[Federal Register Volume 88, Number 199 (Tuesday, October 17, 2023)]
[Rules and Regulations]
[Pages 71468-71478]
[FR Doc No: 2023-22710]

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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Parts 43 and 91

[Docket No. FAA-2023-1836; Amdt. Nos. 43-53 and 91-371]
RIN 2120-AL70

Inclusion of Additional Automatic Dependent Surveillance-
Broadcast (ADS-B) Out Technical Standard Orders; Incorporation by
Reference

AGENCY: Federal Aviation Administration (FAA), U.S. Department of
Transportation (DOT).

ACTION: Direct final rule; request for comments.

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SUMMARY: This rulemaking amends the Automatic Dependent Surveillance-
Broadcast (ADS-B) Out requirements to allow aircraft meeting the
performance requirements in Technical Standard Order (TSO)-C166c
(Extended Squitter Automatic Dependent Surveillance-Broadcast (ADS-B)
and Traffic Information Service-Broadcast (TIS-B) Equipment Operating
on the Radio Frequency of 1090 Megahertz (MHz)), or TSO-C154d,
(Universal Access Transceiver (UAT) ADS-B Equipment Operating on the
Radio Frequency of 978 Megahertz (MHz)) to meet the regulations.
Aircraft equipped with

ADS-B Out that meets the performance requirements of either TSO-C166c
or TSO-C154d will provide additional information to pilots and air
traffic control, including weather information, spectrum monitoring,
and airspeed. They will also enable new wake turbulence applications,
enhance weather forecasting, and enable or enhance ADS-B In
applications such as Flight Interval Management.

DATES: This direct final rule is effective December 18, 2023.
    Send comments on or before November 16, 2023. If the FAA receives
an adverse comment, the FAA will advise the public by publishing a
document in the Federal Register before the effective date of this
direct final rule. That document may withdraw the direct final rule in
whole or in part.
    Incorporation by reference: The incorporation by reference of
certain publications listed in this rule is approved by the Director of
the Office of the Federal Register as of December 18, 2023. The
incorporation by reference of certain other publications listed in this
rule was approved by the Director of the Office of the Federal Register
as of August 11, 2010.

ADDRESSES: Send comments identified by docket number FAA-2023-1836
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.
     Fax: Fax comments to Docket Operations at<PHONE_NUMBER>.
    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 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: Juan Sebastian Yanguas, Airspace Rules
& Regulations, AJV-P21, Federal Aviation Administration, 800
Independence Avenue SW, Washington, DC 20591; telephone<PHONE_NUMBER>;
email [email protected].

SUPPLEMENTARY INFORMATION:

List of Abbreviations and Acronyms Frequently Used in This Document

ADS-B--Automatic Dependent Surveillance-Broadcast
ATC--Air Traffic Control
ICAO--International Civil Aviation Organization
MHz--Megahertz
MOPS--Minimum Operating Performance Standards
NTSB--National Transportation Safety Board
TCAS--Traffic Collision Avoidance System
TIS-B--Traffic Information Service-Broadcast
TSO--Technical Standard Order
UAT--Universal Access Transceiver

I. Executive Summary

    As of January 1, 2020, Federal Aviation Administration (FAA)
regulations, codified in title 14 Code of Federal Regulations (14 CFR),
Sec. Sec.  91.225 and 91.227, require aircraft to equip with Automatic
Dependent Surveillance-Broadcast (ADS-B) Out to operate in expressly
identified airspace areas.\1\ ADS-B Out equipment must meet the
performance requirements in Sec.  91.227 along with those in Technical
Standard Orders (TSO)-C166b or TSO-C154c. This rulemaking revises
Sec. Sec.  91.225 and 91.227 to allow aircraft with equipment that
meets the performance requirements in the new TSOs, TSO-C166c and TSO-
C154d, to also operate in compliance with the regulations.
Specifically, to allow use of these new TSOs, the FAA is incorporating
by reference TSO-C166c, TSO-C154d, section 2 of RTCA DO-260C, RTCA DO-
260C Change 1, and section 2 of RTCA DO-282C into 14 CFR 91.225 and
91.227. Brief summaries of each document being incorporated by
reference can be found in section IV.B. of this preamble. These new
performance requirements enable new wake turbulence applications,
incorporate functionality for high-altitude and high-velocity vehicles,
and enhance weather forecasting. The addition of TSO-C166c and TSO-
C154d to the list of permitted TSOs will not negatively affect current
users because TSO-C166b and TSO-C154c will remain as acceptable
performance requirements.
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    \1\ Section 91.225(h), as redesignated in this rule, requires
unmanned aircraft (UA) to equip with ADS-B Out and broadcast when
they are operating under a flight plan and in two-way radio
communication with air traffic control (ATC). The ADS-B Out
equipment must meet the performance requirements in Sec.  91.227
along with those in TSO-C166b or TSO-C154c. Section 91.225(h), as
redesignated in this rule, is updated to include the two new TSOs.
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    This rulemaking also makes minor changes to other regulatory
sections of part 91. It revises Sec.  91.215 to remove the requirement
that transponders reply to intermode interrogations, as International
Civil Aviation Organization (ICAO) prohibited those replies in ICAO
Annex 10 Volume IV Standards and Recommended Practices and new
transponder certifications do not include the capability to reply to
intermode interrogations. This rulemaking also removes the requirement
in part 43, appendix F, to verify response to an intermode
interrogation.

II. Direct Final Rule

    An agency typically uses direct final rulemaking when it
anticipates that a proposed rule is unnecessary as the rule is
considered noncontroversial.\2\ The FAA has determined that this rule
is suitable for direct final rulemaking as the rule provides an
additional means of compliance with ADS-B Out rule requirements
developed in conjunction with new industry standards. This amendment
will not impose any additional burden on operators whose aircraft are
currently equipped with ADS-B Out equipment meeting the performance
requirements of TSO-C166b or TSO-C154c. Additionally, this change will
increase the ADS-B Out rule compliance options with additional
collateral benefits such as new wake turbulence applications, increased
functionality for high-altitude and high-velocity vehicles, and
enhanced weather forecasting. Moreover, the FAA previously published
the TSOs being incorporated by reference in this direct final rule for
public comment and addressed the comments received.\3\ Any remaining
changes adopted by this rulemaking are technical, clarifying, or
conforming with current legal interpretations or international
requirements. As such, the FAA has determined that this rule is
suitable for direct final rulemaking as these changes are
noncontroversial.
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    \2\ 14 CFR 11.13.
    \3\ The published TSOs and the adjudication of all public
comments received for TSO-C166c and TSO-C154d can be found alongside
each TSO in the FAA Dynamic Regulatory System (refer to https://drs.faa.gov).
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    The FAA is providing notice and seeking comment prior to
effectuating changes to the regulation.\4\ If the FAA

