`[Federal Register Volume 89, Number 222 (Monday, November 18, 2024)]
[Proposed Rules]
[Pages 90627-90646]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2024-26741]


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 Proposed Rules
                                                 Federal Register
 ________________________________________________________________________
 
 This section of the FEDERAL REGISTER contains notices to the public of 
 the proposed issuance of rules and regulations. The purpose of these 
 notices is to give interested persons an opportunity to participate in 
 the rule making prior to the adoption of the final rules.
 
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  Federal Register / Vol. 89, No. 222 / Monday, November 18, 2024 / 
Proposed Rules  

[[Page 90627]]



DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 77

[Docket No. FAA-2024-2574; Notice No. 25-01]
RIN 2120-AK77


Requirements To File Notice for Meteorological Towers and Other 
Wind Energy Systems

AGENCY: Federal Aviation Administration (FAA), DOT.

ACTION: Notice of proposed rulemaking (NPRM).

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SUMMARY: The FAA is proposing to amend requirements applicable to 
meteorological towers and permanent wind energy systems. This rule 
would require any person that owns (sponsor) any proposed, altered, or 
existing meteorological tower to file notice with the Federal Aviation 
Administration (FAA) if the highest point of the structure is at least 
50 feet above ground level (AGL) up to and including 200 feet AGL at 
its site. The FAA is also proposing marking requirements for 
meteorological towers constructed or altered after the effective date 
of a final rule if the highest point of the structure is at least 50 
feet AGL up to and including 200 feet AGL at its site. Additionally, 
the FAA proposes making certain pertinent information about any 
meteorological tower with the highest point of the structure at least 
50 feet AGL up to and including 200 feet AGL at its site available on 
the FAA's official database. The FAA expects these changes to lower the 
collision risk for aircraft during low-altitude operations. Moreover, 
these requirements would partially address two statutory mandates and 
two National Transportation Safety Board (NTSB) recommendations.

DATES: Send comments on or before January 17, 2025.

ADDRESSES: Send comments identified by docket number FAA-2024-2574 
using any of the following methods:
     Federal eRulemaking Portal: Go to https://www.regulations.gov and follow the online instructions for sending your 
comments electronically.
     Mail: Send comments to Docket Operations, M-30; U.S. 
Department of Transportation (DOT), 1200 New Jersey Avenue SE, Room 
W12-140, West Building Ground Floor, Washington, DC 20590-0001.
     Hand Delivery or Courier: Take comments to Docket 
Operations in Room W12-140 of the West Building Ground Floor at 1200 
New Jersey Avenue SE, Washington, DC, between 9 a.m. and 5 p.m., Monday 
through Friday, except Federal holidays.
     Facsimile: Fax comments to Docket Operations at (202) 493-
2251.
    Docket: Background documents or comments received may be read at 
https://www.regulations.gov at any time. Follow the online instructions 
for accessing the docket or go to the Docket Operations in Room W12-140 
of the West Building Ground Floor at 1200 New Jersey Avenue SE, 
Washington, DC, between 9 a.m. and 5 p.m., Monday through Friday, 
except Federal holidays.

FOR FURTHER INFORMATION CONTACT: Brian Konie, Airspace Rules and 
Regulations Team, Air Traffic Organization, AJV-P21, Federal Aviation 
Administration, 800 Independence Avenue SW, Washington, DC 20591; 
telephone: (202) 267-8783; email: [email protected].

SUPPLEMENTARY INFORMATION: The FAA further proposes amending the notice 
requirements for any person that owns (sponsors) a proposed or altered 
permanent wind energy system. The FAA is also proposing to extend the 
expiration date of the Determination of No Hazard to Air Navigation for 
permanent wind energy systems and associated meteorological towers.
    The FAA is also proposing to clarify that, except for structures 
that have received an FAA Determination of No Hazard to Air Navigation 
prior to the effective date of a final rule or any meteorological tower 
with the highest point of the structure at least 50 feet AGL up to and 
including 200 feet AGL at its site for which construction is complete 
prior to the effective date of a final rule, all conditions and 
limitations of any Determination of No Hazard to Air Navigation are 
mandatory, which includes marking requirements. Finally, the FAA 
proposes making several miscellaneous conforming and clarifying 
amendments.

List of Abbreviations and Acronyms Frequently Used in This Document

AC--Advisory Circular
AGL--Above Ground Level
ATC--Air Traffic Control
AWES--Airborne Wind Energy System
DOE--Department of Energy
FCC--Federal Communications Commission
GPS--Global positioning system
NAAA--National Agricultural Aviation Association
NAS--National Airspace System
NTSB--National Transportation Safety Board
OE/AAA--Obstruction Evaluation/Airport Airspace Analysis
SIR--Special Investigation Report
VOR--Very High Frequency Omnidirectional Range

I. Executive Summary

A. Overview of Proposed Rule

    This proposed rule would amend title 14 Code of Federal Regulations 
(14 CFR) part 77, Safe, Efficient Use, and Preservation of the 
Navigable Airspace, as it applies to all existing meteorological 
towers, as well as proposals to construct or alter a meteorological 
tower, with the highest point of the structure at least 50 feet AGL up 
to and including 200 feet AGL at its site.
    The FAA proposes requiring a sponsor \1\ proposing to construct or 
alter a meteorological tower at least 50 feet AGL up to and including 
200 feet AGL at its site to file notice under Sec.  77.9 pursuant to 
Sec.  77.7(b).
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    \1\ The FAA notes that the word ``Sponsor'' is capitalized in 
Advisory Circular 70/7460-1. However, for purposes of this 
rulemaking, the word is lower case.
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    This rule would also require sponsors of existing meteorological 
towers with the highest point of the structure at least 50 feet AGL up 
to and including 200 feet AGL at its site to file notice with the FAA 
within 90 days of the final rule's effective date pursuant to Sec.  
77.9.
    Additionally, the FAA proposes making certain pertinent information 
about any meteorological tower with the highest point of the structure 
at least 50 feet AGL up to and including 200 feet AGL at its site 
available on the FAA's official database, the Digital Obstacle File 
(DOF), available at https://www.faa.gov/air_traffic/flight_info/aeronav/digital_products/dof. The FAA expects that collecting via the 
notice

[[Page 90628]]

and sharing information on proposed, altered, and existing 
meteorological towers in the DOF database will improve situational 
awareness for pilots conducting low-altitude operations.
    In addition to the changes affecting meteorological towers, this 
proposed rule would also add additional requirements addressing 
permanent wind energy systems. The FAA needs these changes to properly 
handle the unique attributes of wind energy systems. The FAA proposes 
the following changes:
     Require notice of proposed construction or alteration of a 
permanent wind energy system at least 90 days before the start date of 
the proposed construction or alteration, or the date an application for 
a construction permit is filed, whichever is earlier; and,
     Amend the expiration date of the Determination of No 
Hazard to Air Navigation under Sec.  77.33 for permanent wind energy 
systems and associated meteorological towers to 36 months after the 
effective date of the determination.
    Finally, this proposed rule would make the following changes, 
clarifying and codifying current agency practice:
     Add a definition of airborne wind energy system (AWES) to 
Sec.  77.3 for consistency with the FAA's final notice of policy; \2\
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    \2\ Airborne Wind Energy Systems (AWES) Policy Statement, 87 FR 
78849 (Dec. 23, 2022).
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     Add a definition of meteorological towers to Sec.  77.3 
for consistency with the FAA's final notice of policy; \3\
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    \3\ Id.
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     Add a definition of sponsor to Sec.  77.3 to clarify the 
scope of applicability;
     Add a definition of wind energy system to Sec.  77.3 to 
clarify the scope of applicability;
     Amend Sec.  77.7 to update the methods available to 
acquire an approved copy of FAA Form 7460-1, Notice of Proposed 
Construction or Alteration;
     Revise the heading of Sec.  77.9, ``Construction or 
alteration requiring notice,'' to ``Notice requirements'' to reflect 
that existing meteorological towers may need to provide notice to the 
FAA;
     Redesignate Sec.  77.11 as Sec.  77.10, and amend to 
identify FAA Form 7460-2, Notice of Actual Construction or Alteration, 
as the form sponsors use to provide supplemental notice;
     Add Sec.  77.11 to require the sponsor to submit 
additional information upon request throughout the aeronautical study 
process, which includes all actions required pre- and post-
determination;
     Add Sec.  77.12 to clarify that, except for structures 
that have received an FAA Determination of No Hazard to Air Navigation 
prior to the effective date of a final rule or any meteorological tower 
with the highest point of the structure at least 50 feet AGL up to and 
including 200 feet AGL at its site for which construction is complete 
prior to the effective date of a final rule, a sponsor must comply with 
any conditions and limitations contained in a Determination of No 
Hazard to Air Navigation including marking requirements that would be 
developed in accordance with the FAA Advisory Circular 70/7460-1, 
Obstruction Marking and Lighting, for proposed or altered 
meteorological towers with the highest point of the structure at least 
50 feet AGL up to and including 200 feet AGL at its site;
     Amend Sec.  77.27 to clarify when an aeronautical study is 
appropriate;
     Add Sec.  77.32 to clarify how a sponsor may request a 
modification or deviation from the marking and lighting requirements 
contained in a determination; and,
     Amend Sec.  77.35 to clarify a sponsor's duty to request 
an extension of the effective period of the determination when the 
original Federal Communications Commission (FCC) completion date needs 
to be extended.
    The FAA is proposing to revise references to ``Airport/Facility 
Directory, Alaska Supplement, or Pacific Chart Supplement'' to ``Chart 
Supplement U.S., Chart Supplement Alaska, or Chart Supplement 
Pacific.''
    The FAA notes that, as discussed in section IV.D. of this preamble, 
the FAA is proposing to revise references to ``you'' to refer to the 
sponsor to make clear to whom ``you'' applies.
    The FAA also notes that, as discussed in section IV.D of this 
preamble, the FAA is proposing to revise references to ``marking and 
lighting recommendations'' to ``marking and lighting requirements'' for 
consistency with the changes in Sec.  77.12.
    The following table summarizes the substantive changes proposed in 
this rule.

                  Table 1--Summary of Proposed Changes
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          CFR Sec.                         Proposed provision
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77.1.........................  Establishes the requirement that all
                                conditions and limitations in the
                                determination are mandatory, including
                                the requirement to mark newly
                                constructed or altered meteorological
                                towers with the highest point of the
                                structure at least 50 feet AGL up to and
                                including 200 feet AGL at its site.
77.3.........................  Add definitions for ``airborne wind
                                energy system (AWES),'' ``meteorological
                                tower,'' ``sponsor,'' and ``wind energy
                                system.''
77.5.........................  A sponsor of a meteorological tower in
                                existence before the effective date of a
                                final rule must provide notice
                                consistent with Sec.   77.7(d).
                               A sponsor proposing any construction or
                                alteration of a meteorological tower
                                with the highest point of the structure
                                at least 50 feet up to and including 200
                                feet AGL at its site must provide
                                adequate notice to the FAA of that
                                construction or alteration pursuant to
                                Sec.   77.7(b).
77.7.........................  Require a sponsor to file notice at least
                                45 days before the start of construction
                                or alteration or the date of application
                                for a construction permit for any new
                                meteorological tower, whichever is
                                earlier.
                               A sponsor must submit FAA Form 7460-1 for
                                any proposed construction or alteration
                                of a permanent wind energy system and
                                associated meteorological towers at
                                least 90 days before the start date of
                                the proposed construction or alteration,
                                or the date an application for a
                                construction permit is filed, whichever
                                is earlier.
                               A sponsor of a meteorological tower that
                                exists prior to the effective date of a
                                final rule with the highest point of the
                                structure at least 50 feet AGL up to and
                                including 200 feet AGL at its site must
                                submit FAA Form 7460-1 within 90 days of
                                the effective date of a final rule.
77.9.........................  A sponsor must file notice of any
                                construction or alteration of a
                                meteorological tower with the highest
                                point of the structure at least 50 feet
                                AGL up to and including 200 feet AGL at
                                its site.

[[Page 90629]]

 
                               If a sponsor has an existing
                                meteorological tower with the highest
                                point of the structure at least 50 feet
                                AGL up to and including 200 feet AGL at
                                its site prior to the effective date of
                                a final rule, the sponsor must file
                                notice consistent with Sec.   77.7(d).
77.10........................  Makes clear that a sponsor must file
                                supplemental notice if otherwise
                                requested by the FAA.
77.11........................  If the FAA requests additional
                                information during any part of the
                                aeronautical study process, pre- or post-
                                any determination, the sponsor must
                                provide that information within 30 days.
77.12........................  Except for structures that have received
                                an FAA Determination of No Hazard to Air
                                Navigation prior to the effective date
                                of a final rule or any meteorological
                                tower with the highest point of the
                                structure at least 50 feet AGL up to and
                                including 200 feet AGL at its site for
                                which construction is complete prior to
                                the effective date of a final rule,
                                sponsors must comply with the conditions
                                and limitations contained in a
                                Determination of No Hazard to Air
                                Navigation. This includes requiring
                                newly constructed or altered
                                meteorological towers with the highest
                                point of the structure at least 50 feet
                                AGL up to and including 200 feet AGL at
                                its site to mark the tower.
77.27........................  The FAA will conduct an aeronautical
                                study when: (1) notice required under
                                Sec.   77.9 has been received, or (2)
                                the FAA determines a study is necessary.
                                All other notices filed outside of these
                                parameters will be screened within the
                                automated OE/AAA system and provided an
                                electronic letter response that
                                indicates that no notice is required for
                                the said proposal or alteration, and
                                thus the FAA has no objections to the
                                proposal.
77.32........................  In order to request a modification or
                                deviation from the marking and lighting
                                requirements contained in a
                                Determination of No Hazard to Air
                                Navigation, the sponsor must submit FAA
                                Form 7460-1, Notice of Proposed
                                Construction or Alteration.
77.33........................  Unless extended, revised, or terminated,
                                each Determination of No Hazard to Air
                                Navigation issued under subpart D of
                                part 77 regarding a proposed permanent
                                wind energy system, including an
                                airborne wind energy system, and
                                associated meteorological towers,
                                expires 36 months after the effective
                                date of the determination or on the date
                                the proposed construction or alteration
                                is abandoned, whichever is earlier.
------------------------------------------------------------------------

B. Summary of Costs and Benefits

    Section 2110 of the FAA Extension, Safety, and Security Act of 2016 
(FESSA),\4\ as amended by section 576 of the FAA Reauthorization Act of 
2018 (FAARA),\5\ mandates the FAA to require the marking of ``covered 
towers'' if they are not included in the database described in section 
2110, except for meteorological towers. Section 2110(a)(2) requires 
that all meteorological towers be marked and included within a 
database. This proposed rule would include meteorological tower 
information in a database as well as require compliance with any 
marking requirements that are conditions and limitations in a 
Determination of No Hazard to Air Navigation for a proposed or altered 
meteorological tower. The proposed rule would partially satisfy the 
mandate concerning meteorological towers without placing undue 
financial burdens on existing towers and partially address two National 
Transportation Safety Board (NTSB) recommendations.\6\ This proposal 
also includes additional amendments that would allow the FAA more time 
to study and determine aeronautical effects and any potential national 
airspace system (NAS) impacts from permanent wind energy systems and 
associated meteorological towers.
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    \4\ Public Law 114-190, sec. 2110; 130 Stat. 623 (Jul. 15, 
2016).
    \5\ Public Law 115-254, sec. 576; 132 Stat. 3391 (Oct. 5, 2018).
    \6\ NTSB Safety Recommendations A-13-16 and A-13-17 (May 2013).
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    Section 2110, as amended by section 576 of FAARA, requires the 
clear marking of towers and their inclusion in a database no later than 
18 months after the date of enactment of the FAA Reauthorization Act of 
2018 or the date of availability of the database, whichever is later. 
Section 2110(a)(1)(A) requires that towers be clearly marked consistent 
with applicable guidance in the advisory circular issued December 4, 
2015 (AC 70/7460-1L). Consistent with the direction provided by section 
2110, the FAA proposes to add new Sec.  77.12, Conditions and 
limitations. This proposal would clarify that sponsors that receive a 
Determination of No Hazard to Air Navigation, except for structures 
that have received an FAA Determination of No Hazard to Air Navigation 
prior to the effective date of a final rule or any meteorological tower 
with the highest point of the structure at least 50 feet AGL up to and 
including 200 feet AGL at its site for which construction is complete 
prior to the effective date of a final rule must comply with the 
conditions and limitations therein including, at a minimum, marking 
requirements for newly constructed or altered meteorological towers 
with the highest point of the structure at least 50 feet AGL up to and 
including 200 feet AGL at its site. Those conditions and limitations as 
they relate to marking will be derived from the current version of AC 
70/7460-1. Existing meteorological towers at least 50 feet AGL and up 
to and including 200 feet AGL are required to file notice with the FAA 
within 90 days of the effective date of a final rule. The FAA will 
study these notices, and the FAA may issue a part 77 determination.
    The primary costs of the proposed rule to industry would be the 
costs to mark new and altered meteorological towers. The estimated 
costs to mark each new or altered tower is about $14,300 and includes 
equipment costs for marker balls and sleeves and installing them to new 
and altered towers, buying a new pre-painted tower, and dismantling a 
tower. This estimated cost also includes the cost to provide FAA 
notifications of both existing and dismantling of out-of-service 
meteorological towers. The FAA would process notifications of existing 
and new meteorological towers, including notifications of dismantled 
out-of-service meteorological towers, at a cost of about $41 per 
existing notification and about $162 per dismantling notification. The 
FAA is also proposing to extend the expiration date of the 
Determination of No Hazard to Air Navigation for permanent wind energy 
systems and associated meteorological towers. Extending the wind 
turbine determination period from 18 months to 36 months would result 
in minimal cost savings to industry and the FAA.
    The primary benefit of the proposed rule would be enhanced 
conspicuity to prevent agricultural pilots from colliding with 
meteorological towers with the highest point of the structure

[[Page 90630]]

at least 50 feet AGL up to and including 200 feet AGL at its site.

