Low-Level Towers and Ag Aviation

Unmarked, low-level obstacles have been a top concern of the aerial application industry when it comes to aviation safety. Wind energy turbines, meteorological evaluation towers (METs), real time kinematic (RTK) towers, and other ground-affixed obstructions are, in many instances, not marked or lit in or near agricultural areas where aerial applicators are flying.  This can result in them being difficult if not impossible to see when flying around them. From 2010 through 2021 there were 19 part 137 accidents involving towers and sadly 9 of those resulted in fatalities. One of the easiest and most cost-effective ways for legislators to save lives is by setting safety standards for all towers over 50 feet to be marked, lit and their coordinates logged in a publicly accessible database.

NAAA has been aggressively tackling the unmarked, low-level tower threat (including METs) the last several years, including working through both Congress and the FAA.

Marking Efforts Through Congress— NAAA was successful in working with Congressman Sam Graves (R-MO), now the ranking member of the House Transportation & Infrastructure Committee, to include legislative language in the 2016 FAA Reauthorization extension bill to require the marking of towers between 50-200 feet with an above-ground base of 10 feet or less in diameter so long as the towers are on undeveloped land, among other conditions. The bill also requires that towers be logged in a FAA database accessible to agricultural aviators.

After this occurred the telecommunications industry claimed to have been taken by surprise by these changes and successfully pushed to lighten their marking requirements in the 2018 FAA Reauthorization bill. The telecommunications industry claims unmarked towers don’t pose a threat to low-altitude aviators and the cost of marking towers is too high, as is the risk to tower workers who would have to mark existing towers. At the request of Congress, NAAA worked to find a more cost-effective alternative to the marking requirements. NAAA developed an alternative that in lieu of painting, a tower could be marked by strategic placement of fluorescent ball markers and/or the installation of lights. This approach was not accepted by the telecommunications industry.  As a result Congress developed its own compromise and the 2018 FAA Reauthorization contained language that solely requires marking or the logging into a database of non-MET towers in rural areas between 50 and 200 vertical feet and an above-ground base up to 10 feet in diameter. METs, still must be both marked and logged.

Additionally, in the summer of 2019 NAAA conducted a thorough analysis of tower -related accidents across all sectors of aviation and discovered from 2008 to 2018, there were 40 accidents and incidents from collisions with METs, communication towers, towers supporting power lines and wind turbines resulting in 36 fatalities. This includes 22 Part 137 accidents and nine part 137 fatalities. NAAA used this startling new data to encourage landowners and tower companies to properly mark their towers and has taken this information to Congress as further evidence communication towers also need to be properly marked.

NTSB Recommendations – In addition to NAAA’s tower marking efforts, the National Transportation Safety Board (NTSB) made recommendations to the FAA in 2013 to: (1) create and maintain a publicly accessible national database for the required registration or all meteorological evaluation towers; and (2) amend 14 Code of Federal Regulations Part 77 to require all meteorological evaluation towers be registered, marked, and—where feasible—lighted. In late 2018 the NTSB issued newly revised Safety Alert SA-016 titled “The Hazards of Unmarked Towers,” urging pilots to be vigilant for unmarked meteorological evaluation towers (METs) and other unmarked towers such as GPS functionality and telecommunications towers. 

Emerging Hazards – A more recent potential hazard in some parts of the country is the erection of RTK towers for use with farm and construction equipment auto-steering that can likewise be deployed at any location in a matter of hours. The RTK towers are like METs in their difficulty to see, but usually measure only 105 feet in height and are supported with guy wires. Communication with one of the primary owners of these towers in the Upper Midwest told a representative of NAAA they did not intend to mark or light their towers because regulations did not require it. In some areas, ag operators have been reluctant to openly oppose these towers because they are desired by their farmer customers. Regardless, safety dictates the towers should be marked for maximum visibility for the safety of low altitude aviators.

Without sensible placement and proper marking of all types of towers and other obstacles occurring in low-altitude airspace in agricultural areas, farmers may be at risk of losing important aerial application services performed on their cropland. Towers erected directly in the flight path of aerial applicators’ landing strips and/or hampering the accessibility of treatable cropland could literally shut down aerial application operations. This would detrimentally affect, in some instances, the only method farmers have available to them when the time comes to apply seeds, fertilizers and crop protection chemicals, necessary to foster crop growth, let alone other services low-level aviators contribute to benefit the public. In that vein, NAAA launched the “Towers Policy” section of its website, which provides tools to educate the public on the dangers of unmarked towers to pilots of low-altitude aircraft; and addresses the safety and accessibility concerns associated with wind turbines. The tools illustrate how poor tower marking and improper wind turbine siting put pilots’ lives and farmers’ livelihood at risk. NAAA has urged federal agencies that help to subsidize and promote wind energy, such as the USDA and DOE, to help in its campaign to inform the public that improper placement of wind towers may pose significant dangers to low-altitude aviation operations and may negatively affect agricultural production.