receives an adverse comment during the comment period, the FAA will
advise the public by publishing a document in the Federal Register
before the effective date of the direct final rule. This document may
withdraw the direct final rule in whole or in part. If the FAA
withdraws a direct final rule because of an adverse comment, the FAA
may incorporate the commenter's recommendation into another direct
final rule or may publish a notice of proposed rulemaking (NPRM).\5\
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    \4\ See Adoption of Recommendations, 60 FR 43109, 43110-43111
(Aug. 18, 1995) (describing Administrative Conference of the United
States, Recommendation 95-4, Procedures for Noncontroversial and
Expedited Rulemaking).
    \5\ 14 CFR 11.31(c).
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    For purposes of this direct final rule, an adverse comment is one
that explains (1) why the rule is inappropriate, including challenges
to the rule's underlying premise or approach; or (2) why the direct
final rule will be ineffective or unacceptable without a change.\6\ In
determining whether an adverse comment necessitates withdrawal of this
direct final rule, the FAA will consider whether the comment raises an
issue serious enough to warrant a substantive response had it been
submitted in response to publication of an NPRM. A comment recommending
additional provisions to the rule will not be considered adverse unless
the comment explains how this direct final rule would be ineffective
without the added provisions.\7\
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    \6\ 14 CFR 11.31(a).
    \7\ 14 CFR 11.31(a)(1).
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    Under the direct final rule process, the FAA does not consider a
comment to be adverse if that comment recommends an amendment to a
different regulation beyond the regulation(s) in the direct final rule
at issue. The FAA also does not consider a frivolous or insubstantial
comment to be adverse.\8\
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    \8\ 14 CFR 11.31(a)(1) and (2).
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    If the FAA receives no adverse comments, the FAA will publish a
confirmation notification in the Federal Register, generally within 15
days after the comment period closes. The confirmation notification
announces the effective date of the rule.\9\
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    \9\ 14 CFR 11.31(b).
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III. Authority for This Rulemaking

    The FAA's authority to issue rules on aviation safety is found in
title 49 of the United States Code (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 promulgated under the authority described in
subtitle VII, part A, subpart I, section 40103 (Sovereignty and use of
airspace), and subpart III, section 44701 (General requirements). Under
section 40103, the FAA is charged with prescribing regulations on the
flight of aircraft (including regulations on safe altitudes) for
navigating, protecting, and identifying aircraft, and the efficient use
of the navigable airspace. Under section 44701, the FAA is charged with
promoting safe flight of civil aircraft in air commerce by prescribing
regulations for practices, methods, and procedures the Administrator
finds necessary for safety in air commerce.
    This regulatory action is within the scope of both sections 40103
and 44701 because it prescribes aircraft performance requirements to
meet advanced surveillance needs to accommodate increases in national
airspace system operations. As more aircraft operate within United
States (U.S.) airspace, the FAA needs improved surveillance performance
to accommodate the increased traffic safely and efficiently.

IV. Discussion of the Direct Final Rule

    Effective January 1, 2020, 14 CFR 91.225 requires aircraft
operators to comply with Sec. Sec.  91.225 and 91.227 when the aircraft
is operated in designated classes of airspace (whereas unmanned
aircraft must comply with Sec.  91.225(h), as redesignated by this
rule, when in two-way radio communication with air traffic control
(ATC) and operating under a flight plan). To comply, the ADS-B Out
equipment must meet the performance requirements of Sec.  91.227 and
either TSO-C166b or TSO-C154c.\10\ Moreover, TSO-C166b and TSO-C154c
reference and require compliance with RTCA DO-260B or RTCA DO-282B,
respectively, which are minimum operational performance standards
(MOPS).
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    \10\ The following documents were incorporated by reference into
14 CFR 91.225 and 91.227 as of August 11, 2010 by the final rule,
Automatic Dependent Surveillance-Broadcast (ADS-B) Out Performance
Requirements To Support Air Traffic Control (ATC) Service, 75 FR
30159 (May 28, 2011):
    Technical Standard Order (TSO)-C166b, Extended Squitter
Automatic Dependent Surveillance-Broadcast (ADS-B) and Traffic
Information Service-Broadcast (TIS-B) Equipment Operating on the
Radio Frequency of 1090 Megahertz (MHz) (Dec. 2, 2009);
    TSO-C154c, Universal Access Transceiver (UAT) Automatic
Dependent Surveillance-Broadcast (ADS-B) Equipment Operating on the
Frequency of 978 MHz (Dec. 2, 2009);
    Section 2, Equipment Performance Requirements and Test
Procedures, of RTCA DO-260B, Minimum Operational Performance
Standards for 1090 MHz Extended Squitter Automatic Dependent
Surveillance-Broadcast (ADS-B) and Traffic Information Services-
Broadcast (TIS-B), December 2, 2009 (referenced in TSO-C166b); and
    Section 2, Equipment Performance Requirements and Test
Procedures, of RTCA DO-282B, Minimum Operational Performance
Standards for Universal Access Transceiver (UAT) Automatic Dependent
Surveillance-Broadcast (ADS-B), December 2, 2009 (referenced in TSO-
C154c).
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    Specifically, Sec.  91.225 states no person may operate an aircraft
in Class A airspace unless the aircraft has equipment installed that
meets the performance requirements in TSO-C166b and Sec.  91.227.
Additionally, no person may operate an aircraft below 18,000 feet mean
sea level and in certain airspace described in the regulation unless
the aircraft meets either the performance requirements in Sec.  91.227
and either TSO-C166b or TSO-C154c.
    A TSO is a minimum performance standard for specified materials,
parts, and appliances used on civil aircraft. These standards provide
industry with the minimum requirements they must meet to certify an
ADS-B Out system. The FAA may recognize certain TSOs as a means of
compliance with regulatory requirements, or the regulation may
explicitly incorporate the TSO requirements. For Sec. Sec.  91.225 and
91.227, the FAA has specifically incorporated the TSOs into the
regulations. This process ensures a harmonized approach for equipment
functionality across equipment manufacturers.
    Currently, aircraft with equipment that meet the performance
requirements in TSO-C166b or TSO-C154c are in compliance with the
regulations. This rulemaking revises Sec. Sec.  91.225 and 91.227 to
include the use of equipment compliant with TSO-C166c (Extended
Squitter Automatic Dependent Surveillance-Broadcast (ADS-B) and Traffic
Information Service-Broadcast (TIS-B) Equipment Operating on the Radio
Frequency of 1090 Megahertz (MHz)) or TSO-C154d (Universal Access
Transceiver (UAT) Automatic Dependent Surveillance-Broadcast (ADS-B)
Equipment Operating on the Radio Frequency of 978 Megahertz (MHz)) as
options to meet the ADS-B Out regulations. These new TSOs increase
information available (e.g., weather information or spectrum
monitoring); enable new wake turbulence applications; incorporate
functionality for high-altitude and high-velocity vehicles; and enhance
weather forecasting. They also enable and enhance ADS-B In applications
such as Flight Interval Management. These additions will not negatively
affect current users, as there is no mandate for users to change from
existing ADS-B Out rule-compliant equipment to meet the performance
requirements in TSO-C166c or TSO-C154d. Persons using equipment meeting
the performance requirements in either TSO-C166b or TSO-C154c may
continue to use that