II. Authority for This Proposed Rulemaking

    The FAA's authority to issue rules on aviation safety is found in 
title 49 of the United States Code (49 U.S.C.). Subtitle I, section 106 
describes the authority of the FAA Administrator. Subtitle VII, 
Aviation Programs, describes in more detail the scope of the agency's 
authority.
    This rulemaking is issued under the authority described in 49 
U.S.C. 40103(b), which vests the Administrator with broad authority to 
prescribe regulations to ensure the safety of aircraft and the 
efficient use of airspace, and 49 U.S.C. 44701(a)(5), which requires 
the Administrator to promulgate regulations and minimum standards for 
other practices, methods, and procedures necessary for safety in air 
commerce and national security. This rulemaking is also consistent 
with: (1) the authority in 49 U.S.C. 44718(a), which directs the 
Secretary of Transportation to require a person to give adequate public 
notice of the construction, alteration, establishment, or expansion, or 
the proposed construction, alteration, establishment, or expansion, of 
a structure or sanitary landfill in furtherance of safety in air 
commerce and the efficient use and preservation of the navigable 
airspace and of airport traffic capacity at public-use airports; (2) 
section 44718(b), which requires the Secretary to conduct an 
aeronautical study to decide the extent of any adverse impact on the 
safe and efficient use of the airspace, facilities, or equipment if the 
Secretary decides that constructing or altering a structure may result 
in an obstruction of the navigable airspace or an interference with air 
navigation facilities and equipment or the navigable airspace; and (3) 
section 44718(c), which requires that in carrying out laws related to a 
broadcast application and conducting an aeronautical study related to 
broadcast towers, the FAA Administrator and the FCC shall take action 
necessary to coordinate efficiently the receipt and consideration of, 
and action on, the application and the completion of any associated 
aeronautical study.
    Furthermore, the portions of the proposed rule regarding 
meteorological towers are authorized by section 2110 of the 2016 FESSA, 
as amended by section 576 of the 2018 FAARA and section 355 of the FAA 
Reauthorization Act of 2024 (Pub. L. 118-63), that imposed marking and 
informational requirements on covered towers, including meteorological 
towers. The following proposed amendments to part 77 are within the 
scope of this authority. Publication of this NPRM also satisfies the 
requirement in section 355 of the FAA Reauthorization Act of 2024 \7\ 
that the FAA publish this notice of proposed rulemaking within one year 
of the date of enactment of that Act.
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    \7\ Public Law 118-63, sec. 355 (May 16, 2024).
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III. Background

A. Current Regulations and Practices

    Part 77 contains the regulations governing the safe, efficient use, 
and preservation of the navigable airspace. Sponsors proposing to 
construct or alter a structure that is more than 200 feet AGL must 
provide the FAA notice per Sec.  77.9(a). Sponsors must provide notice 
at least 45 days before the start of construction or alteration or the 
date an application for a construction permit is filed, whichever is 
earlier, per Sec.  77.7(b).
    After receiving notice, the FAA's Obstruction Evaluation Group 
(OEG) conducts an initial review to verify the information provided 
and, if appropriate, enters it into the Obstruction Evaluation/Airport 
Airspace Analysis (OE/AAA) system as a verified proposed structure.
    Currently, the FAA will conduct an aeronautical study when 
requested by the sponsor of any proposed construction or alteration for 
which a notice is submitted, or the FAA determines a study is 
necessary.\8\ As part of this study, the FAA determines whether the 
structure exceeds the heights identified in part 77's obstruction 
standards. A structure exceeding one or more of the heights described 
in the obstruction standards is presumed a hazard to air navigation 
unless an aeronautical study determines otherwise. If the proposed 
structure is a presumed hazard, the FAA sends the sponsor a notice of 
preliminary findings (which previously was called a Notice of Presumed 
Hazard) with 60 days to respond.
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    \8\ 14 CFR 77.27.
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    Upon receipt of the preliminary findings, the sponsor has the 
option to move or lower the proposed structure, request further study 
(which may include a public comment period), terminate the proposal, or 
request a Determination of Hazard. The FAA and the sponsor may also 
discuss hazard mitigation strategies, such as reducing the structure's 
height or adjusting the proposed location, prior to the agency's formal 
determination. Proper mitigation, if appropriate, may result in a 
Determination of No Hazard to Air Navigation that contains conditions 
and limitations (e.g., marking, lighting, or supplemental notice filing 
constraints). Each Determination of No Hazard to Air Navigation issued 
under subpart B of part 77 expires 18 months after the effective date 
of the determination, or on the date the proposed construction or 
alteration is abandoned, whichever is earlier. If the FAA determines 
that a structure does not pose a hazard to air navigation, the FAA will 
recommend marking and lighting in the determination, as appropriate, in 
accordance with the current AC 70/7460-1 to make the structure more 
conspicuous for aircraft operators to see and avoid.
    A sponsor may request a modification from the marking and lighting 
recommendations contained in a determination by submitting FAA Form 
7460-1, Notice of Proposed Construction or Alteration, to the OEG. A 
request received after the FAA has issued its determination containing 
marking and lighting conditions and limitations may require a new 
marking and lighting study and could result in new requirements. If the 
FAA issues a modification from the marking or lighting conditions and 
limitations prior to the implementation of the changes, the sponsor may 
also be required to notify the FCC. Modifications would be based on 
whether or not they impact aviation safety.
    A sponsor may also request a deviation from the marking and 
lighting conditions and limitations contained in the determination 
derived from the standards in AC 70/7460-1. Proposed requests to 
deviate from current marking and lighting conditions and limitations 
derived from the standards in AC 70/7460-1 for research and development 
to introduce new technology or improve current standards are generally 
submitted by email. The FAA will perform a safety assessment for use in 
the NAS and may request additional information if needed. If at any 
time the FAA determines the study has created an unsafe condition, the 
deviation request may be disapproved. Research and development testing 
is independent of the aeronautical study process and generally requires 
a more lengthy analysis period for evaluation by the FAA for aviation 
safety. When testing is complete and the FAA concludes its review, the 
sponsor will be notified of the determination. Examples of deviations 
that may be considered include, but are not limited to, alternative 
painting schemes, colors/types of lights, basic signals and intensity 
of lights, night/day lighting combinations, and flash rate.

[[Page 90631]]

B. NTSB Investigations of Meteorological Tower Accidents

    The NTSB is an independent U.S. government agency responsible for 
the investigation of civil transportation accidents.\9\ Between 2003 
and 2011, the NTSB investigated 3 accidents involving meteorological 
towers below 200 feet AGL. A summary of the investigated accidents 
follows:
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    \9\ See NTSB's Aviation Accidents Database at https://data.ntsb.gov/carol-main-public/basic-search.
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     December 15, 2003: During a personal flight from Yakima, 
Washington, to Walla Walla, Washington, an Erickson SHA Glasair 
collided with an unmarked meteorological tower (164 feet AGL) near 
Vansycle, Oregon. The accident resulted in fatalities to the pilot and 
passenger.\10\
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    \10\ NTSB accident number SEA04LA027.
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     May 19, 2005: During an aerial application flight, an Air 
Tractor AT-602 collided with an unmarked meteorological tower (197 feet 
AGL) erected 15 days before the accident near Ralls, Texas. The 
accident resulted in a pilot fatality.\11\
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    \11\ NTSB accident number DFW05LA126.
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     January 10, 2011: During an aerial application flight, a 
Rockwell International S-2R collided with an unmarked meteorological 
tower (198 feet AGL) near Oakley, California. The accident resulted in 
a pilot fatality.\12\
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    \12\ NTSB accident number WPR11LA094.
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    In 2011, the NTSB issued Safety Alert (SA) 016.\13\ The SA warned 
operators that ``unmarked towers could interfere with low-flying 
aircraft operations, including those involving helicopter emergency 
medical services, law enforcement, animal damage control, fish and 
wildlife, agriculture, and aerial fire suppression.'' In 2013, the NTSB 
published a Safety Recommendation letter \14\ addressed to the FAA 
Administrator, containing the following 2 recommendations:
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    \13\ NTSB SA-016: The Hazards of Unmarked Towers (March 2011, 
revised September 2018).
    \14\ NTSB Safety Recommendation A-13-16 and A-13-17 (May 2013).
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     A-13-16: Amend part 77 to require that all meteorological 
towers \15\ are registered, marked, and--where feasible--lighted; and,
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    \15\ While the NTSB and others use the terms ``meteorological 
evaluation tower'' or ``MET'', the FAA decided to use the term 
``meteorological tower''. Meteorological tower is interchangeable 
with either.
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     A-13-17: Create and maintain a publicly accessible 
national database for the required registration of all meteorological 
towers.
    In 2014, the NTSB published a Special Investigation Report (SIR) 
concerning the safety of agricultural aircraft operations.\16\ The SIR 
focused, in part, on the impact of meteorological towers and guy wires, 
which are cables designed for the support of towers or other 
structures, on agricultural aircraft operations and reiterated NTSB 
recommendations A-13-16 and A-13-17. The NTSB concluded that in some of 
the accidents, the pilot was not previously aware of, and did not see, 
the obstacle in time to avoid the collision because the obstacle was 
not visually conspicuous. The report noted the multiple attention 
demands for pilots engaged in agricultural operations. For instance, 
pilots must operate the spray application per the instructions of the 
particular applied substance while simultaneously maneuvering the 
aircraft at low altitude. In other cases, the pilot knew about the 
obstacle, having seen it in a previous pass, a survey flight, or during 
a previous close call, but nevertheless misjudged the aircraft's 
distance from, and collided with, the obstacle.
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    \16\ NTSB/SIR-14/01.
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    The NTSB concluded that these accidents show that obstacle 
collision risk management requires a multi-faceted approach. In 
addition to making meteorological towers more visually conspicuous, the 
NTSB suggested pre-flight planning that would allow a pilot to learn of 
any structures in the area of their planned operations to reduce the 
risk of an obstacle collision. Pilots learn of obstacles from many 
sources, including local residents, area maps (both paper and 
electronic) that depict obstacles, and ground surveys. The SIR 
concluded that additional meteorological tower collisions resulting in 
loss of life would occur without requiring registration, marking, and 
the creation of a publicly accessible national meteorological tower 
database.

C. The 2011 Voluntary Meteorological Tower Marking Policy Statement

    On January 5, 2011, in response to concerns from agricultural 
operators over the safety risk of low-flying operations in remote and 
rural areas and a November 16, 2010, meeting with representatives from 
the National Agricultural Aviation Association (NAAA) to discuss 
safety-specific concerns of the aerial application industry, the FAA 
published a proposed policy statement that recommended voluntary 
marking of meteorological towers under 200 feet AGL.\17\
---------------------------------------------------------------------------

    \17\ Marking Meteorological Evaluation Towers Proposed revision 
to Advisory Circular; request for comments, 76 FR 490 (Jan. 5, 
2011).
---------------------------------------------------------------------------

    The FAA published the final policy on June 24, 2011,\18\ and 
included voluntary marking guidance in AC 70/7460-1L.\19\ The FAA 
continues to modify its voluntary marking criteria in AC 70/7460-1.
---------------------------------------------------------------------------

    \18\ Marking Meteorological Evaluation Towers policy statement, 
76 FR 36983 (Jun. 24, 2011).
    \19\ AC 70-7460-1L, effective December 4, 2015.
---------------------------------------------------------------------------

D. State Requirements Related to Marking of Meteorological Towers

    In the absence of a nationwide requirement for marking 
meteorological towers, at least sixteen states adopted meteorological 
tower marking and notice requirements.\20\ As a result of individual 
state requirements, marking and lighting requirements are inconsistent 
across states and may conflict with FAA AC 70/7460-1 marking 
requirements, which Congress mandated the FAA to adopt for marking 
standards.
---------------------------------------------------------------------------

    \20\ As of January 2022, the FAA identified 16 states with 
marking requirements applicable to meteorological towers: 
California, Colorado, Idaho, Kansas, Michigan, Minnesota, 
Mississippi, Missouri, Montana, Nebraska, North Dakota, Oklahoma, 
South Dakota, Texas, Washington, and Wyoming.
---------------------------------------------------------------------------

    For example, Colorado \21\ requires that certain towers over 50 
feet in height be marked and painted or otherwise constructed to be 
visible in clean air during daylight hours from a distance of not less 
than 2,000 feet. Colorado requires towers be painted in equal 
alternating bands of aviation orange and white, beginning with orange 
at the top of the tower. Additionally, Colorado also requires the 
attachment of one marker ball to the top third of each outside guy wire 
and that guy wires have seven-foot-long safety sleeves at each anchor 
point that extend from the anchor point along each guy wire attached to 
the anchor point.
---------------------------------------------------------------------------

    \21\ Colorado Revised Statutes 43-10-117.
---------------------------------------------------------------------------

    Additional states have similar requirements. Wyoming \22\ 
stipulates that any structure that meets the criteria must be marked in 
a manner that makes the tower recognizable in clear air during daylight 
hours from a distance of at least 2,000 feet. South Dakota's law \23\ 
mandates that any meteorological tower of 50 feet or more, including 
the tower, guy wires, and accessory facilities, located outside the 
boundaries of a municipality must be marked, painted, flagged, or 
otherwise constructed to be recognizable in clear air during daylight 
hours. While some similarities exist between these requirements, they 
are not consistent with FAA AC 70/7460-1 and, considering Colorado's

[[Page 90632]]

requirements, are also inconsistent across three shared state lines.
---------------------------------------------------------------------------

    \22\ Wyo. Stat. Ann. Sec.  10-4-305.
    \23\ SDCL Sec.  50-9-13.
---------------------------------------------------------------------------

    In addition to inconsistent marking requirements, state laws for 
filing notice of existing, new, and dismantled meteorological towers 
vary across state lines. Only five states require notice of current 
meteorological towers, only nine require notice of planned construction 
for new meteorological towers, and only six require notice of 
dismantled meteorological towers. The notice requirements directed by 
states are inconsistent with what the FAA proposes to standardize.
    In response to the inconsistent state marking standards, the FAA 
sent the National Association of State Aviation Officials (NASAO) a 
letter in 2011.\24\ The letter reminded the association that the 
Federal Government occupied the entire field of airspace management and 
aviation safety, preempting state and local regulation related to the 
marking and lighting of structures for aviation safety purposes. The 
FAA is vested with plenary authority to regulate the use of the 
airspace as necessary to ensure the safety of aircraft and the 
efficient use of airspace.\25\
---------------------------------------------------------------------------

    \24\ FAA letter to NASAO (October 27, 2011).
    \25\ 49 U.S.C. 40103(b) and 44718.
---------------------------------------------------------------------------

E. Statutory Mandates

    Section 2110 of FESSA, revised by section 576 of FAARA, requires 
either the marking of covered towers as defined in section 2110, which 
includes meteorological towers, consistent with AC 70/7460-1L or their 
inclusion within a database, except for meteorological towers. Section 
2110 requires all meteorological towers be marked and included in a 
database. Congress also mandated that the database conform to 
additional provisions to ensure data security and accuracy.
    Section 355 of the FAA Reauthorization Act of 2024 requires that 
the FAA publish an NPRM within one year of the date of enactment of the 
2024 Act.

