumptions include a smaller than commonly used droplet size, a swath displacement shorter than industry standards, a slight inversion present during the application despite being prohibited on the label, wind speed measured at a height appropriate for ground applications instead of aerial applications and modeling the application to bare ground instead of a standing crop. NAAA referred the EPA to a letter submitted to the EPA’s Office of Pesticide Programs in June 2020 for a detailed analysis of all the inaccuracies of the Tier 1 model and how to use the Tier 3 AgDRIFT model to improve the accuracy of aerial drift estimates. A few of the risk assessments did examine the use of larger spray droplets in order to reduce drift. NAAA supported this concept but pointed out droplet size is only one variable in the AgDRIFT model and that the EPA needs to address all of NAAA’s concerns with Tier 1, not just droplet size.

NAAA will be commenting on EPA registration review documents throughout 2021 and into 2022. NAAA commented on pesticide registration review documents for 77 pesticide active ingredients in 2020 and expects to comment on a minimum of 50 in 2021, including paraquat, glyphosate and chlorpyrifos.

This work reiterates the importance of supporting NAAA’s efforts through your membership. Your operation depends on products labeled for aerial application, and you depend on NAAA for ensuring you have access to those products.

FAA Drone Remote Identification Rule Finalized; Operations Over People and at Night Allowed

The Federal Aviation Administration (FAA) 14 CFR Part 89 final rule on the remote identification (RID) of unmanned aircraft systems (UAS) is expected to be published in the Federal Register this month. The rule goes into effect the same time as a rule that amends 14 CFR Part 107 to allow operations of UAS over people and at night.

Remote Identification is hailed as the next incremental step toward further integration of UAS in the National Airspace System. It has been further described as a digital license plate and will be helpful to law enforcement and regulators. There have been situations where unmanned aircraft were not operated legally; however, no enforcement action was taken because it could not be determined with certainty who was operating the UAS or where it was operating. The new rule requires drones to be equipped with technology that will determine a drone’s location and the time it is operating in specific locations. NAAA has been active in advocating drones half a pound or greater be tracked and identified long before the FAA issued its proposed rule in the spring of 2020. You can read those NAAA comments here and the corresponding March 2020 eNewsletter article here.

NAAA has also been pushing for the FAA to require drone sense-and-avoid technology and ADS-B technology to better ensure the safety of manned aircraft from drones; however, that is not a use that will be required as a result of this rule. Under this RID rule, drones will be required to broadcast a signal that includes, among other information, the UAS’s ID serial number, latitude/longitude, altitude, velocity, emergency status and time mark. The identification of the owner/operator of the serial-numbered UAS will only be available to law enforcement and regulatory agencies.

The specific frequency band of the broadcast signal is not specified other than it must be compatible with personal wireless devices such as tablets or phones using Wi-Fi or Bluetooth. The signal strength is required to be optimized to allow reception by as many devices as possible. With only a few exceptions, RID is required for all drones over 0.55 pounds operating outside of an enclosed structure. This is a requirement that NAAA has promoted and was successful in obtaining.

Included in this rule is a prohibition against most UAS using ADS-B Out. This is to prevent the ADS-B system from becoming overwhelmed. NAAA continues to encourage UAS to incorporate ADS-B In, which would enhance safety by informing the UAS operator when an ADS-B out equipped manned aircraft is in the area and obligate them to give the right of way to the manned aircraft as required by Part 107. Newly manufactured unmanned aircraft must meet the requirements of this rule beginning 18 months after publication of the rule in the Federal Register. The operational compliance date for previously manufactured and newly manufactured unmanned aircraft is 30 months after publication.

UAS Operations over People will be allowed by the amendment to 14 CFR 107. The operations have to fit into one of four categories. Each category has different requirements and risk mitigations. The mitigations range from weight limitations to rotating parts being covered to the requirement for a Part 21 airworthiness certificate. Most categories require RID. To read the full mitigation requirements and categories, click here.

UAS Operations at Night are also allowed, which was previously prohibited by Part 107. To qualify for night operations, The UAS must have strobe type anti-collision lighting that is visible for at least 3 miles. The remote pilot operating the UAS is required to have an updated knowledge test to ensure familiarity with the risks and appropriate mitigations for nighttime operations. To read more about UAS operations at night, click here.