equipment after the adoption of this rule.
    This rulemaking also revises Sec. Sec.  91.225 and 91.227 to
clearly associate each Technical Standard Order with its associated
RTCA document. While Section 2 of RTCA DO-260B and Section 2 of RTCA
DO-282B were previously incorporated by reference into Sec. Sec.
91.225 and 91.227, they were not clearly associated with the TSOs to
which they related. With the addition of two new TSOs and three new
RTCA documents, it is important each TSO be clearly associated with its
referenced RTCA document(s).

A. Addition of TSO-C166c and TSO-C154d Performance Standards

    TSO-C166c, which is a subject of this rulemaking, is largely based
on RTCA's Minimum Operating Performance Standards (MOPS) for ADS-B Out
systems. RTCA is an independent standards development organization
comprised of representatives from industry, government, associations,
and academia. Representatives from these entities collaborated on the
development of an updated standards document for ADS-B Out systems
titled RTCA DO-260C, Minimum Operational Performance Standards for 1090
MHz Extended Squitter Automatic Dependent Surveillance-Broadcast (ADS-
B) and Traffic Information Services--Broadcast (TIS-B). The same
committee subsequently published RTCA DO-260C Change 1 as a
supplemental document to correct errors and add clarifications. RTCA
made both RTCA DO-260C and RTCA DO-260C Change 1 available to the
public through the RTCA website, and the responsible committee
adjudicated all comments received.
    Specifically, the FAA requires compliance with Section 2 of RTCA
DO-260C as modified by Change 1 as part of TSO-C166c. Section 2
establishes equipment performance requirements for 1090 MHz ADS-B
systems. Compliance with the TSO, including Section 2 of RTCA DO-260C
as modified by Change 1, allows industry to show the FAA that their
system is designed and manufactured as required by FAA regulations.
    RTCA DO-260C as modified by Change 1, updates the previous RTCA DO-
260B performance standard to provide additional capabilities enhancing
areas such as safety, equipment performance, airspace efficiency, and
data reporting. The substantive changes from the previous MOPS include:
     Changes to support ICAO requirements that Autonomous
Distress Tracking automatically provide position information at least
once per minute when in distress. Although current Sec.  91.227(c)
already requires the position information, the RTCA revision provides a
means to initiate broadcast announcing that the aircraft is in
distress.
     Additional elements in ADS-B Out messages, including wind
and temperature data, to support more precise spacing of aircraft by
air traffic control (ATC). In addition, the avionics will be able to
support capability for ground radars to extract Flight Interval
Management data from the aircraft.
     The broadcast of aircraft-derived weather data for
applications such as Flight Interval Management, wake vortex avoidance
and surfing, hazardous weather detection and avoidance, and aviation
weather forecasting.
     The broadcast of pilot-observed weather during flight,
including temperature, wind, turbulence, and hazardous weather
information.
     The broadcast of an unmanned aircraft system (UAS)/
Remotely Piloted Aircraft System (RPAS) lost link condition. In this
condition, the UAS/RPAS may broadcast its contingency plan, identifying
the course of action the UAS/RPAS is following.
     Increased the reporting range of altitude and velocity to
support commercial space and hypersonic aircraft operations.
     Inclusion of new capabilities for Airborne Collision
Avoidance System (ACAS)-X, Detect and Avoid (DAA), as well as future
Collision Avoidance Systems (CAS). The new capabilities include
expanded information-laying framework for future passive CAS and
alternate coordination techniques.
     Improved Geometric Altitude reporting by increasing the
reportable difference between geometric and barometric altitude when
information for both is available. Additionally, minimized the
reporting of no integrity by expanding the Navigation Integrity
Category (NIC) reporting when solely geometric altitude is available.
     Provisions for Phase Overlay (PO) techniques enhancing
future capacity and efficiency of the 1090 MHz frequency. PO allows for
transmission of additional data within existing ADS-B Out messages
without the need for additional messages.
     Enhanced requirements for selection of transmission of
airborne or surface message formats for aircraft without an automatic
means of determining on-the-ground status (e.g., a landing gear weight
on wheels switch).
     The broadcast of Interrogation/Reply Monitor data,
including measurements of transponder interrogation and reply rate
activity.
     Improved emitter category classifications and descriptions
to prevent misuse by future applications.
     Transmission of transponder antenna offset information
improving tracking of aircraft and vehicles operating on the airport
surface by the airport surface detection systems.
    TSO-C154d, which is also the subject of this rulemaking, is largely
based on RTCA DO-282C, Minimum Operational Performance Standards (MOPS)
for Universal Access Transceiver (UAT) Automatic Dependent
Surveillance-Broadcast (ADS-B). RTCA made RTCA DO-282C available to the
public through the RTCA website, and the responsible committee
adjudicated all comments received.
    Specifically, the FAA requires compliance with Section 2 of RTCA
DO-282C as part of TSO-C154d. Section 2 establishes equipment
performance requirements for UAT ADS-B systems. Compliance with the
TSO, including Section 2 of RTCA DO-282C, allows industry to show the
FAA that their system is designed and manufactured as required by FAA
regulations.
    RTCA DO-282C updates the previous RTCA DO-282B performance standard
to provide additional capabilities enhancing areas such as safety,
equipment performance, airspace efficiency, and data reporting. The
substantive changes to the previous performance standard include:
     Changes to support ICAO requirements that Autonomous
Distress Tracking automatically provide position information at least
once per minute when in distress. Although current Sec.  91.227(c)
already requires the position information, the RTCA revision provides a
means to initiate broadcast announcing that the aircraft is in
distress.
     Additional elements in ADS-B Out messages, including wind
and temperature data, to support more precise spacing of aircraft by
ATC. In addition, the avionics will be able to support capability for
ground radars to extract Flight Interval Management data from the
aircraft.
     The broadcast of aircraft-derived weather data for
applications such as Flight Interval Management, wake vortex avoidance
and surfing, hazardous weather detection and avoidance, and aviation
weather forecasting.
     The broadcast of pilot-observed weather during flight,
including temperature, wind, turbulence, and hazardous weather
information.