F. Industry Engagement

    The NAAA expressed concerns to the FAA regarding the visibility of 
meteorological towers less than 200 feet AGL not currently subject to 
notice requirements, stating that these towers are particularly 
hazardous to pilots of low-flying aircraft in remote and rural 
areas.\26\ The NAAA referenced its 2019 survey \27\ and reported that 
agricultural operators and pilots considered power lines, communication 
towers, and meteorological towers as the top three occupational 
hazards. Additionally, 52 percent of the respondents encountered a wind 
turbine or an unmarked meteorological tower when making aerial 
applications.
---------------------------------------------------------------------------

    \26\ NAAA Fact Sheet on the Dangerous Effects of Towers to Low-
Level Aviators (January 2020) and NAAA Facts About the Aerial 
Application Industry (available at https://www.agaviation.org/industryfacts).
    \27\ Per NAAA, 550 operators and 305 pilots responded to the 
survey, available at www.agaviation.org.
---------------------------------------------------------------------------

    The NAAA continues to urge the FAA to expand tower marking guidance 
to include all guy wire and freestanding towers more than 50 feet in 
height. Further, NAAA asked the FAA to require tower marking and 
lighting, if feasible.

G. The 2022 Airborne Wind Energy Systems Policy Statement

    As noted previously, on December 7, 2011, the FAA published the 
Notification for Airborne Wind Energy Systems (AWES) notice of policy 
and request for information in the Federal Register.\28\ The 2011 
notice established policy related to airborne wind energy systems. The 
2011 notice also stated that given the altitudes in which airborne wind 
energy systems can operate and their operating characteristics, the FAA 
concluded that they should be studied and the potential impacts to the 
navigable airspace must be identified and addressed.
---------------------------------------------------------------------------

    \28\ Notification for Airborne Wind Energy Systems (AWES) notice 
of policy and request for information, 76 FR 76333 (Dec. 7, 2011).
---------------------------------------------------------------------------

    Accordingly, in the 2011 notice the FAA announced that the 
provision of part 77 will apply to temporary airborne wind energy 
systems proposals for data collection purposes. At that time, the FAA 
found that it could apply the provisions of 14 CFR part 77 to these 
``structures'' without the need to amend the regulations. The FAA 
stated that permanent and operational airborne wind energy systems may 
be addressed in the future, once further evaluations and risk 
assessments are performed.
    To facilitate the timely manner in which airborne wind energy 
systems proposals were reviewed, the FAA, in the 2011 proposal, 
requested airborne wind energy systems developers and operators to 
limit temporary operations to the following:
    (1) Airborne operations of airborne wind energy systems should be 
temporary in nature for testing and data collection purposes only;
    (2) Single airborne wind energy system devices only (e.g., no 
``farms'' or multiple simultaneous testing);
    (3) Airborne wind energy systems should be limited to a single 
fixed location (e.g., no mobile ground facilities);
    (4) Testing is confined to heights at or below 499 feet AGL;
    (5) Airborne flight testing of airborne wind energy systems will 
only occur during daylight hours; and,
    (6) Airborne wind energy systems will be made conspicuous to the 
flying public.
    The FAA sought comments on revising its policy regarding the 
application of 14 CFR part 77 to airborne wind energy systems. In 
addition, the notice requested information from airborne wind energy 
system developers and the public related to these systems so that the 
FAA could comprehensively analyze the airborne wind energy systems and 
their integration into the NAS.
    On December 23, 2022, the FAA published the Airborne Wind Energy 
(AWES) Policy Statement in the Federal Register in response to the 2011 
statement.\29\ The 2022 policy summarized and discussed the comments 
received in response to the 2011 notice. In the 2022 policy statement, 
the FAA amended the policy set forth in the 2011 notice and stated it 
will consider part 77 applications for all airborne wind energy 
systems, including permanent and operational systems. Those entities 
proposing construction of an AWES that exceeds the parameters in Sec.  
77.9 (e.g., an airborne wind energy system constructed at more than 200 
feet AGL at its site) must file advance notice with the FAA.
---------------------------------------------------------------------------

    \29\ Airborne wind Energy System (AWES) Policy Statement, 87 FR 
78849 (Dec. 23, 2022).
---------------------------------------------------------------------------

III. The Proposed Rule

A. Requirements Related to Meteorological Towers

1. Definition of Meteorological Tower (Sec.  77.3)
    The FAA proposes to define a meteorological tower in Sec.  77.3 as 
``a skeletal or pole-type structure, either freestanding or anchored 
with guy wires, configured with components to measure wind speed and 
wind direction at different heights above ground level to assess local 
wind energy resources.'' The proposed definition incorporates skeletal 
or pole-type structures, common elements of meteorological towers. 
There are single tower masts, self-supporting antenna towers, guyed 
telescopic towers, or telescopic un-guyed towers that can rapidly 
deploy to heights more than 100 feet AGL. There are also stand-alone 
towers that do not

[[Page 90633]]

use guy wires, all of which are covered by this definition.
    The definition encompasses permanent and temporary meteorological 
towers, freestanding meteorological towers, and meteorological towers 
with guy wires due to the see and avoid safety risks they each pose. 
Under this proposed definition, the FAA would identify where these 
towers are located, publish the locations in a database, and have them 
marked where appropriate in an effort to increase safety at lower 
altitudes. Temporary towers can be erected in a matter of hours, 
creating an unexpected safety risk for pilots, even for those familiar 
with the area. The FAA is including meteorological towers with guy 
wires, which are freestanding structures with a tensioned cable 
designed to add stability because, depending upon the materials used, 
the guy wires may be difficult to see in certain atmospheric 
conditions.
2. Notice Requirements for Proposed or Altered Meteorological Towers 
With the Highest Point of the Structure at Least 50 Feet AGL Up to and 
Including 200 Feet AGL at Its Site (Sec. Sec.  77.7, 77.9(a)(2))
    Consistent with current practice, the FAA would require a sponsor 
of a meteorological tower with the highest point of the structure at 
least 50 feet AGL up to and including 200 feet AGL at its site to file 
notice pursuant to Sec.  77.7 before the start of construction or 
alteration or the date of application for a construction permit for any 
new meteorological tower, whichever is earlier.\30\ Specifically, the 
sponsor would be required to electronically complete and submit FAA 
Form 7460-1, Notice of Proposed Construction or Alteration, or FAA Form 
7460-2, Notice of Actual Construction or Alteration, via the internet 
at https://oeaaa.faa.gov. Except under limited circumstances, a sponsor 
required to provide notice would be required to submit FAA Form 7460-1 
at least 45 days before the start date of the proposed construction or 
alteration, or the date an application for a construction permit is 
filed, whichever is earlier.
---------------------------------------------------------------------------

    \30\ Sec.  77.7(a) and (b).
---------------------------------------------------------------------------

    The FAA proposes to add a new paragraph (a)(2) to Sec.  77.9 to 
require notice of the construction or alteration of meteorological 
towers with the highest point of the structure at least 50 feet AGL up 
to and including 200 feet AGL at its site in order to allow for the 
tower's inclusion within the FAA's publicly available database; 
additional study of the structure pursuant to part 77; and the marking 
of those towers.
    The FAA would also add a new Sec.  77.5(d) to make clear that a 
sponsor proposing any construction or alteration of a meteorological 
tower with the highest point of the structure at least 50 feet AGL up 
to and including 200 feet AGL at its site must provide adequate notice 
to the FAA of that construction or alteration pursuant to Sec.  
77.7(b).
    If the FAA does not receive a notice, it cannot study the structure 
or include it in the FAA's public (DOF) database.\31\ If the FAA does 
not include in its DOF database a meteorological tower with the highest 
point of the structure at least 50 feet AGL up to and including 200 
feet AGL at its site, operators of low-flying aircraft, including 
agricultural operators or first responders, may not be aware of the 
locations of the same. This proposal would direct sponsors to file 
notice and provide detailed information concerning meteorological 
towers with the highest point of the structure at least 50 feet AGL up 
to and including 200 feet AGL at its site. Filing notice would enable 
the FAA to provide this information to the public via a publicly 
available database. Pilots of agricultural and other low-flying 
aircraft operators (e.g., emergency medical services aircraft, 
firefighting aircraft, utility patrol and maintenance aircraft, fish 
and wildlife service aircraft, aerial survey aircraft, and military 
aircraft) would have the ability to obtain this information for 
preflight planning purposes pursuant to Sec.  91.103, which requires 
each pilot in command to become familiar with all available information 
concerning that flight.
---------------------------------------------------------------------------

    \31\ The FAA may include some structures or obstacles on 
aeronautical charts. In cases where a structure is charted and noted 
in the FAA database, pilots are responsible for entering the 
relevant location information in their navigation system. Although 
Global Positioning System (GPS) equipment is not required by the FAA 
for visual flight rules (VFR) flight, the FAA believes that most 
agricultural operators equipped their aircraft with GPS, based on a 
2019 NAAA industry survey. This survey also showed that 99% of 
respondents reported that they use a GPS device for swath guidance. 
A GPS display can also show the pilot the aircraft's location when 
the spray was turned on or off and can enable the marking of 
boundaries, obstacles, and other user-defined inputs.
---------------------------------------------------------------------------

    While markings are critical features that assist pilots of low-
flying aircraft to see obstacles in their flightpath, the FAA concludes 
it is crucial to provide a database of known obstacles for pilots to 
use during flight planning to increase pilots' situational awareness. 
Given the number of competing elements for pilot attention during low-
altitude flight, whether during routine operations or when experiencing 
an in-flight anomaly or emergency with limited time to respond safely, 
a database providing the accurate locations of meteorological towers 
with the highest point of the structure at least 50 feet AGL up to and 
including 200 feet AGL at its site may reduce the risk of collision 
accidents to low-flying aircraft. To include meteorological towers in 
the database for public and pilot awareness, sponsors must file notice 
with the FAA. Therefore, the FAA determined it is appropriate to 
propose to amend the current provisions of part 77 to require all 
sponsors of newly constructed and altered meteorological towers with 
the highest point of the structure at least 50 feet AGL up to and 
including 200 feet AGL at its site to file advance notice with the FAA 
on a mandatory basis.
    Expanding the existing notice requirement to include existing 
meteorological towers with the highest point of the structure at least 
50 feet AGL up to and including 200 feet AGL at its site would also 
enable the FAA to conduct an aeronautical study. The FAA may issue a 
part 77 determination. If the FAA issues a determination, pursuant to 
Sec.  77.12, the FAA would only issue recommended conditions and 
limitations.
    The FAA is proposing notice of meteorological towers with the 
highest point of the structure at least 50 feet AGL up to and including 
200 feet AGL at its site. The FAA considered proposing to require 
notice of a meteorological tower at any height but determined that such 
a proposal would be unnecessarily broad based on accident data specific 
to meteorological towers. The FAA excluded towers under 50 feet AGL 
from this rulemaking as the risk of inadvertent collision is minimal 
due to the low number of operations that occur at those altitudes. 
Outside of takeoff and landing as well as crop dusting, few operations 
occur below 50 feet AGL. Finally, from the data provided by the NTSB, 
none of the accidents they investigated occurred below 50 feet AGL.
3. Notice Requirements for Existing Meteorological Towers Constructed 
With the Highest Point of the Structure at Least 50 Feet AGL Up to and 
Including 200 Feet AGL at Its Site (Sec. Sec.  77.7(d) and 77.9(b))
    Existing meteorological towers with a height at or below 200 feet 
AGL generally do not meet notice criteria in Sec.  77.9 unless they 
exceed an imaginary surface or are constructed on an airport under 
current Sec.  77.9(b) and (d).\32\ The

[[Page 90634]]

FAA proposes amending Sec.  77.7 by adding paragraph (d) and adding 
Sec.  77.9(b), requiring sponsors of existing meteorological towers 
with the highest point of the structure at least 50 feet AGL up to and 
including 200 feet AGL at its site to file notice with the FAA within 
90 days of the effective date of a final rule. As proposed in Sec.  
77.7(d), sponsors would be required to complete and submit notice of 
existing towers electronically via the internet at https://oeaaa.faa.gov using FAA Form 7460-1.
---------------------------------------------------------------------------

    \32\ Some sponsors of meteorological towers with a height less 
than 200 feet AGL submitted voluntary notifications to the FAA. 
Because these structures do not meet or exceed the current 
notification requirements in part 77, the FAA issued a Determination 
of No Hazard without any marking and/or lighting conditions. 
However, the FAA encourages sponsors to voluntarily comply with 
marking and lighting standards in FAA AC 70/7460-1.
---------------------------------------------------------------------------

    The FAA intends to require the sponsors of any existing 
meteorological tower, whether in use or not but still standing, to 
provide the FAA notice of its existence. The FAA determined that 
existing meteorological towers at the same heights will continue to 
pose an undue risk to low-flying aircraft unless sponsors file notice 
with the FAA or dismantle the tower. Upon receiving a notice as 
proposed, the FAA would create a public record of the meteorological 
tower in the DOF database, detailing the tower's location, height, and 
marking or lighting. This database inclusion would ensure availability 
of the most current information available for pilots to use in 
preflight planning.
    The FAA considers 90 days as a reasonable time for industry to file 
notice of existing meteorological towers because it will allow for 
sponsors to dismantle any temporary towers and for the sponsors to 
gather information. The purpose of requiring existing towers to file is 
to ensure inclusion of these towers in the FAA's publicly available 
database as soon as practicable.
    The proposed amendment would also subject existing meteorological 
towers to the provisions in subparts C and D of part 77, such as the 
requirement to notify the FAA when the structure is abandoned or 
dismantled in accordance with current Sec.  77.11 (proposed Sec.  
77.10). Including these subparts would ensure the FAA's ability to 
remove the structure from its database when supplemental notice is 
received by the FAA, thereby increasing the accuracy of information 
provided to the public.
    The FAA also proposes to revise Sec.  77.5(e) to make clear that 
the FAA would use the notice provided by a sponsor to evaluate the 
effect of a meteorological tower in existence before the effective date 
of a final rule on safety in air commerce and the efficient use and 
preservation of the navigable airspace and of airport traffic capacity 
at public use airports. The notice would also be used by the FAA to 
determine whether the effect of a meteorological tower in existence 
before the effective date of a final rule is a hazard to air 
navigation. The FAA will study these notices, and the FAA may issue a 
part 77 determination. If the FAA issues a determination, pursuant to 
Sec.  77.12, the FAA would only issue recommended conditions and 
limitations.
    Amending part 77 to require notice from sponsors of existing 
meteorological towers constructed at least 50 feet AGL up to and 
including 200 feet AGL at their sites, regardless of location, would 
reduce the potential collision risk with unmarked meteorological towers 
or their guy wires for pilots of low-flying VFR aircraft. If the FAA 
adopts the proposed amendment, a pilot or operator would be able to 
search the FAA's public database, access meteorological tower pertinent 
information for preflight planning purposes, and input the information 
into their GPS system (if equipped) to provide additional situational 
awareness of the tower while airborne.
    With this data, agricultural and other low-flying aircraft 
operators could better manage the risk associated with potential 
obstacle collisions by exercising pre-flight planning procedures. For 
that reason, it is particularly important that pilots engaged in low-
flying aircraft operations routinely check the FAA's public DOF 
database for use during pre-flight planning to confirm existing 
structures or identify new structures where they plan to operate. The 
FAA urges pilots to use GPS systems to track all obstructions contained 
in the database. Similarly, the FAA recommends that pilots incorporate 
obstacle analysis tasks into preflight planning to identify obstacles 
before conducting survey flights of the area. In fact, the NTSB noted 
that ``pilots involved in collision accidents in 2013 reported that 
they performed survey flights but did not see the obstacles that the 
aircraft eventually hit.'' \33\
---------------------------------------------------------------------------