USDA Rural Broadband Grant Recipients- as the USDA develops financing, policy and other aspects related to rural broadband development, the conference report of the enacted legislation directs the USDA to take into account existing FAA requirements for marking towers, specifically the law requiring towers below 200 feet in rural areas be marked or logged into a database. NAAA worked to have this provision included in the report.  The report recognizes this is important “to protect the safety of aerial applicators, aerial firefighters, public health applicators, medevac units, law enforcement and other low-altitude aircraft.” This is particularly important not just for rural broadband programs specified in the 2018 Farm Bill, but also for any potential infrastructure packages Congress might consider. NAAA created education materials detailing tower marking laws and best practices that USDA will distribute to recipients of loans and grants awarded by under the USDA’s Re-connect program.

While the national database of low-altitude towers has yet to be completed, there are some resources ag aviators can utilize. Both the Daily Digital Obstacle File (published every business day) and the Digital Obstacle File (published every eight weeks) can provide information about potential flight path obstacles before takeoff.

The FAA receives obstacle information from a variety of sources both inside and outside the FAA. The FAA then evaluates the obstacle data based on its analysis of supporting documentation and assigns an accuracy code.

These include many obstacles of interest to aviation users, including obstructions above or below 200 feet AGL, mainly near airports. Thanks in part to a new automated process, low-altitude obstacles can be added to this database more quickly making it a valuable resource for agricultural aviators, however, for now all structures below 200 feet not near airports are only submitted to this database voluntarily. The tower marking requirements for communications towers under 200 feet in rural areas will make this database far more robust.

Additionally, FAA’s Obstruction Evaluation / Airport Airspace Analysis (OE/AAA) has developed a system website, users can now be notified when a structure is proposed in an area that might impact operations allowing you to petition the local zoning authority to build the tower(s) elsewhere or mark it to ensure it will be easily visualized for low-flying aviators. You can sign up for alerts here.

In early December of 2020 NAAA had contact with Balmoral Engineering, an Australian company that manufactures a rotating multi color wire marking device.  Preliminary discussions with their US distributer, Sicame USA, indicated that they were willing to work together on some type of strategy to promote the use of the device with power distribution companies.  Balmoral Engineering is also researching to see if their device would work with angled wires such as tower guy wires. 

NAAA has had requests for assistance to members who are experiencing obstructions encroaching on their private airports.  NAAA has provided information to them and the offer of legal assistance from John Wright.  The FAA does not get involved in issues involving obstructions to private airports.  This is a land use issue and NAAA encourages members to become involved in state and local zoning. The registration of airports with the FAA is encouraged as this provides a method to legitimatize claims to zoning authorities that private airports should be given consideration for relief from obstructions. Currently registered airport owners should also go to this site occasionally to review your airport information and ensure that your airport is listed as “operational.”  
Updates Since the 2021 October Board Meeting:  NAAA continues to stay in contact with the FAA regarding the expected NPRM on low level obstruction marking.  The expected date for the NPRM continues to be pushed back and most recently the FAA was not able to give a date, saying the FAA has higher priorities.  NAAA is pursuing action through legislative representatives to put pressure on the FAA to act on this important safety issue.  House Transportation & Infrastructure Committee Ranking Member Sam Graves (R-MO) is pressuring the FAA to expedite their completion of the tower marking/logging rule. In a September 28th 2021 letter to the FAA, Representative Graves reminded the FAA in no uncertain terms that the FAA is “blatantly ignoring this congressionally directed and long-overdue safety-critical rulemaking.”  In addition, NAAA has made attempts to include language within the infrastructure and reconciliation bills that are making their way through Congress to include language that would bring communications under marking and lighting requirements for towers between 50-200 feet in rural areas with a ten foot diameter or less.

At the 2021 Expo, NAAA Safety Committee Chairman Dale Patterson and NAAA staff met with Gary Conn of Sicame USA to discuss strategies for getting wires and cables marked with the RotaMarka. It was decided that the quickest way to reach the most troublesome wires was to first work with the rural electrical cooperative power companies to promote marking of power lines.

Updated February 2022.

This document is intended for NAAA members’ review only. It is not intended for publication. NAAA requests that should any party desire to publish, distribute or quote any part of this document that they first seek the permission of the Association.