     The broadcast of a UAS/RPAS lost link condition. In this
condition, the UAS/RPAS may broadcast its contingency plan, identifying
the course of action the UAS/RPAS is following.
     Increased the reporting range of altitude and velocity to
support commercial space and hypersonic aircraft operations.
     Enhanced requirements for selection of transmission of
airborne or surface message formats for aircraft without an automatic
means of determining on-the-ground status (e.g., a landing gear weight
on wheels switch).
     Improved emitter category classifications and descriptions
to prevent misuse by future applications.
    This rule will allow aircraft with equipment compliant with the
performance requirements of TSO-C166c and RTCA DO-260C as modified by
Change 1, and TSO-C154d and RTCA DO-282C to operate in the airspace
areas identified in Sec.  91.225. Importantly, this rulemaking does not
impact any operators currently in compliance with Sec. Sec.  91.225 and
91.227.
    Including TSO-C166c and TSO-C154d in Sec. Sec.  91.225 and 91.227
allows the use of updated technology to meet ADS-B Out requirements and
enables improvements in the ADS-B environment, such as the ability to
transmit additional data; and to include ADS-B Out for high-altitude
and high-velocity vehicles.

B. Incorporation by Reference

    Incorporation by reference (IBR) is a mechanism that allows Federal
agencies to comply with the requirements of the Administrative
Procedure Act to publish rules in the Federal Register and the CFR by
referring to material published elsewhere.\11\ Material that is
incorporated by reference has the same legal status as if it were
published in full in the Federal Register and the CFR. The standards
referenced in this rule include technical information and
specifications for equipment and capabilities required to meet FAA ADS-
B Out requirements.
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    \11\ 5 U.S.C. 552(a).
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    The standards referenced in Sec. Sec.  91.225 and 91.227 of this
rule are incorporated by reference with the approval of the Director of
the Office of the Federal Register under 5 U.S.C. 552(a) and 1 CFR part
51. In accordance with 5 U.S.C. 552(a) and 1 CFR part 51,\12\ all
approved materials are available for inspection at the FAA's Office of
Rulemaking, 800 Independence Avenue SW, Washington, DC 20590 (telephone
(202) 267-9677). This material is also available from the sources
indicated in paragraphs (i)(1) and (2) of Sec.  91.225, as redesignated
by this rule, and paragraphs (g)(1) and (2) of Sec.  91.227 and as
follows:
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    \12\ 5 U.S.C. 552(a) requires that matter incorporated by
reference be ``reasonably available'' as a condition of its
eligibility. Further, 1 CFR 51.5(b)(2) requires that agencies
seeking to incorporate material by reference discuss in the preamble
of the final rule the ways that the material it is incorporating by
reference is reasonably available to interested parties and how
interested parties can obtain the material.
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    1. Copies of the following Technical Standard Orders (TSOs) may be
obtained from the U.S. Department of Transportation, Subsequent
Distribution Office, DOT Warehouse M30, Ardmore East Business Center,
3341 Q 75th Avenue, Landover, MD 20785; telephone<PHONE_NUMBER>.
Copies are also available on the FAA's website at www.faa.gov/aircraft/air_cert/design_approvals/tso/. Select the link ``Search Technical
Standard Orders.''
a. TSO-C166c, Extended Squitter Automatic Dependent Surveillance-
Broadcast (ADS-B) and Traffic Information Service--Broadcast (TIS-B)
Equipment Operating on the Radio Frequency of 1090 Megahertz (MHz)
(March 10, 2023);
    i. This TSO contains the minimum performance standards that 1090
MHz ADS-B and TIS-B equipment must meet for approval and identification
with the applicable TSO marking.
b. TSO-C154d, Universal Access Transceiver (UAT) Automatic Dependent
Surveillance-Broadcast (ADS-B) Equipment Operating on the Radio
Frequency of 978 Megahertz (MHz) (March 10, 2023).
    i. This TSO contains the minimum performance standards that UAT
ADS-B equipment and/or UAT diplexers must meet for approval and
identification with the applicable TSO marking.
    2. Copies of the following documents may be obtained from RTCA,
Inc., 1150 18th St. NW, Suite 910, Washington, DC 20036, telephone
(202) 833-9339. Copies are also available on the RTCA Inc. Website at
https://www.rtca.org/products.
    a. RTCA DO-260C, Minimum Operational Performance Standards for 1090
MHz Extended Squitter Automatic Dependent Surveillance-Broadcast (ADS-
B) and Traffic Information Services-Broadcast (TIS-B), Section 2,
Equipment Performance Requirements and Test Procedures, December 17,
2020; and Minimum Operational Performance Standards for 1090 MHz
Extended Squitter Automatic Dependent Surveillance-Broadcast (ADS-B)
and Traffic Information Services-Broadcast (TIS-B) Change 1, January
25, 2022 (referenced in TSO-C166c);
    i. Section 2 of RTCA DO-260C contains the equipment performance
requirements and test procedures for 1090 MHz ADS-B and TIS-B
equipment.
    ii. DO-260C Change 1 contains updates, corrections, and additional
material to support the implementation of RTCA DO-260C.
    b. RTCA DO-282C, Minimum Operational Performance Standards (MOPS)
for Universal Access Transceiver (UAT) Automatic Dependent
Surveillance-Broadcast (ADS B), Section 2, Equipment Performance
Requirements and Test Procedures, June 23, 2022 (referenced in TSO-
C154d).
    i. Section 2 of RTCA DO-282C contains the equipment performance
requirements and test procedures for UAT ADS-B equipment.
    The following standards appear in the amendatory text of this
document and were previously approved for the locations in which they
appear: TSO-C166b, TSO-C154c, RTCA DO-260B, Section 2, and RTCA DO-
282B, Section 2.

C. Advisory Circulars Updated as Part of This Rulemaking

    As part of this rulemaking, the FAA is updating FAA Advisory
Circular (AC) 90-114B, Automatic Dependent Surveillance--Broadcast
Operations, to modify references to the TSOs listed for ADS-B Out
equipment that complies with title 14 of the Code of Federal
Regulations part 91, Sec. Sec.  91.225 and 91.227.