    \33\ NTSB/SIR-14/01.
---------------------------------------------------------------------------

B. Partial Implementation of the FESSA

1. Meteorological Towers
    The FAA proposes to partially implement section 2110 of FESSA, as 
amended by section 576 of FAARA of 2018. Section 2110 requires the FAA 
to have all ``covered towers'' marked consistent with applicable 
guidance in the advisory circular of the FAA issued December 4, 2015 
(AC 70/7460-IL) or entered into a database (meteorological towers must 
be marked and entered into a database). Congress defined a covered 
tower as a meteorological tower, self-standing tower, or tower 
supported by guy wires and ground anchors with the highest point of the 
structure at least 50 feet AGL up to and including 200 feet AGL at its 
site that meet certain criteria. The FAA is not proposing to require 
all self-standing towers or all towers supported by guy wires and 
ground anchors with the highest point of the structure at least 50 feet 
AGL up to and including 200 feet AGL at its site to be marked or be 
included in a database. The data from the NTSB show that very few 
accidents involve self-standing towers or towers supported by wires and 
ground anchors with the highest point of the structure at least 50 feet 
AGL up to and including 200 feet AGL at its site that do not also 
involve a meteorological tower or a tower that supports electric 
utility transmission or distribution lines, the latter of which section 
2110 excludes. Due to the minimal number of accidents involving towers 
not excluded by section 2110, the FAA is proposing to limit the tower 
marking and database requirements to meteorological towers.
    Section 2110 sets forth criteria that narrows which towers are 
considered covered towers. Specifically, Congress stated that a tower 
should be captured if it meets the following:
     Is 10 feet or less in diameter at the above ground base, 
excluding concrete footing;
     Has accessory facilities on which an antenna, sensor, 
camera, meteorological instrument, or other equipment is mounted; and,
     Is located on land that is in a rural area and used for 
agricultural purposes or immediately adjacent to such land.
    The FAA captures these towers but, because the NTSB data 
demonstrated the majority of the incidents involved meteorological 
towers regardless of equipment, diameter, or location, expanded its 
definition to include meteorological towers of all sizes, equipage, and 
location.
    Section 2110 also sets forth those towers that are not considered 
covered towers. NTSB data demonstrated that the majority of the 
incidents involved meteorological towers regardless of equipment, 
diameter, or location. As such, in order to improve safety, the FAA is 
not proposing to adopt the following exclusions:
     Is adjacent to a house, barn, electric utility station, or 
other building;
     Is within the curtilage of a farmstead or adjacent to 
another building or visible structure; or,

[[Page 90635]]

     Is located within the right-of-way of a rail carrier, 
including within the boundaries of a rail yard, and is used for a 
railroad purpose.
    The FAA is also proposing to not include the following exclusion 
for towers:
     Has already mitigated any hazard to aviation safety in 
accordance with FAA guidance or as otherwise approved by the FAA 
Administrator.
    Congress mandated that meteorological towers be entered into a 
database as well as marked. As supported by NTSB data, the entry into a 
database via notice to the FAA would ensure aircraft operators are 
aware in advance of the location of the towers. As such, the FAA is not 
proposing to exclude these towers if they are independently marked or 
if the FAA receives notice of a tower to enable inclusion within the 
FAA's database. Moreover, the FAA wants the opportunity to study each 
tower and to assess the proper marking and potential lighting 
requirements. The FAA also wants to be kept abreast of any changes. 
Without covering these meteorological towers, the FAA will not be able 
to make an independent assessment about what terms and conditions 
should apply to ensure safety and the sponsor would not be subject to 
the ongoing obligations to update the FAA.
    This proposal also would not implement section 2110's requirement 
that sponsors mark meteorological towers that exist at the time of the 
final rule's effective date. The FAA would require that sponsors of 
existing meteorological towers file notice with the FAA within 90 days 
of the effective date of a final rule using FAA Form 7460-1. These 
notices would enable the FAA to study those towers. Existing 
meteorological towers at least 50 feet AGL up to and including 200 feet 
AGL are required to file notice with the FAA within 90 days of the 
effective date of a final rule. The FAA will study these notices, and 
the FAA may issue a part 77 determination. If the FAA issues a 
determination, pursuant to Sec.  77.12, the FAA would only issue 
recommended conditions and limitations. If a sponsor alters an existing 
tower, the FAA proposes to then impose marking requirements. The FAA is 
not proposing to impose retroactive marking requirements as existing 
towers would already be in the DOF to alert aircraft operators of their 
presence, sponsors will have marking recommendations, and sponsors will 
be required to mark a tower if the tower is altered or file notice when 
dismantling a tower so the FAA may remove it from the DOF database. 
Finally, in the interest of safety, the FAA is not including section 
2110's exclusion and waiver provisions in this proposal due to the need 
for all meteorological towers at least 50 feet AGL up to and including 
200 feet AGL at their sites to be studied and added to the DOF.
    The FAA proposes to implement only those provisions of section 2110 
applicable to meteorological towers supported by safety data and 
aviation accidents involving meteorological towers with the highest 
point of the structure below 201 feet AGL. However, this limitation 
does not address the risk to the larger population of low-flying 
aircraft operators identified by NTSB that the FAA seeks to mitigate 
with this proposal, including the risk to helicopter emergency medical 
services, law enforcement, animal damage control, fish and wildlife 
surveys, and aerial fire suppression.\34\ The FAA agrees with NTSB that 
the demonstrated risk to low-flying aviation, as a whole, posed by 
unmarked meteorological towers justifies requiring notice of 
meteorological towers regardless of location.\35\ The proposal also 
partially addresses NTSB's 2013 safety recommendations A-13-16 and A-
13-17, issued in 2013. In sum, it would provide the FAA with 
information that will improve the safety of low-flying aircraft.
---------------------------------------------------------------------------

    \34\ https://www.ntsb.gov/safety/safety-recs/RecLetters/A-13-016-017.pdf.
    \35\ NTSB accident number SEA04LA027 (December 15, 2003): 
Accident when an aircraft operating for personal flight collided 
with an unmarked meteorological tower (164 feet AGL).
---------------------------------------------------------------------------

    Newly filed proposed and altered meteorological towers with the 
highest point of the structure at least 50 feet AGL up to and including 
200 feet AGL at their sites would be subject to the marking 
requirement. Meteorological towers can come from the manufacturer 
painted, reducing the burden of painting the structure after delivery. 
Dismantling an existing tower to paint it would be costly, considering 
the average deployment of one to three years. Regardless of marking, 
the existing towers would be included in the database.
2. Database
    The FAA plans to partially implement section 2110's database 
requirement without making regulatory changes beyond those already 
discussed. Section 2110 requires the FAA to develop or utilize an 
existing database that contains the location and height of covered 
towers and to keep the database current to the extent practicable. The 
agency also must ensure that any proprietary information in the 
database is protected from disclosure in accordance with law. In 
addition, the FAA Administrator must ensure that, by virtue of 
accessing the database, users agree and acknowledge that information in 
the database may only be used for aviation safety purposes and may not 
be disclosed for purposes other than aviation safety, regardless of 
whether or not the information is marked or labeled as proprietary or 
with a similar designation. Further, the section directs the FAA to 
ensure that tower information in the database is de-identified and that 
the information only includes the location, height, and presence of guy 
wires. The FAA must ensure the information in the dataset is encrypted 
at rest and in transit and is protected from unauthorized access and 
acquisition. Additionally, the FAA must ensure registration of towers, 
database inclusion of proposed towers before construction, and database 
availability for pilots who intend to conduct low-altitude operations 
so they may consult the database before flight operations. Lastly, 
section 2110 states that the database must be available for use within 
1 year of the effective date of the rule. The FAA plans to use the 
existing OE/AAA system to partially implement section 2110's database 
requirement. The FAA would include any structure filing notice under 
current regulations, those giving notice pursuant to proposed changes 
applicable to meteorological towers with the highest point of the 
structure at least 50 feet AGL up to and including 200 feet AGL at its 
site, and wind turbines in the database.
    The existing OE/AAA system meets section 2110's general intent to 
make information concerning structures that may pose a hazard to 
aviation available to the flying public. The available data includes 
structure type, location, latitude, longitude, height, elevation, 
marking, lighting, and proximity to the nearest town and airport. The 
information available on the OE/AAA website \36\ depicts accurate 
information received from filed notices of proposed structures that 
require issuance of an FAA determination.\37\
---------------------------------------------------------------------------

    \36\ https://oeaaa.faa.gov.
    \37\ The FAA conducts studies on more than 100,000 structures 
annually. However, the database is limited to those structures 
located in close proximity to a public-use airport.
---------------------------------------------------------------------------

    Although pilots can search for known meteorological towers on the 
OE/AAA website without having a user account, any interested party can 
register for, and establish, a user account. Once registered, the 
interested party can subscribe to receive email notifications

[[Page 90636]]

when the FAA receives a request for obstacle construction or 
modification within a geographic area defined by the user. The OE/AAA 
website also provides a tool that allows a user to find all obstacles 
of notice received within a user-defined radius from a location. Source 
information for this tool comes from a combination of the notices of 
proposed construction or alteration submitted to the FAA's Obstruction 
Evaluation Group and the DOF.\38\
---------------------------------------------------------------------------

    \38\ www.faa.gov/air_traffic/flight_info/aeronav/digital_products/dof.
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    Consistent with section 2110, the FAA would update the system to 
include meteorological towers and create an ability to search for known 
meteorological towers via the FAA's public OE/AAA website. This update 
would allow pilots to obtain a list of meteorological towers by 
location (e.g., state) from the FAA's database. As proposed, filers 
would also be required to notify the FAA if the structure is dismantled 
or abandoned \39\ to enable the FAA to update its database. In 
addition, the FAA would add disclaimers to the site consistent with 
section 2110 to reflect the limits on the use of the available 
information for aviation safety purposes, and that the information may 
not be disclosed for purposes other than aviation safety, regardless of 
whether the information is marked or labeled as proprietary or with a 
similar designation. The FAA intends to modify the OE/AAA system to 
coincide with the effective date of the final rule.
---------------------------------------------------------------------------

    \39\ The FAA considers a structure dismantled when it is taken 
down and abandoned when a proposed structure is not built.
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    The FAA would maintain and update the existing OE/AAA system to 
meet the objectives of section 2110. This would fully address NTSB 2013 
safety recommendation A-13-17. Section 2110's requirement to ensure 
pilots conducting low-altitude operations consult the relevant parts of 
the database is outside the scope of this rulemaking and falls under 14 
CFR part 91. The FAA recommends that pilots use the DOF database to 
obtain the most up-to-date information prior to flight.
3. Exclusion and Waiver Authorities
    Section 2110 authorizes the FAA administrator to exclude a class, 
category, or type of tower that is determined to not pose a hazard to 
aviation safety after public notice and comment. It also directs the 
FAA to establish a process to waive specific towers from marking 
requirements if the agency determines the tower does not pose a hazard 
to aviation safety. Section 2110 requires the Administrator to consider 
specific factors that may mitigate risk and to consider excluding 
towers located in a state that has enacted tower marking requirements. 
As explained earlier, the FAA is limiting this proposal to those towers 
for which it has accident data to support the regulation. In this case, 
the proposal applies to meteorological towers with the highest point of 
the structure at least 50 feet AGL up to and including 200 feet AGL at 
its site. Because the agency determined the expanded definition of a 
covered tower would include those that do not pose a hazard to aviation 
safety given the FAA has no accident data involving these structures, 
the FAA would exclude other structures (a self-standing tower or tower 
supported by guy wires and ground anchors) meeting the section 2110 
definition of a covered tower.
    Section 2110 requires the Administrator to consider specific 
factors that may mitigate risk and to consider excluding towers located 
in a state that has enacted tower marking requirements. As explained 
above, the FAA issued a letter reiterating that the Federal Government 
occupies the entire field of airspace management and aviation safety, 
preempting state and local regulation related to the marking and 
lighting of structures for aviation safety purposes. The FAA is vested 
with plenary authority to regulate the use of the airspace as necessary 
to ensure the safety of aircraft and the efficient use of airspace.

C. Wind Energy Systems

1. Definition of Wind Energy System and Airborne Wind Energy System 
(Sec.  77.3)
    The FAA proposes to define a wind energy system in Sec.  77.3 to 
mean ``structures that convert kinetic energy in the wind to electrical 
energy. A wind energy system may consist of a single structure or a 
group of structures.'' This definition is inclusive of all wind energy 
systems (e.g., airborne wind energy systems (AWES) or wind turbines 
generally composed of a horizontal turbine nacelle, mounted on a fixed 
vertical structure or tower or AWES). This definition would provide 
additional clarity and context for the proposed changes directed 
exclusively at wind energy systems.
    Further, the FAA proposes to define ``airborne wind energy system 
(AWES)'' in Sec.  77.3, consistent with the FAA's 2022 final notice of 
policy.\40\ AWES would mean a structure, which consists of a self-
supported airborne system tethered to a ground station, with an 
airborne or ground-mounted drivetrain used to convert kinetic energy in 
the wind to mechanical power for the purpose of generating electricity.
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    \40\ Airborne Wind Energy Systems (AWES) Policy Statement, 87 FR 
78849 (Dec. 23, 2022).
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2. Proposal for 90-Day Advance Notice of Construction or Alteration of 
Wind Energy Systems (Sec.  77.7(c))
    Currently, a sponsor must submit notice 45 days before the start 
date of the proposed construction or alteration, or the date an 
application for a construction permit is filed, whichever is earlier. 
The FAA proposes to add Sec.  77.7(c) requiring sponsors to submit 
notice of the proposed construction or alteration of a wind energy 
system with a proposed height greater than 200 feet AGL at least 90 
days before the start date of the proposed construction or alteration, 
or the date an application for construction or alteration permit is 
filed, whichever is earlier. The FAA would redesignate the provisions 
currently codified in Sec. Sec.  77.7(c) and (d) as Sec. Sec.  
77.7(b)(1) and (2), respectively. As part of this proposal, the FAA 
would clarify that a meteorological tower is associated with a wind 
energy system when it is included in a wind energy systems project and 
is intended to be permanent. A meteorological tower is permanent when 
it is intended to remain in place for the duration of its lifecycle.
    Due to the unique physical characteristics of wind energy systems, 
specifically wind turbine structures, their potential impact to 
communication, air navigation, and surveillance systems as well as the 
increasing number of proposals requiring an aeronautical study, the FAA 
requires additional time to conduct studies of wind turbines and 
determine potential NAS impacts. This proposal would realistically 
represent the time it currently takes the FAA to study these complex 
structures. Provided with a more realistic representation of the 
obstruction evaluation processes duration, sponsors can better plan 
their projects.
    Wind energy system proposals are significantly more complex than 
other traditional structures, such as buildings, and more frequently 
require an in-depth study to analyze their potential effects on air 
navigation facilities and equipment. The FAA OE/AAA metrics confirm the 
duration of aeronautical studies for proposed wind turbines exceeds 
those for other structure types due to air traffic, communication, air 
navigation, and surveillance (e.g., radar) considerations. While the 
FAA has made considerable progress in identifying mitigation solutions