NAAA commented on the over-people and at-night rule in March of 2019 when it was first proposed. You can view those comments here. NAAA comments were specifically mentioned in the FAA’s final rule:

NAAA voiced concern about pilot difficulty of spotting a small, unmanned aircraft while the pilot is operating at a very low altitude in what is already a high task load environment. They pointed to a 2015 test conducted by the Colorado Agricultural Aviation Association, which determined that it was difficult for pilots who conduct agricultural aviation operations to detect and track a small, unmanned aircraft at the same time as maneuvering their aircraft for agricultural operations. Pilots operating manned aircraft at low altitudes would experience difficulty in identifying small, unmanned aircraft operating at night, but as discussed previously, numerous mitigations exist to decrease the likelihood of a midair collision.
While the FAA did not completely agree with all of NAAA’s comments, they were definitely taken into consideration.

NAAA continues to work on UAS issues stressing safety to manned aircraft by advocating for technology that will eventually evolve into a traffic management system directing UAS away from manned aircraft. Currently, ADS-B is the only available electronic technology for traffic deconfliction. NAAA encourages manned aircraft to install ADS-B In and Out and for UAS to have ADS-B In. In 2020 the leading drone manufacturer—DJI—started installing ADS-B receivers in all of its UAS. NAAA also pushes for UAS to have high-visibility paint schemes and strobe lighting for both day and night operations.

NAAA Comments to FAA on Companies Using Drones Requesting Exemptions from Aviation Safety Regulations

Last week, NAAA submitted formal comments to the Federal Aviation Administration (FAA) opposing requests from BNSF Railway and Phoenix Air Unmanned for relief from aviation safety regulation requirements under 14 CFR Parts 91 and 61.

BNSF Railway is requesting relief from parts 61.113 (private pilot privileges), 91.7 (Airworthiness), 91.113 (Right of Way), 91.119 (Minimum safe altitudes), 91.121 (altimeter settings), 91.151 (minimum fuel requirements), 91.405 (Maintenance required), 91.407 (maintenance return to service), 91.409 (Annual Inspection) and 91.417 (maintenance records). BNSF’s request for relief states that unmanned aircraft systems (UAS) less than 55 pounds at takeoff would be used for Beyond Visual Line of Sight (BVLOS) operations. NAAA submitted comments opposing the requested relief, documenting the lack of proven technology that would safely allow BVLOS operations to operate and not interfere in the low altitudes that manned agricultural aircraft operate. NAAA also reiterated that UAS must give manned aircraft the right of way as required if this UAS was operated under Part 107—FAA regulations specific to UAS under 55 pounds. Also of concern in the requested relief and opposed by NAAA was a request to allow a single remote pilot in command (RPIC) located remotely to operate up to five unmanned aircraft simultaneously. This indicates an overreliance on computer software for BVLOS, again, without any proven safety technology.

Phoenix Air Unmanned is requesting relief from parts 61.113 (private pilot privileges), 91.7 (Airworthiness), 91.113 (Right of Way), 91.119 (Minimum safe altitudes), 91.121 (altimeter settings), 91.151 (minimum fuel requirements), 91.405 (Maintenance required), 91.407 (maintenance return to service), 91.409 (Annual Inspection) and 91.417 (maintenance records). In the Phoenix Air Unmanned request, the company does not give specifics of whether its intended operation is within line of sight or beyond line of sight, but it does state that the maximum takeoff weight of its UAS is up to 192 pounds. This is a weight that falls above the weight allowed under Part 107. Since specifics of the intended operations were not included in the request, NAAA submitted comments similar to the BNSF comments while stressing the damage that a heavier UAS would do in a collision.

NAAA is aware of the functions that might be accomplished by UAS. At the same time, protecting the safety of current and future users of the national air space is mandatory. Allowing UAS operations without adequate sense-and-avoid technology is a danger to not only low-altitude manned aircraft but all manned aircraft.

NAAA Signs on to GA Industry Letter Requesting a Third Extension to FAR Relief

Last week, NAAA signed on to a letter with six other aviation associations requesting a third extension to SFAR 118. This special regulation provided relief to affected pilots, aircraft owners and operators to safely continue their important role to the U.S. and worldwide economy during the COVID-19 pandemic. SFAR 118 was first issued at the end of April 2020. It has been extended twice since then, with the most recent extension expiring at the end of January.