D. Miscellaneous Amendments

    This rule also includes a number of minor miscellaneous changes to
Sec. Sec.  91.215, 91.225, and 91.227 to incorporate updated ICAO
requirements, clarify ambiguities identified in past requests for legal
interpretations, clarify vague requirements, correct previous
typographical errors, change a physical location address, and ensure
valid website links.
    The FAA amends Sec. Sec.  91.215 and 91.227 by replacing the term
``Mode 3/A'' with ``Mode A'' in both Sec.  91.215(b) and Sec.
91.227(d)(7). Mode A is a civilian mode intended to elicit transponder
replies for identity and surveillance. Mode 3 is a military mode also
used to elicit transponder replies for identity and surveillance. Mode
3 contains all the functionality of Mode A along with additional
military-specific capability. For this reason, the military community

often uses the term ``Mode 3/A,'' a term the civil community does not
widely use. This editorial change will properly emphasize that the
regulation requires the Mode A functionality and not the military-
specific functionality of Mode 3. In addition, using the term Mode A is
consistent with the language used by ICAO and RTCA documents.
    This rule also removes the requirement in Sec.  91.215(b) to reply
to intermode interrogations, and removes the requirement in part 43,
appendix F, to verify response to an intermode interrogation.
Currently, Sec.  91.215(b) requires aircraft equipped with a Mode S
capability to reply ``to Mode 3/A interrogations with the code
specified by ATC and intermode and Mode S interrogations in accordance
with the applicable provisions specified in TSO C-112.'' Additionally,
part 43, appendix F, paragraph (h), requires verification that an ATC
transponder respond to an Air Traffic Control Radar Beacon System
(ATCRBS)/Mode S all-call interrogation. ICAO Annex 10 Volume IV
establishes two types of intermode interrogations: Mode A/C/S all-call
and Mode A/C-only all-call. Mode A/C/S all-call interrogations were
designed to produce a Mode S reply in Mode S capable transponders and a
Mode A or C reply in non-Mode S capable transponders. Mode A/C-only
all-call interrogations were designed to not produce a reply by Mode S
capable transponders and to produce a Mode A or C reply in non-Mode S
transponders. Therefore, the only type of intermode interrogation that
a Mode S transponder was intended to reply to per Sec.  91.215(b) was a
Mode A/C/S all-call interrogation. However, ICAO now prohibits replies
to Mode A/C/S all-call interrogations in new equipment
certifications.\13\ Mode A/C/S all-call interrogations were never
implemented in U.S. ground radar systems, but the inclusion of this
capability within existing transponders led to an increase in what is
known as False Replies Un-synchronized In Time (FRUIT). Radio Frequency
(RF) propagation effects often result in a Mode A/C-only all-call
interrogation appearing to be a Mode A/C/S all-call interrogation at
the receiver of a transponder. When a Mode S transponder decodes a Mode
A/C/S all-call interrogation, an undesired reply is transmitted by the
transponder, resulting in the increase of FRUIT. Removal of the
requirement to reply to intermode interrogations ensures compliance
with ICAO requirements and reduces the number of unsolicited replies,
thus reducing 1090 MHz spectrum congestion. RTCA DO-181F, referenced by
TSO-C112f, also prohibits Mode S transponders from responding to Mode
A/C/S all-call interrogations. Equipment certified to TSO-C112 versions
prior to TSO-C112f will retain the capability to reply to Mode A/C/S
all-call interrogations and will continue to be compliant with Sec.
91.215(b).
---------------------------------------------------------------------------

    \13\ See ICAO Annex 10 Vol IV sec. <IP_ADDRESS>.<IP_ADDRESS>.
---------------------------------------------------------------------------

    Accordingly, this rule removes the requirement in 14 CFR part 43,
appendix F, paragraph (h), to verify response to an intermode
interrogation, specifically the ATCRBS/Mode S all-call formats (1.6
microsecond P4 pulse), which is another name for the Mode A/C/S all-
call interrogation. This conforming amendment aligns the inspection and
test requirements in part 43 with the ICAO prohibition to reply to Mode
A/C/S all-call interrogations.
    This rule also amends part 43, appendix F, paragraph (j), which
requires verification that the Mode S transponder generates a correct
squitter approximately once per second, by clarifying the squitter is
an acquisition squitter.
    Additionally, the FAA amends Sec.  91.225(e) by adding the term
``engine-driven'' before ``electrical system.'' This amendment will
clarify that the relief described in Sec.  91.225 applies to aircraft
whose electrical system was not originally or subsequently certificated
to be powered by the aircraft's engine. This rephrasing is consistent
with the phrase used in Sec.  91.215(b)(3) to describe the same
category of aircraft. The difference in language has led to confusion
among regulated entities, as evidenced by the FAA's legal
interpretation sent to David Schober on January 5, 2017.\14\ Mr.
Schober requested clarification on the applicability of Sec.  91.225(e)
to aircraft that had not been originally certificated with an
electrical system but which have subsequently had batteries or electric
starters installed. The FAA determined that the intent of the language
was to cover the same types of aircraft as in the transponder
regulation. This amendment will make it clear that both regulatory
provisions refer to the same category of aircraft.
---------------------------------------------------------------------------

    \14\ Available at https://www.faa.gov/about/office_org/headquarters_offices/agc/practice_areas/regulations/interpretations.
---------------------------------------------------------------------------

    The FAA is revising the definitions for ``Navigation Accuracy
Category for Position (NACP)'', ``Navigation Accuracy Category for
Velocity (NACV)'', ``Navigation Integrity Category (NIC)'', ``Source
Integrity Level (SIL)'', and ``System Design Assurance (SDA)'' in Sec.
91.227(a) to remove the references to TSO-C166b and TSO-C154c. The FAA
has determined that including references to these standards in the
definitions themselves is unnecessary and could lead to confusion as
more Technical Standard Orders are added to this regulation. The FAA
notes that references to the Technical Standard Orders appear in the
actual regulatory requirements of Sec.  91.227.
    Further, the FAA also amends the way it describes the System Design
Assurance (SDA) reporting requirements in Sec.  91.227(c)(1)(iv) and
the Source Integrity Level (SIL) reporting requirement in Sec.
91.227(c)(1)(v) without changing the underlying substantive requirement
itself. Under the FAA's current regulation, the FAA codified numerical
values used by RTCA to represent probability values. That is, per DO-
260B, an SDA value of 2 represents ``the probability of a position
transmission chain fault causing false or misleading position
information to be transmitted'' to be <=1 x 10-5 per flight
hour. This action revises Sec.  91.227(c)(1)(iv) to require an SDA of
<=1 x 10-5 per flight hour instead of the equivalent RTCA
DO-260B value of 2. A SIL of 3 represents ``the probability of the
reported horizontal position exceeding the radius of containment
(RC) defined by the NIC, without alerting, assuming no
avionics faults'' to be <=1 x 10-7 per flight hour or per
sample. Therefore, Sec.  91.227(c)(1)(v) will require a SIL value of
<=1 x 10-7 per flight hour or per sample instead of the
equivalent RTCA DO-260B value of 3. This change does not alter the
underlying performance requirements. Instead, it codifies the actual
probability requirement rather than the equivalent conversion used by
RTCA DO-260B. This editorial change makes the regulation's performance
requirements clear within the regulation without having to consult RTCA
DO-260B. It also ensures that this performance standard remains
constant in case RTCA revises SDA and SIL.
    Additionally, this rule amends Sec.  91.227(d)(13) to conform to
the FAA's intent that the element indicate that the aircraft has the
capability to receive ADS-B In services, not necessarily that this
capability be installed. The revised regulatory text will replace the
current word ``installed'' with the word ``available.'' After the
amendment's effective date, Sec.  91.227(d)(13) will require ``[a]n
indication of whether ADS-B In capability is available.'' The FAA
became aware of the confusion after John D. Collins' September 20, 2012
letter requesting an interpretation