[[Page 90637]]

required to issue a Determination of No Hazard to Air Navigation for 
proposed wind turbines, the current 45-day notice requirement in Sec.  
77.7(b) does not allow the FAA adequate time to gather the data and 
model potential impacts of proposed wind turbine(s) on NAS air 
navigation facilities and equipment. Additionally, 45 days does not 
adequately represent the time required to work with the sponsor and 
identify mitigations necessary to complete the study.
    The number of new wind turbine proposals processed by the FAA has 
increased substantially since the enactment of the Energy Policy Act of 
2005 \41\ that provided the Wind Energy Production Tax Credit to 
stimulate investment in wind energy. In 2004, the FAA received and 
conducted 3,030 wind turbine aeronautical studies. Since then, the FAA 
received an average of 21,148 wind turbine cases per year, with the 
highest being 33,396 cases in 2010. According to the Department of 
Energy's (DOE) 2015 Wind Vision Report,\42\ which expands upon its 2008 
report titled 20% Wind Energy by 2030,\43\ DOE continues to target wind 
energy as contributing to 20 percent of the U.S. electrical supply by 
2030, compared to more than 4.5 percent at the time of publication. Per 
DOE data, wind electricity generation accounts for 8.4 percent of the 
total U.S. generation as of 2020.\44\ Hence, the FAA expects the demand 
to evaluate proposed construction and altered wind energy systems will 
continue and may increase.
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    \41\ Public Law 109-58, 119 Stat. 594 (Aug. 8, 2005).
    \42\ https://www.energy.gov/eere/wind/wind-vision.
    \43\ https://www.energy.gov/eere/wind/20-wind-energy-2030-increasing-wind-energys-contribution-us-electricity-supply.
    \44\ https://www.eia.gov/energyexplained/wind/electricity-generation-from-wind.php.
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    Furthermore, the proposed timeline would allow the FAA to request 
additional information from sponsors as needed for review per the 
proposed Sec.  77.11 language. While sponsors of proposed wind turbines 
would provide earlier notification prior to construction or alteration, 
the FAA expects that the total time for review would remain the same as 
it does today. The benefits from potentially reducing any delays in 
construction would likely offset any costs associated with the sponsor 
providing earlier notification. The FAA also proposes to amend current 
Sec.  77.7(c) (proposed to be redesignated as Sec.  77.7(e)) by 
clarifying that the 90-day advance notice requirement applicable to 
wind turbines is also eligible for a waiver because of an emergency 
involving essential public services, public health, or public safety.
3. Proposal for Extended Effectiveness Period for Wind Turbine 
Determinations (Sec.  77.33(c))
    The FAA proposes to amend Sec.  77.33 by extending the effective 
period for a Determination of No Hazard involving wind turbines and any 
associated meteorological tower from 18 to 36 months. The FAA would 
redesignate the provision currently codified in Sec.  77.33(c) as Sec.  
77.33(d).
    Wind energy systems developers often file notice with the FAA years 
before their target date to begin construction. They file early to 
allow time to address environmental and other local land-use 
requirements, secure financing, acquire materials, and complete tests 
at proposed locations using meteorological towers to validate the 
potential benefits of a particular location. As a result, wind turbine 
project developers routinely ask the FAA for a one-time 18-month 
extension of the Determination of No Hazard to Air Navigation in 
accordance with the FAA regulations pursuant to Sec.  77.35(c). 
However, even with an 18-month extension, the project may not be built 
within that 3-year period, causing the developer to refile notice with 
the FAA, essentially starting the process again. Extending the wind 
turbine determination period from 18 to 36 months would allow industry 
additional time to validate and begin projects.
    Under the current Sec.  77.33(b), each Determination of No Hazard 
to Air Navigation issued under part 77 expires 18 months after the 
effective date of the determination, unless extended, revised, or 
terminated. Due to the increasing size of individual wind turbines and 
the number of wind turbines needed to accomplish renewable energy 
goals, the duration to construct wind turbine farms can take 
considerably more time to construct than single structures. The 18-
month effectiveness period is frequently insufficient to allow the 
sponsor enough time to complete construction, even with a one-time 
extension. In alignment with proposing to extend wind turbine 
determination periods, the FAA also proposes to extend determination 
periods for meteorological towers associated with a wind energy system 
project from 18 to 36 months. A meteorological tower is associated with 
a wind energy system when it is included in a wind energy systems 
project and is intended to be permanent. A meteorological tower is 
permanent when it is intended to remain in place for the duration of 
its lifecycle.

D. Other Clarifications Related to the Filing of Notice (Sec. Sec.  
77.10, 77.11, 77.27)

    The FAA proposes to redesignate Sec.  77.11 as Sec.  77.10 and 
amend it to identify the form, FAA Form 7460-2, Notice of Actual 
Construction or Alteration, sponsors currently use to provide 
supplemental notice. The revision also makes clear that a sponsor must 
file supplemental notice if otherwise requested by the FAA.
    The FAA proposes to add a new Sec.  77.11 to affirmatively require 
that if the FAA requests additional information during any part of the 
aeronautical study process, pre- or post- determination, the sponsor 
must provide that information within 30 days. The FAA needs this 
information to conduct complete aeronautical studies and issue accurate 
determinations.
    The FAA proposes to revise Sec.  77.27 to clarify when the FAA 
would conduct an aeronautical study. Specifically, the FAA will conduct 
an aeronautical study when: (1) notice required under Sec.  77.9 has 
been received, or (2) the FAA determines a study is necessary. All 
other notices filed by the public outside of these parameters, meaning 
notice is neither requested by the FAA nor required under Sec.  77.9, 
will be screened within the automated OE/AAA system and, if 
appropriate, provided an electronic letter response that indicates that 
no notice is required for the said proposal or alteration, and thus the 
FAA has no objections to the proposal at this time. This process would 
reduce the workload burden on the FAA and still provide the public with 
documentation for local and state requirements at an accelerated rate.

E. General Changes

    The FAA proposes to add Sec.  77.12 to formalize the FAA's 
requirement for sponsors of structures, except for structures that have 
received an FAA Determination of No Hazard to Air Navigation prior to 
the effective date of a final rule or any meteorological tower with the 
highest point of the structure at least 50 feet AGL up to and including 
200 feet AGL at its site for which construction is complete prior to 
the effective date of a final rule, to comply with the conditions and 
limitations contained in a Determination of No Hazard to Air 
Navigation. The FAA provides conditions and limitations, including 
marking, in its determinations. Currently, the FAA recommends that 
sponsors conform with the standards in the AC 70/7460-1. In this 
rulemaking, the FAA is clarifying that the conditions and

[[Page 90638]]

limitations themselves are mandatory except for structures that have 
received an FAA Determination of No Hazard to Air Navigation prior to 
the effective date of a final rule or any meteorological tower with the 
highest point of the structure at least 50 feet AGL up to and including 
200 feet AGL at its site for which construction is complete prior to 
the effective date of a final rule. This clarifying amendment is 
necessary to eliminate safety risks that were identified as a result of 
previous instances of non-compliance. Consistent application of marking 
requirements ensures the pilot's ability to properly recognize the 
obstructions and mitigate risk.
    Each newly constructed or altered meteorological tower with the 
highest point of the structure at least 50 feet AGL up to and including 
200 feet AGL at its site would receive conditions and limitations that 
include, at a minimum, marking requirements based upon AC 70/7460-1. 
Under the current part 77, proposed structures that meet notice 
criteria are subject to an FAA aeronautical study to assess potential 
impacts on the NAS. When the FAA completes an aeronautical study and 
issues a determination to the sponsor of a proposed or altered 
structure, the determination would contain conditions and limitations 
that include, at a minimum, marking requirements for meteorological 
towers with the highest point of the structure at least 50 feet AGL up 
to and including 200 feet AGL at its site.
    Part 77 does not currently require marking unless recommended by an 
aeronautical study. Current meteorological towers taller than 200 feet 
AGL fall under the current regulatory scheme requiring notice, an 
aeronautical study, and implementation of any FAA-specified risk-
mitigation measures. If adopted, the FAA's new rule would require the 
marking of all proposed and altered meteorological towers with the 
highest point of the structure at least 50 feet AGL up to and including 
200 feet AGL at its site in accordance with AC 70/7460-1. 
Meteorological towers can be erected in a matter of hours. As such, an 
operator who is familiar with the terrain may unexpectedly encounter a 
temporary structure. Moreover, depending on the materials used, a 
meteorological tower may be difficult to see in certain atmospheric 
conditions. The FAA determined that marking, such as painting towers, 
adding marker balls or sleeves to guy wires, and, if warranted, 
lighting new or altered meteorological towers would enhance their 
conspicuity to pilots who operate at low altitudes, such as 
agricultural operators, thereby reducing the likelihood of incidents 
and accidents.
    Moreover, although the states discussed in section III.D of this 
preamble have notice and marking requirements similar in some aspects 
to this FAA proposal, a NAS-wide application of standards will increase 
aviation safety, especially for those pilots operating at lower 
altitudes across state lines where meteorological tower standards may 
be inconsistent. Consistency may reduce confusion and increase a 
pilot's ability to see and avoid obstacles, either visually or with 
onboard electronics, regardless of what state they are flying in. The 
FAA proposed Sec.  77.32 to codify the existing process contained in 
the AC 70/7460-1 for requesting modifications to the marking and 
lighting conditions and limitations. The FAA is updating the process 
for requesting a deviation by requiring a sponsor to submit FAA Form 
7460-1 in the OE/AAA system for processing. The FAA is making this 
change to standardize the approval process. The proposed Sec.  77.32 
would codify this updated process. This change would be necessary if 
the conditions and limitations become requirements as proposed in this 
NPRM so that sponsors have a mechanism to seek changes to the 
requirements after the issuance of a determination.
    The FAA proposes to define ``sponsor'' in Sec.  77.3 as the owner 
of a structure for which notice is required under part 77. This would 
clarify the person that is required to provide the FAA with notice and 
is responsible for meeting the requirements of this proposed rule. A 
sponsor may allow a legally designated representative to fulfill the 
notice or other part 77 requirements on their behalf; however, the FAA 
must receive proper notice on the forms submitted to the FAA.
    The FAA proposes to revise references to ``Airport/Facility 
Directory, Alaska Supplement, or Pacific Chart Supplement'' to ``Chart 
Supplement U.S., Chart Supplement Alaska, or Chart Supplement Pacific'' 
throughout part 77 for consistency with the publications' current name.
    The FAA proposes to change all references throughout part 77 from 
``marking and lighting recommendations'' to ``marking and lighting 
requirements'' for consistency with proposed Sec.  77.12.
    Throughout the sections proposed to be revised in this NPRM 
(including Sec. Sec. Sec.  77.29(b), and 77.35(a) and (c)(1) through 
(3)), the FAA proposes to change references from ``you'' to ``sponsor'' 
to clarify to whom ``you'' refers.

F. Proposed Effective Date

    The FAA proposes to make these changes effective 30 days after the 
final rule is published in the Federal Register. This rule would also 
require sponsors of existing meteorological towers with the highest 
point of the structure at least 50 feet AGL up to and including 200 
feet AGL at its site to file notice within 90 days of the final rule's 
effective date pursuant to Sec.  77.9.

IV. Agency Guidance

    If this rule is finalized as proposed, the FAA would make changes 
to FAA AC 70/7460-1 to reflect that all conditions and limitations in a 
Determination of No Hazard to Air Navigation are mandatory pursuant to 
Sec.  77.12, including marking requirements for meteorological towers 
with the highest point of the structure at least 50 feet AGL up to and 
including 200 feet AGL at its site, except for structures that have 
received an FAA Determination of No Hazard to Air Navigation prior to 
the effective date of a final rule or any meteorological tower with the 
highest point of the structure at least 50 feet AGL up to and including 
200 feet AGL at its site for which construction is complete prior to 
the effective date of a final rule. FAA AC 70/7460-1 marking standards 
would continue to be recommendations when not part of a determination.
    The revised AC 70/7460-1 would direct sponsors to the most 
effective marking standards identified by the agency unless the FAA 
accepts an equally effective alternative. Revisions to AC 70/7460-1 
would contain the most effective painting and marking approaches 
identified by the FAA. For instance, meteorological towers would need 
to use spherical markers or cable balls, sleeves, and the identified 
painting scheme unless the sponsor presents an equally effective 
alternative accepted by the FAA. The AC would direct sponsors of newly 
proposed meteorological towers with the highest point of the structure 
at least 50 feet AGL up to and including 200 feet AGL at its site to 
comply with existing painting standards establishing color and pattern 
requirements. The AC would also suggest placing a total of 8 high-
visibility aviation orange spherical markers or cable balls, 4 attached 
to guy wires at the top of the tower no further than 15 feet from the 
top wire connection and 4 at or below the mid-point of the structure on 
the outer guy wires. The AC would also suggest the placement of two 
high-visibility sleeves

[[Page 90639]]

on each guy wire, one as close to the anchor point as possible and a 
second midway between the lower sleeve and the connection between wire 
and tower. The guidance would explain that sponsors may present 
alternate marking approaches should the FAA deem them equally 
effective. A copy of the proposed revised AC has been placed in the 
docket for this rulemaking. The FAA seeks comments on this draft 
revised AC.
    Finally, the FAA is updating the process for requesting a deviation 
from the marking and lighting standards in the AC during this 
rulemaking process.

V. Regulatory Notices and Analyses

    Federal agencies consider impacts of regulatory actions under a 
variety of executive orders and other requirements. First, Executive 
Order 12866, Executive Order 13563, and Executive Order 14094 
(``Modernizing Regulatory Review'') direct that each Federal agency 
propose or adopt a regulation only upon a reasoned determination that 
the benefits of the intended regulation justify the costs. Second, the 
Regulatory Flexibility Act of 1980 (Pub. L. 96-354) requires agencies 
to analyze the economic impact of regulatory changes on small entities. 
Third, the Trade Agreements Act (Pub. L. 96-39) prohibits agencies from 
setting standards that create unnecessary obstacles to the foreign 
commerce of the United States. Fourth, the Unfunded Mandates Reform Act 
of 1995 (Pub. L. 104-4) requires agencies to prepare a written 
assessment of the costs, benefits, and other effects of proposed or 
final rules that include a Federal mandate that may result in the 
expenditure by State, local, and Tribal governments, in the aggregate, 
or by the private sector, of $100,000,000 or more (adjusted annually 
for inflation) in any one year. The current threshold after adjustment 
for inflation is $183 million, using the most current (2023) Implicit 
Price Deflator for the Gross Domestic Product. The FAA has provided a 
detailed Regulatory Impact Analysis (RIA) in the docket for this 
rulemaking. This portion of the preamble summarizes the FAA's analysis 
of the economic impacts of this rule.
    In conducting these analyses, the FAA has determined that this 
rule: is not a ``significant regulatory action'' as defined in section 
3(f)(1) of Executive Order 12866 as amended by Executive Order 14094; 
may have a significant economic impact on a substantial number of small 
entities; will not create unnecessary obstacles to the foreign commerce 
of the United States; and will not impose an unfunded mandate on State, 
local, or Tribal governments, or on the private sector.