Each of the extensions covered slightly different provisions of the FARs for different amounts of time. The last extension expiring this month provides a two-month grace period added to medical certification and pilot flight reviews. It is important to note that the extensions were not cumulative. Certifications still expire, but either two or three months after the original expiration date.

An industry survey NAAA conducted in September 2020 showed that 10% of our members still had trouble getting their medical exam due to the pandemic.

The Federal Motor Carrier Safety Administration’s regulatory relief expired Dec. 31, 2020. This agency has not indicated yet if it intends to provide further extensions.

NAAA was one of the first entities to push for regulatory relief and ensured that agricultural aviation was considered an essential service since the COVID-19 pandemic and shutdown effects last March. This “essential” designation has kept the industry working and will continue to be beneficial as the vaccination stage begins now in 2021.


Pilots are allowed to take either the Moderna or Pfizer-BioNtech vaccine with no effect to their medical certificate as long as they do not fly for 48 hours after the dose. As an essential service, ag aviation pilots, operators and other workers should have access to the vaccine after frontline health care workers and vulnerable populations are vaccinated. Different states treat this differently. Click here to find a link to your state’s plan.

Looking for Ways to Market Your Business and the Ag Aviation Industry? Give the Gift of Agricultural Aviation

As NAAA marks the agricultural aviation industry’s 100th anniversary in 2021, spread the gospel of the industry to your farmer-customers by giving them a gift subscription to Agricultural Aviation, the official publication of the National Agricultural Aviation Association! The 2021 magazine issues will cover the aerial application industry’s history over the past century—plus, many articles focus on the professionalism and efficacy of aerial application, which your farmer-customers will be interested in learning or relearning about. A gift subscription is a great way to promote not just your business but the industry as a whole. Maybe you will even inspire someone to look at the industry as a possible new career!

Agricultural Aviation provides current information relevant to aerial application industry trends and regulations, scientific research and technology, as well as NAAA services and government relations efforts pertaining to the agricultural aviation industry.

Agricultural Aviation is published four times per year during each season: Winter, Spring, Summer and Fall. NAAA members automatically receive a complimentary Agricultural Aviation subscription with their membership, but additional subscriptions may be purchased for employees, customers, suppliers, local schools, etc., using this subscription form.

Agricultural Aviation is also available digitally online and via the Agricultural Aviation Magazine App.

Limited Attendance for NAAA and NAAREF Board Meetings Feb. 11-13 Due to Hotel Restrictions

The NAAA and NAAREF Board Meetings Feb. 11-13 are limited in attendance due to the state of Virginia’s social distancing regulations at the hotel. As such, the NAAA and NAAREF Board and Committee Chairs/Co-Chairs are invited to attend the board meeting in person; appointees will only be allowed to participate virtually. Information on how to access the meetings virtually will be forthcoming.

The Hilton Old Town Alexandria will host our February board meetings for NAAA and NAAREF Board and Committee Chairs/Co-Chairs. Click here for a schedule of events (all meetings will take place in ET).

Meetings are open to all NAAA members virtually; if you would like to attend virtually, please email Lindsay Barber for further details.

Hilton Old Town Alexandria

  • Address: 1767 King Street, Alexandria, VA 22314
  • Rate: $153/night plus tax
  • Reservations: Book your room here.
  • Room Block Closes: Jan. 19, 2021, at 5 p.m. ET. Room rates will be higher after block closes and we cannot guarantee rooms after this date.

The Hilton Old Town Alexandria is located directly next to the King Street Metro stop (take either Blue or Yellow Line), which is the second stop south of Ronald Reagan National Airport (DCA). You can view a map of the metro system here.

Update Your Information for 2021 Membership Directory

Have you moved or changed employers since you renewed your 2021 NAAA membership? Allied companies, have you reviewed your company description lately? Ensure your listing in the 2021 NAAA Membership Directory is correct today by logging into your account. If any information has changed, please let us know right away. You can provide your information by:

  • Updating your information at AgAviation.org. Log in using your username and password and update your information under My Profile.
  • Responding to the letter or email that you will receive in January.
  • Emailing your changes to information@agaviation.org.
  • Faxing your changes to (202) 546-5726.
  • Calling the NAAA office at (202) 546-5722.
We must have your updated information by Jan. 20 to guarantee accurate inclusion in the 2021 NAAA Membership Directory!