of Sec.  91.227(d)(13).\15\ Mr. Collins explained that some aircraft
operators use portable ADS-B In receivers without installing the
equipment. By using the word ``installed'' in the regulatory language,
some aircraft operators and installers believed that an aircraft could
not indicate ADS-B In capability if the appropriate equipment was not
physically installed on the aircraft.
---------------------------------------------------------------------------

    \15\ Available at www.faa.gov/about/office_org/headquarters_offices/agc/practice_areas/regulations/interpretations.
---------------------------------------------------------------------------

    Per the preamble to the Automatic Dependent Surveillance-Broadcast
(ADS-B) Out Performance Requirements to Support Air Traffic Control
(ATC) Service published on May 28, 2010,\16\ the ADS-B In capability is
meant to provide ADS-B ground stations with an indication of what, if
any, FAA ADS-B services should be provided to the aircraft. In a legal
interpretation sent to John D. Collins on August 23, 2013, the FAA
explained that the intent was for this message element to indicate that
the aircraft has the capability to receive ADS-B In services, not
necessarily that this capability is installed. Therefore, this change
clarifies that aircraft are to indicate that ADS-B reception capability
is available, even if the system receiving the data is not installed on
the aircraft. The FAA ground stations will provide ADS-B In services to
all eligible aircraft indicating an ADS-B In capability.
---------------------------------------------------------------------------

    \16\ 75 FR 30159.
---------------------------------------------------------------------------

    The FAA also clarifies Sec.  91.227(d)(5) by revising ``TCAS II or
ACAS'' to ``collision avoidance system.'' While the FAA often uses the
term TCAS in various rules and regulations, other nations and ICAO
generally use the term ACAS. For this reason, Sec.  91.227 used the
term ``TCAS II or ACAS'' in an attempt to reduce confusion. Since the
initial publication of Sec.  91.227, the FAA published a new TSO (TSO-
C219) for an additional collision avoidance system: ACAS Xa/Xo. TSO-
C219 was published by the FAA on February 28, 2020.\17\ Additionally,
various other collision avoidance systems are currently in development.
Due to the long-standing confusion with the terminology, RTCA, ICAO,
and international regulators all use the generic term ``collision
avoidance system (CAS).'' This editorial change provides enhanced
clarity but does not alter the existing broadcast requirements.
---------------------------------------------------------------------------

    \17\ Available at https://drs.faa.gov/browse.
---------------------------------------------------------------------------

    Further, the FAA clarifies Sec.  91.227(d)(8) by changing the
required broadcast information from ``an indication of the aircraft's
call sign that is submitted on the flight plan, or the aircraft's
registration number'' to ``an indication of the aircraft identification
that is submitted on the flight plan or used for communicating with
ATC.'' The change will clarify, not alter, the substantive meaning of
the paragraph. On July 27, 2017, the FAA sent an internal request for
legal interpretation of Sec.  91.225(d)(8). Some manufacturers and
operators interpreted the existing language to mean that the aircraft
registration number could be programmed into the aircraft
identification field of the ADS-B avionics and yet a different aircraft
call sign could be filled in the flight plan. The FAA legal
interpretation sent to Jere Hayslett on August 3, 2017, stated that in
the preamble to the final rule, to satisfy Sec.  91.227(d)(8) a pilot
would have to provide the same call sign on their flight plan as they
transmit out using ADS-B to avoid ATC confusion. This amendment makes
clear that the aircraft identification included on the flight plan must
match the aircraft identification transmitted via ADS-B Out.
Furthermore, the change also clarifies that for those aircraft that do
not file a flight plan, the aircraft identification transmitted via
ADS-B Out must match the aircraft identification used for communicating
with ATC and ensures ATC can correlate flight plan information with
information displayed on the radar display.
    In addition, the FAA is undertaking the following purely clerical
changes:
     Corrects typographical errors in Sec. Sec.  91.225(i)(1),
as redesignated by this rule, and 91.227(c) and (g)(1) and (2). These
include removing of extra spaces, correcting capitalizations, and
correcting placement of dash marks.
     Updates website addresses in Sec. Sec.  91.225(i)
introductory text and (i)(1) and (2), as redesignated by this rule, and
91.227(g) introductory text and (g)(1) and (2).
     Updates the RTCA physical address in Sec. Sec.
91.225(i)(2), as redesignated by this rule, and 91.227(g)(2).

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 and Executive Order 13563, as amended by Executive Order
14094 (``Modernizing Regulatory Review''), direct that each Federal
agency shall 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 million or more
(adjusted annually for inflation) in any one year. The current
threshold after adjustment for inflation is $177 million using the most
current (2022) Implicit Price Deflator for the Gross Domestic Product.
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
has benefits that justify its costs; is not significant as defined in
section 3(f)(1) of Executive Order 12866; will not 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. Regulatory Evaluation

    ADS-B enhances safety and efficiency and directly benefits pilots,
controllers, airports, airlines, and the public. This rule enables
additional features of ADS-B Out as an option to meet all ADS-B
requirements by revising Sec. Sec.  91.225 and 91.227. Since this
direct final rule maintains the performance standards by providing
aircraft operators the option, on a voluntary basis, to implement
additional features into the ADS-B equipment, the direct final rule
will not incur any costs to the operators and the public. Revising
Sec.  91.215 adds no new cost to the public because it removes the
requirement to support a capability that has no operational use. By
increasing the information available, enabling new wake turbulence
applications, incorporating functionality for high-altitude and high-
velocity vehicles, and enhancing weather forecasting, this direct final
rule has unquantifiable benefits to aircraft operators.