A. Summary of the Regulatory Evaluation

    Congress mandated that the FAA issue regulations to require marking 
of covered towers and inclusion of covered towers in a public database. 
The proposed rule would amend part 77 notice requirements as applicable 
to the construction or alteration of meteorological towers and wind 
turbines. The proposed rule responds to recommendations from the NTSB 
and aerial applicator organizations concerning fatal collisions between 
aerial applicators, private aircraft, and meteorological towers. The 
proposed rule also includes amendments that would allow the FAA to 
better study and determine potential impacts to the NAS from wind 
turbines.
    Consistent with the direction provided in section 2110 of FESSA, 
the FAA proposes to add Sec.  77.12 to require sponsors of new 
meteorological towers, constructed with the highest point of the 
structure at least 50 feet AGL up to and including 200 feet AGL at its 
site, to mark the towers in accordance with the determination except 
for structures that have received an FAA Determination of No Hazard to 
Air Navigation prior to the effective date of a final rule or any 
meteorological tower with the highest point of the structure at least 
50 feet AGL up to and including 200 feet AGL at its site for which 
construction is complete prior the effective date of a final rule. The 
FAA notes that the 2018 FAA Reauthorization Act requires the marking of 
meteorological towers constructed within 18 months after the enactment 
of the statutory mandate, or when the database is completed, whichever 
is first. Therefore, in the proposed Sec.  77.12, the FAA proposes to 
make the terms and conditions of a determination mandatory, which would 
include, at a minimum, sponsors to mark new or altered towers by the 
time construction is complete for meteorological towers with the 
highest point of the structure at least 50 feet AGL up to and including 
200 feet AGL at its site.
    The primary costs of the proposed rule to industry would be the 
costs to mark new and altered meteorological towers. The estimated 
additional costs to mark new or altered towers is about $14,300. This 
cost includes equipment costs for marker balls and sleeves and 
installing them to new and altered towers, buying a new pre-painted 
tower, and dismantling a tower. This also includes the cost to provide 
the FAA notifications of both existing and dismantling of out-of-
service meteorological towers. The FAA would process notifications of 
existing and new meteorological towers, including notifications of 
dismantled out-of-service meteorological towers. Processing these 
notifications would cost the FAA about $41 per existing notification 
and about $163 per dismantling notification. The primary benefit of the 
proposed rule would be enhanced conspicuity to prevent agricultural 
pilots from colliding with meteorological towers with the highest point 
of the structure at least 50 feet AGL up to and including 200 feet AGL 
at its site.

B. Regulatory Flexibility Act

    The Regulatory Flexibility Act (RFA) of 1980 (5 U.S.C. 601-612), as 
amended by the Small Business Regulatory Enforcement Fairness Act of 
1996 (Pub. L. 104-121) and the Small Business Jobs Act of 2010 (Pub. L. 
111-240), requires Federal agencies to consider the effects of the 
regulatory action on small business and other small entities and to 
minimize any significant economic impact. The term ``small entities'' 
comprises small businesses, not-for-profit organizations that are 
independently owned and operated and are not dominant in their fields, 
and governmental jurisdictions with populations of less than 50,000.
    The FAA is publishing this Initial Regulatory Flexibility Analysis 
(IRFA) to aid the public in commenting on the potential impacts to 
small entities from this proposal. The FAA invites interested parties 
to submit data and information regarding the potential economic impact 
that would result from the proposal. The FAA will consider comments 
when making a determination or when completing a Final Regulatory 
Flexibility Analysis.
    Under Section 603(b) and (c) of the RFA, an IRFA must contain the 
following:
    (1) A description of the reasons why the action by the agency is 
being considered;
    (2) A succinct statement of the objective of, and legal basis for, 
the proposed rule;
    (3) A description of and, where feasible, an estimate of the number 
of small entities to which the proposed rule will apply;
    (4) A description of the projected reporting, recordkeeping, and 
other compliance requirements of the proposed rule, including an 
estimate of the classes of small entities that will be subject to the 
requirement and the type

[[Page 90640]]

of professional skills necessary for preparation of the report or 
record;
    (5) An identification, to the extent practicable, of all relevant 
Federal rules that may duplicate, overlap, or conflict with the 
proposed rule; and
    (6) A description of any significant alternatives to the proposed 
rule that accomplish the stated objectives of applicable statutes and 
which minimize any significant economic impact of the proposed rule on 
small entities.
1. Reasons the Action Is Being Considered
    This rulemaking proposes to amend part 77 as it applies to the 
proposed construction or alteration of meteorological towers and wind 
energy systems. The proposed changes applicable to meteorological 
towers address safety recommendations from the NTSB and industry 
recommendations.
    This proposal also partially implements the statutory requirements 
in section 2110 of FESSA. Specifically, the FAA proposes these 
amendments applicable to meteorological towers:
     Extend notice requirements to the proposed construction or 
alteration of meteorological towers with the highest point of the 
structure at least 50 feet AGL up to and including 200 feet AGL at its 
site. Sponsors would be required to file a notice of construction with 
the FAA within the current timeframe in Sec.  77.7(b); \45\ and,
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    \45\ Notice requirements for meteorological towers are necessary 
to give effect to section 2110 that requires inclusion of all 
meteorological towers in the FAA's public DOF database.
---------------------------------------------------------------------------

     Extend notice requirements to existing meteorological 
towers at least 50 feet AGL up to and including 200 feet AGL at its 
site. Sponsors would be required to file a notice with the FAA within 
90 days of the final rule's effective date.
    In addition, the FAA proposes the following amendments applicable 
to wind energy systems to clarify and accurately reflect circumstances 
unique to these structures:
     Require the earlier filing of notice for the proposed 
construction or alteration of wind energy systems. Notice would be due 
90 days before, as opposed to the current 45 days before, the start 
date of the proposed construction or alteration, or the date an 
application for a construction permit is filed, whichever is earlier; 
and
     Increase the duration of a Determination of No Hazard to 
Air Navigation with regard to wind energy systems and associated 
meteorological towers proposals from the current 18 months to 36 
months.
    Finally, this proposed rule would make additional non-substantive 
changes to clarify agency practice as a result of the proposed 
substantive changes. These changes would:
     Amend purpose in Sec.  77.1 to reflect that part 77 would 
include requirements for marking proposed meteorological towers;
     Define ``airborne wind energy system (AWES)'' in Sec.  
77.3 consistent with the FAA's 2022 final notice of policy. AWES would 
mean a structure, which consists of a self-supported airborne system 
tethered to a ground station, with an airborne or ground-mounted 
drivetrain used to convert kinetic energy in the wind to mechanical 
power for the purpose of generating electricity;
     Define ``sponsor'' in Sec.  77.3 as the owner of a 
structure for which notice is required under part 77. This would 
clarify the person that is required to provide the FAA with notice and 
is responsible for meeting the requirements of part 77. A sponsor may 
allow a legally designated representative to fulfill the notice or 
other part 77 requirements on its behalf; however, the FAA must receive 
proper notice on the forms submitted to the FAA.
     Redesignate Sec.  77.11 as Sec.  77.10 and clarify the 
FAA's current practice with regard to supplemental notice. The proposed 
amendment also identifies the form (FAA Form 7460-2, Notice of Actual 
Construction or Alteration) sponsors currently use to provide 
supplemental notice.
     Add Sec.  77.11 to require the sponsor to provide specific 
data to the FAA after filing a notice of construction when the FAA 
determines that additional information is necessary to properly 
complete an aeronautical study.
     Add Sec.  77.12 to require all sponsors to comply with the 
conditions and limitations contained in their determination except for 
structures that have received an FAA Determination of No Hazard to Air 
Navigation prior to the effective date of a final rule or any 
meteorological tower with the highest point of the structure at least 
50 feet AGL up to and including 200 feet AGL at its site for which 
construction is complete prior to the effective date of a final rule. 
This would require, at a minimum, proposed or altered meteorological 
towers with the highest point of the structure at least 50 feet AGL up 
to and including 200 feet AGL at its site to mark towers consistent 
with the conditions and limitations of the determination.
     Add Sec.  77.32 to require sponsors to request a 
modification from the marking and lighting requirements in a 
determination to submit FAA Form 7460-1, Notice of Proposed 
Construction or Alteration.
2. Objectives and Legal Basis of the Proposed Rule
    The FAA's authority to issue rules on aviation safety is found in 
49 U.S.C. Subtitle I, section 106 describes the authority of the FAA 
Administrator. Subtitle VII, Aviation Programs, describes in more 
detail the scope of the agency's authority.
    This rulemaking is issued under the authority described in 49 
U.S.C. 40103(b), which vests the administrator with broad authority to 
prescribe regulations to ensure the safety of aircraft and the 
efficient use of airspace, and 49 U.S.C. 44701(a)(5), which requires 
the Administrator to promulgate regulations and minimum standards for 
other practices, methods, and procedures necessary for safety in air 
commerce and national security. This rulemaking is also consistent 
with: the authority in 49 U.S.C. 44718(a), which directs the Secretary 
of Transportation to require a person to give adequate public notice of 
the construction, alteration, establishment, or expansion, or the 
proposed construction, alteration, establishment, or expansion, of a 
structure or sanitary landfill in furtherance of safety in air commerce 
and the efficient use and preservation of the navigable airspace and of 
airport traffic capacity at public-use airports; section 44718(b), 
which requires the Secretary to conduct an aeronautical study to decide 
the extent of any adverse impact on the safe and efficient use of the 
airspace, space navigation facilities, or equipment if the secretary 
decides that constructing or altering a structure may result in an 
obstruction of the navigable airspace or an interference with air 
navigation facilities and equipment or the navigable airspace; and 
section 44718(c), which requires that in carrying out laws related to a 
broadcast application and conducting an aeronautical study related to 
broadcast towers, the FAA Administrator and the FCC shall take action 
necessary to coordinate efficiently the receipt and consideration of, 
and action on, the application; and the completion of any associated 
aeronautical study. These proposed amendments to part 77, applicable to 
the construction or alteration of meteorological towers and wind energy 
systems, are within the scope of this authority.
    Authority for this rulemaking is further derived from the FAA 
Reauthorization Act of 2018, section 576, which revised section 2110 of 
the

[[Page 90641]]

FAA Extension, Safety, and Security Act of 2016. Section 2110 requires 
that the FAA issue regulations to require the marking of meteorological 
towers. Moreover, section 2110 requires that all covered towers 
constructed on or after the date on which such regulations take effect 
be marked or included in the database. Further, the section requires 
the marking of meteorological towers and their inclusion within an FAA 
database. Section 2110 also directs the FAA to ``develop a database 
that contains the location and height of each covered tower [including 
meteorological towers];'' keep the database current to the extent 
practicable; and ensure that any proprietary information in the 
database is protected from disclosure in accordance with the law. This 
section also requires that by virtue of accessing the database, users 
agree and acknowledge that information in the database may only be used 
for aviation safety purposes and may not be disclosed for purposes 
other than aviation safety, regardless of whether the information is 
marked or labeled as proprietary or with a similar designation. 
Publication of this NPRM also satisfies the requirements in 355 of the 
FAA Reauthorization Act of 2024, which requires the FAA to publish this 
notice of proposed rulemaking within one year of the date of enactment 
of the 2024 Act.
3. Description and Estimate of the Number of Small Entities
    The FAA used the definition of small entities in the RFA for this 
analysis. The RFA defines small entities as small businesses, small 
governmental jurisdictions, or small organizations. In 5 U.S.C. 601(3), 
the RFA defines ``small business'' to have the same meaning as ``small 
business concern'' under section 3 of the Small Business Act. The Small 
Business Act authorizes the Small Business Administration (SBA) to 
define ``small business'' by issuing regulations. SBA (2023) has 
established size standards for various types of economic activities or 
industries under the North American Industry Classification System 
(NAICS).\46\ These size standards generally define small businesses 
based on the number of employees or annual receipts. Note that the SBA 
definition of a small business applies to the parent company and all 
affiliates as a single entity.
---------------------------------------------------------------------------

    \46\ Small Business Administration (SBA). 2023. Table of Size 
Standards. Effective March 17, 2023. https://www.sba.gov/document/support--table-size-standards.
---------------------------------------------------------------------------

    To identify small entities, the FAA first identified the primary 
NAICS of the parent company and then used data from different sources 
(e.g., company annual reports, Bureau of Transportation Statistics, 
etc.) to determine whether the parent company meets the applicable size 
standard. Businesses affected by this rule are classified using the 
2022 NAICS \47\ under NAICS code 221115 ``Wind Electric Power 
Generation.'' This industry comprises establishments primarily engaged 
in operating wind electric power generation facilities. These 
facilities use wind power to drive a turbine and produce electric 
energy. The electric energy produced in these establishments is 
provided to electric power transmission systems or electric power 
distribution systems. The U.S. SBA defines entities in this industry as 
``small''--those that employ fewer than 1,150 employees.\48\ With 
limited information and incomplete data on employment sizes for each of 
the affected meteorological tower operators, the FAA is uncertain as to 
how many entities would meet the SBA's small-entity criteria. 
Furthermore, the FAA is uncertain as to how the burden associated with 
the proposed rule would be distributed across meteorological tower 
companies. The FAA requests comments and data on the average annual 
sales revenues for the affected small businesses and to what extent the 
costs would impact these entities.
---------------------------------------------------------------------------

    \47\ North American Industry Classification System (NAICS) U.S. 
Census Bureau https://www.census.gov/naics/?input=221115&year=2022&details=221115.
    \48\ https://www.sba.gov/sites/default/files/2023-06/Table%20of%20Size%20Standards_Effective%20March%2017%2C%202023%20%282%29.pdf.
---------------------------------------------------------------------------

    For purposes of this IRFA, the FAA assumes that the private sector 
costs of this proposed rule would fall entirely on the sponsors of 
meteorological towers. In the absence of data on annual receipts 
specific to this industry, the FAA relies on the most recent data 
available on average revenues for all businesses classified under NAICS 
221115 ``Wind Electric Power Generation'' from the 2017 Census Bureau's 
Statistics of U.S. Businesses (SUSB) \49\ to inform the analysis. The 
data indicates 98 firms with 611 entities in this NAICS.
---------------------------------------------------------------------------

    \49\ Available at: https://www.census.gov/data/tables/2017/econ/susb/2017-susb-annual.html, retrieved on April 15, 2023.
---------------------------------------------------------------------------

    The proposed rule would affect sponsors, or legally designated 
representatives, of any proposed meteorological tower, altered 
meteorological tower, or existing meteorological tower if the highest 
point of the structure is at least 50 feet AGL up to and including 200 
feet AGL at its site. From 2021 to 2023, 39 states submitted 391 
voluntary new filings for proposed meteorological towers at least 50 
feet AGL up to and including 200 feet AGL at its site to the FAA.
    In the absence of more financial data from small entities and the 
profile of small entities, the FAA is unable to assess the proposed 
rule's economic impact on them.
4. Projected Reporting, Recordkeeping, and Other Compliance 
Requirements
    In absence of more detailed data on small entities, it is difficult 
to estimate the number of meteorological towers they own. The FAA 
assumes that small entities own about two to five meteorological towers 
per entity. The below estimates the paperwork burden cost to file a 
notice with the FAA. The FAA estimates a sponsor of a new 
meteorological tower would incur $14,301 in additional costs per new 
tower due to the proposed rule.
    New meteorological towers would have to be painted and marked. It 
likely is more economical to purchase a pre-painted meteorological 
tower, about an additional $2,800, instead of painting a non-marked 
tower. Eight marker balls costing about $2,000 and eight sleeves 
costing about $101 would have to be installed as part of the marking 
requirements.\50\ The FAA assumes the installation cost per tower for 
the marker ball and sleeves to take four hours and cost $390.\51\ Based 
on the industry's experience, the FAA expects minimal additional labor 
cost for sponsors of new meteorological towers to comply with the 
proposed rule's marking requirement, because marker balls and sleeves 
could be attached to the guy wires before raising the new 
meteorological tower as opposed to incurring costs to lower, mark, and 
raise the meteorological tower. The FAA estimates that it would take 
two contractors about two hours to attach marker balls and sleeves to 
the new meteorological tower. The total hourly compensation per 
contractor is $97.62.\52\
---------------------------------------------------------------------------

    \50\ Cost estimates based on a call with NRG Systems on 4/1/
2023.
    \51\ Labor cost to install marker balls/sleeves = (T x W), where 
T is the total time it would take for contractors to install marker 
balls and sleeves (T=4 hours); and W is the hourly wage rate for a 
contractor (W=$97.62).
    \52\ The hourly wage rate ($63.50) was provided by National 
Association of Tower Erectors (NATE) on 11/1/2017 and updated with 
the GDP deflator from 2017 to 2022, 18.8%. U.S. Bureau of Economic 
Analysis, ``Table 1.1.7. Percent Change From Preceding Period in 
Prices for Gross Domestic Product'' (accessed on 2/7/2024). The 
benefit rate of 29.4% was also added to estimate the fully loaded 
hourly wage rate. https://www.bls.gov/news.release/archives/ecec_12152023.pdf, accessed on 1/29/2024.