Set Yourself Up for New Year’s Success by Renewing Your NAAA Membership

Happy New Year! Your 2020 NAAA membership has expired; if you have not already done so, please renew online or by calling the office at (202) 546-5722. As a member of NAAA, you associate with the best and brightest in the agricultural aviation industry and your support is imperative in helping us accomplish our initiatives. We would like to remind you of just a few new offerings NAAA has recently released, such as:

  • Ensuring your aerial application business and job is ESSENTIAL during COVID-19 and extending license expirations due to quarantine shutdowns. Check out our COVID-19 Resources webpage. 
  • Offering legal services on Federal Transpiration Laws to Operator and Pilot Members.
  • Receive the 2019 NAAA Operator and Pilot Survey Report which is chock-full of key statistics providing a healthy status of the U.S. aerial application industry. 
  • Don’t forget to take advantage of financial incentives such as NAAA’s Recruitment Rewards Program.
  • Our NAAA Membership Directory is your one-stop shop where you can find professional members that might be looking for help or offering help and a plethora of qualified allied services in the industry.
  • Stay up to date on the latest issues affecting your profession through the NAAA eNewsletter, Agricultural Aviation magazine and exclusive member resources online such as our Media Relations Kit.

NAAA is dedicated to protecting and advancing the needs of the industry by improving the public's perception of the aerial application industry and spearheading the industry's environmental stewardship and safety initiatives. If you haven’t gotten a chance to review all our accomplishments this past year in the 2020 NAAA Membership Directory, you can download our Annual Report.


We appreciate your membership as it will help us continue to fight and win to keep aerial application as an essential service during the current global pandemic and on important issues like unfair user fees and taxes; requiring tower marking requirements; and ensure the safe integration of drones into the national airspace; and advocating that EPA keeps a healthy inventory of crop protection products for aerial use without unnecessary restrictions. Your membership helps us better represent your interests.

Ag Aviation's Centennial Year Kicks Off with New Trailer

One hundred years ago, on Aug. 3, 1921, an aerial crop dusting experiment spawned the birth of the agricultural aviation industry. To kick off NAAA’s yearlong centennial celebration, watch this short video on the industry's legacy after a century of agricultural aviation!


NAAA Presidents Appear on Business of Ag Podcast

NAAA’s 2020 and 2021 presidents discussed the past, present and future of aerial application on Damian Mason’s Business of Agriculture Podcast. Darren Pluhar and Mark Kimmel, the ’20 and ’21 presidents, taped the Dec. 28 episode on the trade show floor of the 2020 Ag Aviation Expo, shortly after Mason spoke at the expo’s Kickoff Breakfast. Topics covered in the episode include the future of aerial application via manned and unmanned aircraft, the impact of consolidation, regulations, cropping changes and the evolution of agriculture as seen from the cockpit. Watch the informative episode below or listen to it on SoundCloud.



The Business of Agriculture Podcast covers the business of food, fuel and fiber through interviews with industry professionals and commentary from the podcast’s host.

EPA’s Aircraft Greenhouse Gas Emission Standards in Effect as of Jan. 1 (Current Ag Aircraft Outside of Rule)

As reported in the July 30, 2020 NAAA eNewsletter, the Environmental Protection Agency (EPA) is adopting greenhouse gas (GHG) emission standards applicable to certain classes of engines used by certain civil subsonic jet airplanes. In 2016 the Obama administration signed on to the U.N.’s International Civil Aviation Organization (ICAO) plan to reduce GHG emissions from jet and turboprop aircraft. The final rule, now in effect, regulates (among other types) turboprop aircraft with a takeoff mass greater than 8,618 kilograms (18,959 pounds). This weight puts all the current agricultural aircraft outside of the rule. The rule requires carbon dioxide (CO2) and nitrous oxide (N2O) emissions to be mitigated by increased efficiency and carbon offsets.

The GHG standards that apply to new type design airplanes are expected to go into effect in January and will go into effect on or after Jan. 1, 2028, for in-production airplanes. They do not apply to already manufactured airplanes currently in use. New type design airplanes are newly developed airplane designs that have not previously been type certificated by the Federal Aviation Administration (FAA) and have not been built or flown yet. In-production airplanes are new airplanes with designs that have already been type certificated by the FAA and are already in production and will continue to be produced and sold after the standards’ effective date.

While some are touting this move as a way to ensure that U.S. built aircraft are competitive globally, NAAA is watching this development closely. These rules have a way of expanding, as many environmentalists feel the ICAO aircraft standards are not rigorous enough. NAAA has the data that shows modern agriculture, of which ag aviation is a critical component, plays an important role in reducing GHG emissions.