B. Regulatory Flexibility Determination

    The Regulatory Flexibility Act (RFA), Public Law 96-354, (5 U.S.C.
601-612),

as amended by the Small Business Regulatory Enforcement Fairness Act
(Pub. L. 104-121) and the Small Business Jobs Act (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 and 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.
    Agencies must perform a review to determine whether a rulemaking
would have a significant economic impact on a substantial number of
small entities. If the agency determines that it will, the agency must
prepare a regulatory flexibility analysis as described in the RFA.
However, if an agency determines that a rule is not expected to have a
significant economic impact on a substantial number of small entities,
section 605(b) of the RFA provides that the head of the agency may so
certify, and a regulatory flexibility analysis is not required.
    This direct final rule adds an option for aircraft operators to
incorporate additional features into ADS-B equipment described in
Sec. Sec.  91.225 and 91.227 and allows for the removal of an unused
capability in Sec.  91.215. This direct final rule will not require
additional reporting, recordkeeping, and other compliances for small
businesses.
    Therefore, as provided in section 605(b), the head of the FAA
certifies that this direct final rule does not result in a significant
economic impact on a substantial number of 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
impose no costs on either domestic or international entities and thus
has a neutral trade impact.

D. Unfunded Mandates Assessment

    Title II of the Unfunded Mandates Reform Act of 1995 (Pub. L. 104-
4) requires each Federal agency to prepare a written statement
assessing the effects of any Federal mandate in a proposed or final
agency rule that may result in an expenditure of $100 million or more
(in 1995 dollars) in any one year by State, local, and tribal
governments, in the aggregate, or by the private sector; such a mandate
is deemed to be a ``significant regulatory action.'' The FAA currently
uses an inflation-adjusted value of $177.0 million in lieu of $100
million.
    This rule does not contain such a mandate. Therefore, the
requirements of title II of the Act do not apply.

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. The FAA has determined that
there is no new requirement for information collection associated with
this direct final rule.

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 (SARPs) to the maximum extent practicable. ICAO
plans to update its current SARPs to reflect harmonized changes to both
RTCA and EUROCAE minimum performance standards, as appropriate, for
ADS-B Out operations. The FAA also will continue to work with the
international community to ensure harmonization.

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 has
determined this rulemaking action qualifies for the categorical
exclusion identified in paragraph 5-6.6f for regulations and involves
no extraordinary circumstances.

VI. Executive Order Determinations

A. Executive Order 13132, Federalism

    The FAA has analyzed this direct final rule under the principles
and criteria of Executive Order 13132, Federalism. The agency
determined that this action will 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, does not have
federalism implications.

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

    The FAA analyzed this direct final rule under Executive Order
13211, Actions Concerning Regulations that Significantly Affect Energy
Supply, Distribution, or Use. The agency has determined that this rule
is not a ``significant energy action'' under the Executive order and
the rule is not 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 action under the policies and agency responsibilities of Executive
Order 13609 and has 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 most
helpful comments reference a specific portion of the rule, explain the
reason for any recommended change, and include supporting data. To
ensure the docket does not contain duplicate comments, commenters
should send only one copy of written comments, or if comments are filed
electronically, commenters should submit only one time.
    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 rulemaking. Before acting on this rulemaking,
the FAA will consider all

comments it receives on or before the closing date for comments. The
agency may change this rule 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 www.regulations.gov, as described in the system
of records notice (DOT/ALL-14 FDMS), which can be reviewed at
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 direct final rule 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 direct final rule, 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 direct
final rule. 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 which is not specifically designated
as CBI will be placed in the public docket for this rulemaking.

C. Electronic Access and Filing

    A copy of this direct final rule, all comments received, any
confirmation document, and all background material may be viewed online
at https://www.regulations.gov using the docket number listed above. A
copy of this direct final 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<PHONE_NUMBER>.
Interested persons must identify the docket or amendment number of this
rulemaking.
    All documents the FAA considered in developing this rule, including
economic analyses and technical reports, may be accessed in the
electronic docket for this rulemaking.

D. Small Business Regulatory Enforcement Fairness Act

    The Small Business Regulatory Enforcement Fairness Act (SBREFA) of
1996 requires the FAA to comply with small entity requests for
information or advice about compliance with statutes and regulations
within its jurisdiction. A small entity with questions regarding this
document may contact its local FAA official or the person listed under
the FOR FURTHER INFORMATION CONTACT heading at the beginning of the
preamble. To find out more about SBREFA on the internet, visit https://www.faa.gov/regulations_policies/rulemaking/sbre_act/.

List of Subjects

14 CFR Part 43

    Aircraft, Aviation safety, Reporting and recordkeeping
requirements.

14 CFR Part 91

    Air traffic control, Aircraft, Airports, Aviation safety,
Incorporation by reference, Transportation.

The Amendment

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

PART 43--MAINTENANCE, PREVENTIVE MAINTENANCE, REBUILDING, AND
ALTERATION

0
1. The authority citation for part 43 continues to read as follows:

    Authority: 42 U.S.C. 7572; 49 U.S.C. 106(f), 106(g), 40105,
40113, 44701-44702, 44704, 44707, 44709, 44711, 44713, 44715, 45303.

0
2. Amend appendix F to part 43 by revising paragraphs (h) and (j) to
read as follows:

Appendix F to Part 43--ATC Transponder Tests and Inspections

* * * * *
    (h) Mode S All-Call Interrogations: Interrogate the Mode S
transponder with the Mode S-only all-call format UF = 11 and verify
that the correct address and capability are reported in the replies
(downlink format DF = 11).
* * * * *
    (j) Squitter: Verify that the Mode S transponder generates a
correct acquisition squitter approximately once per second.
* * * * *

PART 91--GENERAL OPERATING AND FLIGHT RULES

0
3. The authority citation for part 91 continues to read as follows:

    Authority:  49 U.S.C. 106(f), 106(g), 40101, 40103, 40105,
40113, 40120, 44101, 44111, 44701, 44704, 44709, 44711, 44712,
44715, 44716, 44717, 44722, 46306, 46315, 46316, 46504, 46506-46507,
47122, 47508, 47528-47531, 47534, Pub. L. 114-190, 130 Stat. 615 (49
U.S.C. 44703 note); articles 12 and 29 of the Convention on
International Civil Aviation (61 Stat. 1180), (126 Stat. 11).