---------------------------------------------------------------------------

[[Page 90642]]

    The cost to dismantle a meteorological tower is between $5,000 and 
$22,500. The FAA estimates the most likely cost would be around 
$9,000.\53\ Sponsors of out-of-service meteorological towers would 
choose to dismantle them because the recurring costs to comply with the 
proposed rule outweigh the costs to dismantle them.
---------------------------------------------------------------------------

    \53\ Cost estimate based on a conference call with NATE on 11/1/
2017.
---------------------------------------------------------------------------

    Under Sec.  77.9, the proposed rule would require sponsors of both 
existing and proposed construction and altered meteorological towers 
with the highest point of the structure at least 50 feet AGL up to and 
including 200 feet AGL at its site to file notice with the FAA. In 
addition, Sec.  77.11 would also require sponsors to file FAA Form 
7460-2 after dismantling meteorological towers.
    To comply with these requirements, an office worker would complete 
the submission of information required for the FAA aeronautical study, 
provided they have all the relevant meteorological tower data and the 
management has all the critical data on the meteorological tower(s). 
The FAA estimates the fully loaded hourly average wage rate for an 
office worker to be $28.34.\54\
---------------------------------------------------------------------------

    \54\ Fully loaded Hourly Wage Rate = hourly wage rate + (benefit 
rate x hourly wage rate). U.S. Bureau of Labor Statistics: Office 
and Administrative Support Occupations, $21.90 mean hourly wage 
rate, https://www.bls.gov/oes/2022/may/oes_nat.htm#43-0000, accessed 
on 4/10/2023. 29.4% benefit rate: https://www.bls.gov/news.release/archives/ecec_12152023.pdf, accessed on 1/29/2024.
---------------------------------------------------------------------------

    Respondents: The FAA is unable to estimate the number of existing 
meteorological towers and the annual number of new meteorological 
towers with the highest point of the structure at least 50 feet AGL up 
to and including 200 feet AGL at its site due to the lack of federal 
regulations governing these meteorological towers.
    Frequency: Sponsors of all existing meteorological towers with the 
highest point of the structure at least 50 feet AGL up to and including 
200 feet AGL at its site would have to file notice to the FAA 90 days 
after the effective date of a final rule. In addition, sponsors would 
submit another notice to the FAA whenever they propose to construct or 
alter meteorological towers. When sponsors decide to dismantle a 
meteorological tower, the proposed rule would require them to file FAA 
Form 7460-2.
    Annual Burden Estimate: The FAA estimates that it would take a 
sponsor of a meteorological tower with the highest point of the 
structure at least 50 feet AGL up to and including 200 feet AGL at its 
site 0.25 hours (or 15 minutes) to file FAA Form 7460-1 electronically. 
Similarly, FAA Form 7460-2 would take about 0.1 hours (6 minutes) to 
file notice electronically. The FAA estimates that it would cost about 
$7 to file Form 7460-1 ($28.34 x 0.25 hours) and $3 to file Form 7460-2 
($28.34 x 0.10 hours).
5. All Federal Rules That May Duplicate, Overlap, or Conflict
    There are no Federal rules that may duplicate, overlap, or conflict 
with the proposed rule.
6. Significant Alternatives Considered
    To comply with the proposed rule, the impacted small entities would 
have to incur a small cost to file notices with the FAA. The FAA found 
no other alternatives that could meet the objectives of the proposed 
rule with less burden on these small entities.

C. International Trade Impact Assessment

    The Trade Agreements Act of 1979 (Pub. L. 96-39), as amended by the 
Uruguay Round Agreements Act (Pub. L. 103-465), prohibits Federal 
agencies from establishing standards or engaging in related activities 
that create unnecessary obstacles to the foreign commerce of the United 
States. Pursuant to these Acts, the establishment of standards is not 
considered an unnecessary obstacle to the foreign commerce of the 
United States, so long as the standard has a legitimate domestic 
objective, such as the protection of safety, and does not operate in a 
manner that excludes imports that meet this objective. The statute also 
requires consideration of international standards and, where 
appropriate, that they be the basis for U.S. standards. The FAA has 
assessed the potential effect of this rule and determined that it will 
only have a domestic impact and, therefore, no effect on international 
trade.

D. Unfunded Mandates Assessment

    The Unfunded Mandates Reform Act of 1995 (2 U.S.C. 1531-1538) 
governs the issuance of Federal regulations that require unfunded 
mandates. An unfunded mandate is a regulation that requires a State, 
local, or tribal government or the private sector to incur direct costs 
without the Federal government having first provided the funds to pay 
those costs. The FAA determined that the proposed rule will not result 
in the expenditure of $183 million or more by State, local, or Tribal 
governments, in the aggregate, or the private sector, in any one year.

E. Paperwork Reduction Act

    The Paperwork Reduction Act of 1995 (44 U.S.C. 3507(d)) requires 
that the FAA consider the impact of paperwork and other information 
collection burdens imposed on the public. According to the 1995 
amendments to the Paperwork Reduction Act (5 CFR 1320.8(b)(2)(vi)), an 
agency may not collect or sponsor the collection of information, nor 
may it impose an information collection requirement unless it displays 
a currently valid Office of Management and Budget (OMB) control number. 
The FAA routinely renews its ongoing information collection under OMB 
Control Number 2120-0001 and intends to continue to collect notice 
information via the OMB-approved FAA Forms 7460-1 and 7460-2, which are 
the instruments of the information collection.
    Under Sec.  77.9, the proposed rule would require owners of both 
existing and proposed construction and altered meteorological towers 
with the highest point of the structure at least 50 feet AGL up to and 
including 200 feet AGL at its site to file notice with the FAA using 
Form 7460-1. In addition, Sec.  77.10 would also require owners to file 
FAA Form 7460-2 after dismantling meteorological towers.
    To comply with these requirements, an office worker would complete 
the submission of information required for the FAA aeronautical study, 
provided they have all the relevant meteorological tower data and the 
management has all the critical data on the meteorological tower(s). 
The FAA estimates the fully loaded hourly average wage rate for an 
office worker to be $28.34.\55\
---------------------------------------------------------------------------

    \55\ Fully loaded Hourly Wage Rate = hourly wage rate + (benefit 
rate x hourly wage rate). U.S. Bureau of Labor Statistics: Office 
and Administrative Support Occupations, $21.90 mean hourly wage 
rate, https://www.bls.gov/oes/2022/may/oes_nat.htm#43-0000, accessed 
on 4/10/2023. 29.4% benefit rate: https://www.bls.gov/news.release/archives/ecec_12152023.pdf, accessed on 1/29/2024.
---------------------------------------------------------------------------

    Respondents: The FAA cannot estimate the additional number of 
existing meteorological towers and the annual number of new 
meteorological towers with the highest point of the structure at least 
50 feet AGL up to and including 200 feet AGL at its site due to the 
lack of federal regulations governing these meteorological towers.
    Frequency: Sponsors of existing all meteorological towers with the 
highest point of the structure at least 50 feet AGL up to and including 
200 feet AGL

[[Page 90643]]

at its site would have to file notice to the FAA 90 days after the 
effective date of a final rule. In addition, sponsors would submit 
another notice to the FAA whenever they propose to construct or alter a 
meteorological tower. When sponsors decide to dismantle a 
meteorological tower, the proposed rule would require them to file FAA 
Form 7460-2.
    Annual Burden Estimate: The FAA estimates that it would take a 
sponsor of a meteorological tower with the highest point of the 
structure at least 50 feet AGL up to and including 200 feet AGL at its 
site 0.25 hours (or 15 minutes) to file a notice electronically. 
Similarly, FAA Form 7460-2 would take about 0.1 hours (6 minutes) to 
file notice electronically. The FAA estimates that it would cost about 
$7 to file Form 7460-1 ($28.34 x 0.25 hours) and $3 to file Form 7460-2 
($28.34 x 0.10 hours).
    The FAA is soliciting comments to--
    (1) Evaluate whether the proposed information requirement is 
necessary for the proper performance of the functions of the FAA, 
including whether the information will have practical utility;
    (2) Evaluate the accuracy of the FAA's estimate of the burden;
    (3) Enhance the quality, utility, and clarity of the information to 
be collected; and
    (4) Minimize the burden of collecting information on those who are 
to respond, including by using appropriate automated, electronic, 
mechanical, or other technological collection techniques or other forms 
of information technology.
    Individuals and organizations may send comments on the information 
collection requirement to the address listed in the ADDRESSES section 
at the beginning of this preamble by January 17, 2025. Comments also 
should be submitted to the Office of Management and Budget, Office of 
Information and Regulatory Affairs, Attention: Desk Officer for FAA, 
New Executive Office Building, Room 10202, 725 17th Street NW, 
Washington, DC 20053.

F. International Compatibility and Cooperation

    In keeping with U.S. obligations under the Convention on 
International Civil Aviation, it is FAA policy to conform to 
International Civil Aviation Organization (ICAO) Standards and 
Recommended Practices to the maximum extent practicable. The FAA 
determined that there are no ICAO Standards and Recommended Practices 
that correspond to these regulations.

G. Environmental Analysis

    FAA Order 1050.1F identifies FAA actions that are categorically 
excluded from preparation of an environmental assessment or 
environmental impact statement under the National Environmental Policy 
Act in the absence of extraordinary circumstances. The FAA determined 
this rulemaking action qualifies for a categorical exclusion per 
paragraph 5-6.6f for regulations and involves no extraordinary 
circumstances.

VI. Executive Order Determinations

A. Executive Order 13132, Federalism

    The FAA analyzed this proposed rule under the principles and 
criteria of Executive Order 13132, Federalism. The agency determined 
that this action would not have a substantial direct effect on the 
States, or the relationship between the Federal Government and the 
States, or on the distribution of power and responsibilities among the 
various levels of government and, therefore, would not have Federalism 
implications.

B. Executive Order 13211, Regulations That Significantly Affect Energy 
Supply, Distribution, or Use

    The FAA analyzed this proposed rule under Executive Order 13211, 
Actions Concerning Regulations that Significantly Affect Energy Supply, 
Distribution, or Use. The agency determined that this action would not 
be a ``significant energy action'' under the executive order and would 
not be likely to have a significant adverse effect on the supply, 
distribution, or use of energy.

C. Executive Order 13609, International Cooperation

    Executive Order 13609, Promoting International Regulatory 
Cooperation, promotes international regulatory cooperation to meet 
shared challenges involving health, safety, labor, security, 
environmental, and other issues and to reduce, eliminate, or prevent 
unnecessary differences in regulatory requirements. The FAA analyzed 
this proposed rule under the policies and agency responsibilities under 
the executive order and determined that this action would have no 
effect on international regulatory cooperation.

VII. Additional Information

A. Comments Invited

    The FAA invites interested persons to participate in this 
rulemaking by submitting written comments, data, or views. The FAA also 
invites comments relating to the economic, environmental, energy, or 
federalism impacts that might result from adopting the proposals in 
this document. The most helpful comments reference a specific portion 
of the proposal, explain the reason for any recommended change, and 
include supporting data. To ensure the docket does not contain 
duplicate comments, commenters should submit only one time if comments 
are filed electronically, or commenters should send only one copy of 
written comments if comments are filed in writing.
    The FAA will file in the docket all comments it receives, as well 
as a report summarizing each substantive public contact with FAA 
personnel concerning this proposed rulemaking. Before acting on this 
proposal, the FAA will consider all comments it receives on or before 
the closing date for comments. The FAA will consider comments filed 
after the comment period has closed if it is possible to do so without 
incurring expense or delay. The FAA may change this proposal in light 
of the comments it receives.
    Privacy: In accordance with 5 U.S.C. 553(c), DOT solicits comments 
from the public to better inform its rulemaking process. DOT posts 
these comments, without edit, including any personal information the 
commenter provides, to https://www.regulations.gov, as described in the 
system of records notice (DOT/ALL-14 FDMS), which can be reviewed at 
https://www.dot.gov/privacy.

B. Confidential Business Information

    Confidential Business Information (CBI) is commercial or financial 
information that is both customarily and actually treated as private by 
its owner. Under the Freedom of Information Act (FOIA) (5 U.S.C. 552), 
CBI is exempt from public disclosure. If your comments responsive to 
this NPRM contain commercial or financial information that is 
customarily treated as private, that you actually treat as private, and 
that is relevant or responsive to this NPRM, it is important that you 
clearly designate the submitted comments as CBI. Please mark each page 
of your submission containing CBI as ``PROPIN.'' The FAA will treat 
such marked submissions as confidential under the FOIA, and they will 
not be placed in the public docket of this NPRM. Submissions containing 
CBI should be sent to the person in the FOR FURTHER INFORMATION CONTACT 
section of this document. Any commentary that the FAA receives that is 
not specifically designated as CBI will be placed in the public docket 
for this rulemaking.

[[Page 90644]]

C. Electronic Access and Filing

    A copy of this NPRM, all comments received, any final rule, and all 
background material may be viewed online at https://www.regulations.gov 
using the docket number listed above. A copy of this proposed rule will 
be placed in the docket. Electronic retrieval help and guidelines are 
available on the website. It is available 24 hours each day, 365 days 
each year. An electronic copy of this document may also be downloaded 
from the Office of the Federal Register's website at https://www.federalregister.gov and the Government Publishing Office's website 
at https://www.govinfo.gov. A copy may also be found on the FAA's 
Regulations and Policies website at https://www.faa.gov/regulations_policies.
    Copies may also be obtained by sending a request to the Federal 
Aviation Administration, Office of Rulemaking, ARM-1, 800 Independence 
Avenue SW, Washington, DC 20591, or by calling (202) 267-9677. 
Commenters must identify the docket or notice number of this 
rulemaking.
    All documents the FAA considered in developing this proposed rule, 
including economic analyses and technical reports, may be accessed in 
the electronic docket for this rulemaking.

List of Subjects in 14 CFR Part 77

    Aeronautical study, Air Navigation, Airspace, Aviation safety, 
Construction or Alteration, Determination, Notice, Obstruction, 
Reporting and recordkeeping requirements.

The Proposed Amendment

    In consideration of the foregoing, the Federal Aviation 
Administration proposes to amend chapter I of title 14, Code of Federal 
Regulations as follows:

PART 77--SAFE, EFFICIENT USE, AND PRESERVATION OF THE NAVIGABLE 
AIRSPACE

0
1. The authority citation for part 77 is revised to read as follows:

    Authority: 49 U.S.C. 106(f), 40103, 40113-40114, 44502, 44701, 
44718, 46101-46102, 46104; Sec. 2110 of Pub. L. 114-190, 130 Stat. 
623 (49 U.S.C. 44718 note); Sec. 576 of Pub. L. 115-254, 132 Stat. 
3391 (49 U.S.C. 44718 note); Sec. 355 of Pub. L 118-63.