Beware of Jet Fuel/Diesel Fuel Deliveries with Possible Diesel Exhaust Fluid Contamination

Ten to 12 Pratt & Whitney Canada turbofan engine events on corporate jets have occurred over the past two years involving power rollbacks with the inability to regain power. In one instance, the corporate jet lost power in both engines. The aircraft that experienced the complete loss of power was able to glide to a runway and land safely. Upon investigating the incidents, the FAA attributed the cause of the engine problems to contaminated fuel.

Somehow diesel exhaust fluid (DEF), a liquid used to reduce the amount of air pollution created by a diesel engine, ended up in jet fuel at several airports and got dispensed into the aircraft. Although the majority of PT6A ag engines are unlikely to be affected by this problem, it is worth being aware of and speaks to the importance of fuel integrity.

These refuelings happened at several different fixed-base operations (FBOs) around the country. Shortly after departure from those airports, the DEF in the jet fuel reacted and started to plug orifices in the engines’ fuel control units (FCUs). Investigations of each fuel control unit revealed large amounts of urea partially or completely plugging fuel-related orifices in the fuel control. (DEF is an aqueous urea solution made with 32.5% urea and 67.5% deionized water.)

These aircraft all were serviced with Jet A fuel, and somehow, diesel exhaust fluid (DEF). These refuelings happened at several different fixed-base operations (FBOs) around the country. Within 20 to 30 minutes after takeoff, each jet had an impending fuel bypass caution light illuminate, and each aircraft had an engine experience an uncommanded rollback to idle thrust. One aircraft experienced a dual engine rollback. None of the engines that had a rollback were able to recover power with a throttle push. All aircraft were able to glide to a runway and land safely.

In discussions between Fletcher Sharp, the director of propulsion on NAAA’s board, and vendors that specialize in repair/overhaul of fuel control units, the general sentiment was that PT6 engines fitted with Bendix/Honeywell FCUs (PT6A-20 through and including PT6A-45 series) most likely would not experience any issues if DEF contaminated the fuel.

The larger PT6A-140AG, -60AG, -65AG and -67AG engines all have Woodward FCUs. Those might be prone to problems, mainly during winter storage, because unlike the smaller Bendix/Honeywell FCUs, the Woodward fuel control unit is always full of fuel. Fuel contaminated by DEF in the fuel control unit and left alone without any ground runs during the offseason could show signs of sticking control valves, corrosion or both. Urea is extremely corrosive if left alone, and corrosion is not covered under Pratt & Whitney Canada’s warranty.

DEF only goes with diesel fuel. It is not for use in any other fuel product. However, most diesel fuels are very similar to jet fuels. Operators should closely monitor fuel product at delivery to their fuel farms to ensure DEF is not mixed with their fuel.


 P&WC Service Bulletin 13244 for the -60AG and -65AG and Service Bulletin 14504 for the -67AG and -67F engines address approved fuels and additives. The -140AG fuel and additive information is in the -140AG engine maintenance manual. If any engine issues arise that could be related to use of unapproved fuels or additives, Pratt & Whitney Canada’s warranty would most likely be null and void.

Pilots Approved for Moderna COVID-19 Vaccine with 48-Hour Flight Restriction

Two days after FDA approval of the Moderna COVID-19 vaccine, the FAA stated: “Holders of FAA-issued Airman Medical Certificates or Medical Clearances may receive the Moderna COVID-19 vaccine; however, a 48-hour ‘No Fly/No Safety-Related Duty’ interval must be observed after each dose.” The Moderna vaccine requires two doses, which must be spaced 28 days apart.

As NAAA reported in the December 17, 2020 eNewsletter, this action was expected following a similar statement last week regarding the Pfizer-BioNTech vaccine.

The 48-hour no-fly restriction is the same as was issued for the Pfizer-BioNTech vaccine. Individuals holding an Airman Medical Certificate are prohibited from performing flight crewmember duties if they do not meet medical certification requirements, including those related to adverse events from medications that render them unable to perform such duties.

NAAA has been successful throughout the pandemic to ensure that the industry is considered an essential service. As such, those involved in agricultural aviation should have an opportunity to receive the COVID-19 vaccine once frontline health care workers and vulnerable populations have received the vaccine.