0
2. Revise Sec.  77.1 to read as follows:


Sec.  77.1  Purpose.

    This part establishes:
    (a) The requirements to provide notice to the FAA of the proposed 
construction, alteration, or existence of certain structures;
    (b) The standards used to determine obstructions to air navigation 
and navigational and communication facilities or equipment;
    (c) The process for aeronautical studies of obstructions to air 
navigation or navigational facilities to determine the effect on the 
safe and efficient use of navigable airspace, air navigation 
facilities, or equipment;
    (d) The process to petition the FAA for discretionary review of 
determinations, revisions, and extensions of determinations; and
    (e) The requirement to comply with the conditions and limitations 
contained in a Determination of No Hazard to Air Navigation, including 
the requirement to mark newly constructed or altered meteorological 
towers with the highest point of the structure at least 50 feet AGL up 
to and including 200 feet AGL at its site.
0
3. Amend Sec.  77.3 by adding definitions for ``airborne wind energy 
system (AWES),'' ``meteorological tower,'' ``sponsor,'' and ``wind 
energy system'' in alphabetical order to read as follows:


Sec.  77.3  Definitions.

* * * * *
    Airborne wind energy system (AWES) means a structure, which 
consists of a self-supported airborne system tethered to a ground 
station, with an airborne or ground-mounted drivetrain used to convert 
kinetic energy in the wind to mechanical power for the purpose of 
generating electricity.
    Meteorological tower means a skeletal or pole-type structure, 
either freestanding or anchored with guy wires, configured with 
components to measure wind speed and wind direction at different 
heights above ground level to assess local wind energy resources.
* * * * *
    Sponsor means the owner of a structure for which notice is required 
under this part.
* * * * *
    Wind energy system means a structure that converts kinetic energy 
in the wind to electrical energy. A wind energy system may consist of a 
single structure or a group of structures.
0
4. Revise the heading of subpart B to read as follows:

Subpart B--Notice and Determination Requirements

0
5. Revise Sec.  77.5 to read as follows:


Sec.  77.5  Applicability.

    (a) A sponsor of a meteorological tower in existence before the 
effective date of a final rule must provide notice consistent with 
Sec.  77.7(d).
    (b) A sponsor proposing any construction or alteration described in 
Sec.  77.9 must provide adequate notice to the FAA of that construction 
or alteration.
    (c) If requested by the FAA, a sponsor must file supplemental 
notice before the start date and upon completion of certain 
construction or alterations described in Sec.  77.9.
    (d) A sponsor proposing any construction or alteration of a 
meteorological tower with the highest point of the structure at least 
50 feet AGL up to and including 200 feet AGL at its site must provide 
adequate notice to the FAA of that construction or alteration pursuant 
to Sec.  77.7(b).
    (e) Notice received by the FAA under this subpart is used to:
    (1) Evaluate the effect of the proposed construction or alteration 
on safety in air commerce and the efficient use and preservation of the 
navigable airspace and of airport traffic capacity at public use 
airports;
    (2) Determine whether the effect of proposed construction or 
alteration is a hazard to air navigation;
    (3) Determine appropriate marking and lighting requirements using 
FAA Advisory Circular 70/7460-1, Obstruction Marking and Lighting.
    (4) Determine other appropriate measures required for continued 
safety of air navigation;
    (5) Notify the aviation community of the construction or alteration 
of objects that affect the navigable airspace, including the revision 
of charts, when necessary;
    (6) Evaluate the effect of a meteorological tower in existence 
before the effective date of a final rule on safety in air commerce and 
the efficient use and preservation of the navigable airspace and of 
airport traffic capacity at public use airports; and
    (7) Determine whether the effect of a meteorological tower in 
existence before the effective date of a final rule is a hazard to air 
navigation.
0
6. Revise Sec.  77.7 to read as follows:


Sec.  77.7  Form and time of notice.

    (a) Forms. The sponsor must electronically complete and submit FAA 
Form 7460-1, Notice of Proposed Construction or Alteration, or FAA Form 
7460-2, Notice of Actual Construction or Alteration, via the internet 
at https://oeaaa.faa.gov.
    (b) 45-day notice. Except as provided in paragraphs (c), (d), or 
(e) of this section, a sponsor required to provide notice under Sec.  
77.9 must submit FAA Form 7460-1 at least 45 days before the start date 
of the proposed construction or alteration, or the date an application

[[Page 90645]]

for a construction permit is filed, whichever is earlier.
    (1) If a sponsor proposes construction or alteration that is also 
subject to the licensing requirements of the Federal Communications 
Commission (FCC), the sponsor must submit notice to the FAA on or 
before the date that the application is filed with the FCC.
    (2) If a sponsor proposes construction or alteration to an existing 
structure that exceeds 2,000 feet in height AGL, the FAA presumes it to 
be a hazard to air navigation that results in an inefficient use of 
airspace. The sponsor must include details explaining both why the 
proposal would not constitute a hazard to air navigation and why it 
would not cause an inefficient use of airspace.
    (c) Wind energy system notice. A sponsor must submit FAA Form 7460-
1 for any proposed construction or alteration of a permanent wind 
energy system and associated meteorological tower at least 90 days 
before the start date of the proposed construction or alteration, or 
the date an application for a construction permit is filed, whichever 
is earlier. A meteorological tower is associated with a wind energy 
system when it is included in a wind energy systems project and is 
intended to be permanent. A meteorological tower is permanent when it 
is intended to remain in place for the duration of its lifecycle.
    (d) Existing meteorological tower notice. A sponsor of a 
meteorological tower that exists prior to the effective date of a final 
rule with the highest point of the structure at least 50 feet AGL up to 
and including 200 feet AGL at its site must submit FAA Form 7460-1 
within 90 days of the effective date of a final rule.
    (e) Waiver. The applicable notice requirement is waived if 
immediate construction or alteration is required because of an 
emergency involving essential public services, public health, or public 
safety. The sponsor may provide notice to the FAA by any available, 
expeditious means. The sponsor must file a completed FAA Form 7460-1 
within 5 days of the initial notice to the FAA.
0
7. Revise Sec.  77.9 to read as follows:


Sec.  77.9  Notice requirement.

    (a) If requested by the FAA, or if the sponsor proposes any of the 
following types of construction or alteration, a sponsor must file 
notice with the FAA of:
    (1) Any construction or alteration of a structure that is more than 
200 feet AGL at its site.
    (2) Any construction or alteration of a meteorological tower with 
the highest point of the structure at least 50 feet AGL up to and 
including 200 feet AGL at its site.
    (3) Any construction or alteration that exceeds an imaginary 
surface extending outward and upward at any of the following slopes:
    (i) 100 to 1 for a horizontal distance of 20,000 feet from the 
nearest point of the nearest runway of each airport described in 
paragraph (d) of this section with its longest runway more than 3,200 
feet in actual length, excluding heliports.
    (ii) 50 to 1 for a horizontal distance of 10,000 feet from the 
nearest point of the nearest runway of each airport described in 
paragraph (d) of this section with its longest runway no more than 
3,200 feet in actual length, excluding heliports.
    (iii) 25 to 1 for a horizontal distance of 5,000 feet from the 
nearest point of the nearest landing and takeoff area of each heliport 
described in paragraph (d) of this section.
    (4) Any highway, railroad, or other traverse way for mobile objects 
of a height which, if adjusted upward 17 feet for an Interstate Highway 
that is part of the National System of Military and Interstate Highways 
where overcrossings are designed for a minimum of 17 feet vertical 
distance, 15 feet for any other public roadway, 10 feet or the height 
of the highest mobile object that would normally traverse the road, 
whichever is greater, for a private road, 23 feet for a railroad, and 
for a waterway or any other traverse way not previously mentioned, an 
amount equal to the height of the highest mobile object that would 
normally traverse it, would exceed a standard of paragraphs (a)(1) 
through (3) of this section.
    (5) Any construction or alteration on any of the following airports 
and heliports:
    (i) A public use airport listed in the Chart Supplement U.S., Chart 
Supplement Alaska, or Chart Supplement Pacific of the U.S. Government 
Flight Information Publications;
    (ii) A military airport under construction, or an airport under 
construction that will be available for public use;
    (iii) An airport operated by a Federal agency or the DOD; or
    (iv) An airport or heliport with at least one FAA-approved 
instrument approach procedure.
    (b) If a sponsor has an existing meteorological tower with the 
highest point of the structure at least 50 feet AGL up to and including 
200 feet AGL at its site prior to the effective date of a final rule, 
the sponsor must file notice consistent with Sec.  77.7(d).
    (c) No notice is required of the construction or alteration of:
    (1) Any object that will be shielded by existing structures of a 
permanent and substantial nature or by natural terrain or topographic 
features of equal or greater height, and will be located in the 
congested area of a city, town, or settlement where the shielded 
structure will not adversely affect safety in air navigation;
    (2) Any air navigation facility, airport visual approach or landing 
aid, aircraft arresting device, or meteorological device meeting FAA-
approved siting criteria or an appropriate military service siting 
criteria on military airports, the location and height of which are 
fixed by its functional purpose;
    (3) Any construction or alteration for which notice is required by 
any other FAA regulation.
    (4) Any antenna structure of 20 feet or less in height, except one 
that would increase the height of another antenna structure.


Sec.  77.11  [Redesignated as Sec.  77.10]

0
8. Redesignate Sec.  77.11 as Sec.  77.10.
0
9. Revise newly redesignated Sec.  77.10 to read as follows:


Sec.  77.10  Supplemental notice requirements.

    (a) A sponsor must file supplemental notice when requested by the 
FAA:
    (1) Before the start of construction or alteration;
    (2) After completing actual construction or alteration;
    (3) If the proposed construction or alteration is abandoned within 
five days after the project is abandoned;
    (4) If the construction or alteration is dismantled or destroyed, 
the sponsor must submit notice to the FAA within five days after the 
construction or alteration is dismantled or destroyed; or
    (5) If otherwise requested by the FAA.
    (b) The sponsor must submit the supplemental information using FAA 
Form 7460-2, Notice of Actual Construction or Alteration, to be 
received within the time limits specified in the FAA determination. If 
no time limit has been specified, the sponsor must submit the 
supplemental notice of construction to the FAA within five days after 
the structure reaches its greatest height.
0
10. Add new Sec.  77.11 to read as follows:


Sec.  77.11  Additional information.

    If the FAA requests additional information during any part of the 
aeronautical study process, pre- or post-

[[Page 90646]]

any determination, the sponsor must provide that information within 30 
days.
0
11. Add Sec.  77.12 to read as follows:


Sec.  77.12  Conditions and limitations requirements.

    Except for structures that have received an FAA Determination of No 
Hazard to Air Navigation prior to the effective date of a final rule or 
any meteorological tower with the highest point of the structure at 
least 50 feet AGL up to and including 200 feet AGL at its site for 
which construction is complete prior to the effective date of a final 
rule, a sponsor must comply with the conditions and limitations 
contained in its Determination of No Hazard to Air Navigation.
0
12. Amend Sec.  77.15 by revising paragraph (e)(1) to read as follows:


Sec.  77.15  Scope.

* * * * *
    (e) * * *
    (1) Available for public use and is listed in the Chart Supplement 
U.S., Chart Supplement Alaska, or Chart Supplement Pacific of the U.S. 
Government Flight Information Publications; or
* * * * *
0
13. Revise Sec.  77.27 to read as follows:


Sec.  77.27  Initiation of studies.

    The FAA will conduct an aeronautical study when:
    (a) Notice is required under Sec.  77.9 and has been received; or
    (b) The FAA determines a study is necessary. All other Notices 
filed by the public outside of these parameters will be screened within 
the automated OE/AAA system and, if appropriate, provided an electronic 
letter response that indicates that no notice is required for the said 
proposal or alteration, and thus the FAA has no objections to the 
proposal at this time.
0
14. Amend Sec.  77.29 by revising paragraph (b) to read as follows:


Sec.  77.29  Evaluating aeronautical effect.

* * * * *
    (b) If a sponsor withdraws the proposed construction or alteration 
or revises it so that it is no longer identified as an obstruction, or 
if no further aeronautical study is necessary, the FAA may terminate 
the study.
0
15. Amend Sec.  77.31 by revising paragraph (d)(4) to read as follows:


Sec.  77.31  Determinations.

* * * * *
    (d) * * *
    (4) Marking and lighting requirements, as appropriate.
* * * * *
0
16. Add Sec.  77.32 to read as follows:


Sec.  77.32  Marking and lighting requirements.

    A sponsor may request a modification or deviation from the marking 
and lighting requirements in a determination by submitting FAA Form 
7460-1, Notice of Proposed Construction or Alteration.
0
17. Revise Sec.  77.33 to read as follows:


Sec.  77.33  Effective period of determinations.

    (a) The effective date of a determination not subject to 
discretionary review under Sec.  77.37(b) is the date of issuance. The 
effective date of all other determinations for a proposed or existing 
structure is 40 days from the date of issuance, provided a valid 
petition for review has not been received by the FAA. If a valid 
petition for review is filed, the determination will not become final 
pending disposition of the petition.
    (b) Except as provided in paragraphs (c) and (d) of this section, 
unless extended, revised, or terminated, each Determination of No 
Hazard to Air Navigation issued under this subpart expires 18 months 
after the effective date of the determination, or on the date the 
proposed construction or alteration is abandoned, whichever is earlier.
    (c) Unless extended, revised, or terminated, each Determination of 
No Hazard to Air Navigation issued under this subpart regarding a 
proposed permanent wind energy system, including an airborne wind 
energy system and associated meteorological towers, expires 36 months 
after the effective date of the determination or on the date the 
proposed construction or alteration is abandoned, whichever is earlier. 
A meteorological tower is associated with a wind energy system when it 
is included in a wind energy systems project and is intended to be 
permanent. A meteorological tower is permanent when it is intended to 
remain in place for the duration of its lifecycle.
    (d) A Determination of Hazard to Air Navigation has no expiration 
date.
0
18. Amend Sec.  77.35 by revising the introductory text of paragraph 
(a), and paragraphs (c)(1) through (3) to read as follows:


Sec.  77.35  Extensions, terminations, revisions, and corrections.

    (a) A sponsor may petition the FAA to revise or reconsider the 
determination based on new facts or to extend the effective period of 
the determination, provided that:
* * * * *
    (c) * * *
    (1) The sponsor submits evidence that an application for a 
construction permit/license was filed with the FCC for the associated 
site within six months of issuance of the determination; and
    (2) The sponsor submits evidence that additional time is warranted 
because of FCC requirements; and
    (3) Where the FCC issues a construction permit, a final 
Determination of No Hazard to Air Navigation is effective until the 
date prescribed by the FCC for completion of the construction. If a 
sponsor needs to extend the original FCC completion date, they must 
also request an extension of the FAA determination.
* * * * *
0
19. Revise Sec.  77.37 to read as follows:


Sec.  77.37  General.

    (a) A petition for a discretionary review of a determination, 
revision, or extension of a determination issued by the FAA may be made 
by:
    (1) The sponsor;
    (2) Any person that provided a substantive aeronautical comment on 
a proposal in an aeronautical study;
    (3) Any person that provided a substantive aeronautical comment on 
the proposal but was not given an opportunity to state it.
    (b) A petition for discretionary review for a Determination of No 
Hazard that is issued for a temporary structure, marking and lighting 
requirements, or when a proposed structure or alteration does not 
exceed obstruction standards contained in subpart C of this part may 
not be filed by any person.

    Issued under authority provided by 49 U.S.C. 106(f), 44701(a)(5) 
and 44718 in Washington, DC.
Alyce Hood-Fleming,
Vice President, Mission Support Services, Air Traffic Organization.
[FR Doc. 2024-26741 Filed 11-15-24; 8:45 am]
BILLING CODE 4910-13-P`