0
4. Amend Sec.  91.215 by revising the introductory text of paragraph
(b) to read as follows:

Sec.  91.215  ATC transponder and altitude reporting equipment and use.

* * * * *
    (b) All airspace. Unless otherwise authorized or directed by ATC,
and except as provided in paragraph (e)(1) of this section, no person
may operate an aircraft in the airspace described in paragraphs (b)(1)
through (5) of this section, unless that aircraft is equipped with an
operable coded radar beacon transponder having either Mode A 4096 code
capability, replying to Mode A interrogations with the code specified
by ATC, or a Mode S capability, replying to Mode A interrogations with
the code specified by ATC and Mode S interrogations in accordance with
the applicable provisions specified in TSO-C112, and that aircraft is
equipped with automatic pressure altitude reporting equipment having a
Mode C capability that automatically replies to Mode C interrogations
by transmitting pressure altitude information in 100-foot increments.
The requirements of this paragraph (b) apply to--
* * * * *

0
5. Amend Sec.  91.225 by:
0
a. Revising paragraphs (a)(1), (b), and (e) introductory text.
0
b. Redesignating paragraphs (h) and (i) as set out in the following
redesignation table.

------------------------------------------------------------------------
               Old paragraph                        New paragraph
------------------------------------------------------------------------
paragraph (h).............................  paragraph (i).
paragraph (i).............................  paragraph (h).
------------------------------------------------------------------------

0
c. Revising newly redesignated paragraphs (h)(1)(i) and (i).
    The revisions read as follows:

Sec.  91.225  Automatic Dependent Surveillance-Broadcast (ADS-B) Out
equipment and use.

    (a) * * *

    (1) Meets the performance requirements in-
    (i) TSO-C166b and Section 2 of RTCA DO-260B (as referenced in TSO-
C166b); or
    (ii) TSO-C166c and Section 2 of RTCA DO-260C as modified by DO-
260C--Change 1 (as referenced in TSO-C166c); and
* * * * *
    (b) After January 1, 2020, except as prohibited in paragraph (h)(2)
of this section or unless otherwise authorized by ATC, no person may
operate an aircraft below 18,000 feet MSL and in airspace described in
paragraph (d) of this section unless the aircraft has equipment
installed that--
    (1) Meets the performance requirements in--
    (i) TSO-C166b and Section 2 of RTCA DO-260B (as referenced in TSO-
C166b);
    (ii) TSO-C166c and Section 2 of RTCA DO-260C as modified by DO-
260C--Change 1 (as referenced in TSO-C166c);
    (iii) TSO-C154c and Section 2 of RTCA DO-282B (as referenced in
TSO-C154c); or
    (iv) TSO-C154d and Section 2 of RTCA DO-282C (as referenced in TSO-
C154d);
    (2) Meets the requirements of Sec.  91.227.
* * * * *
    (e) The requirements of paragraph (b) of this section do not apply
to any aircraft that was not originally certificated with an engine-
driven electrical system, or that has not subsequently been certified
with such a system installed, including balloons and gliders. These
aircraft may conduct operations without ADS-B Out in the airspace
specified in paragraph (d)(4) of this section. These aircraft may also
conduct operations in the airspace specified in paragraph (d)(2) of
this section if those operations are conducted--
* * * * *
    (h) * * *
    (1) * * *
    (i) That aircraft has equipment installed that meets the
performance requirements in TSO-C166b (including Section 2 of RTCA DO-
260B, as referenced in TSO-C166b), TSO-C166c (including Section 2 of
RTCA DO-260C as modified by DO-260C--Change 1, as referenced in TSO-
C166c), TSO-C154c (including Section 2 of RTCA DO-282B, as referenced
in TSO-C154c), or TSO-C154d (including Section 2 of RTCA DO-282C, as
referenced in TSO-C154d); and
* * * * *
    (i) The standards required in this section are incorporated by
reference with the approval of the Director of the Office of the
Federal Register under 5 U.S.C. 552(a) and 1 CFR part 51. This
incorporation by reference (IBR) material is available for inspection
at the FAA and the National Archives and Records Administration (NARA).
Contact the FAA at: Office of Rulemaking (ARM-1), 800 Independence
Avenue SW, Washington, DC 20590 (telephone<PHONE_NUMBER>). For
information on the availability of this material at NARA, visit https://www.archives.gov/federal-register/cfr/ibr-locations.html or email
[email protected]. This material is also available from the
following sources in this paragraph (i).
    (1) U.S. Department of Transportation, Subsequent Distribution
Office, DOT Warehouse M30, Ardmore East Business Center, 3341 Q 75th
Avenue, Landover, MD 20785; telephone<PHONE_NUMBER>; website:
www.faa.gov/aircraft/air_cert/design_approvals/tso/ (select the link
``Search Technical Standard Orders'').
    (i) TSO-C166b, Extended Squitter Automatic Dependent Surveillance-
Broadcast (ADS-B) and Traffic Information Service-Broadcast (TIS-B)
Equipment Operating on the Radio Frequency of 1090 Megahertz (MHz),
December 2, 2009.
    (ii) TSO-C166c, Extended Squitter Automatic Dependent Surveillance-
Broadcast (ADS-B) and Traffic Information Service-Broadcast (TIS-B)
Equipment Operating on the Radio Frequency of 1090 Megahertz (MHz),
March 10, 2023.
    (iii) TSO-C154c, Universal Access Transceiver (UAT) Automatic
Dependent Surveillance-Broadcast (ADS-B) Equipment Operating on the
Frequency of 978 MHz, December 2, 2009.
    (iv) TSO-C154d, Universal Access Transceiver (UAT) Automatic
Dependent Surveillance-Broadcast (ADS-B) Equipment Operating on the
Radio Frequency of 978 Megahertz (MHz), March 10, 2023.
    (2) RTCA, Inc., 1150 18th St. NW, Suite 910, Washington, DC 20036;
telephone<PHONE_NUMBER>; website: www.rtca.org/products.
    (i) RTCA DO-260B, Minimum Operational Performance Standards for
1090 MHz Extended Squitter Automatic Dependent Surveillance-Broadcast
(ADS-B) and Traffic Information Services-Broadcast (TIS-B), Section 2,
Equipment Performance Requirements and Test Procedures, December 2,
2009.
    (ii) RTCA DO-260C, Minimum Operational Performance Standards for
1090 MHz Extended Squitter Automatic Dependent Surveillance-Broadcast
(ADS-B) and Traffic Information Services-Broadcast (TIS-B), Section 2,
Equipment Performance Requirements and Test Procedures, December 17,
2020.
    (iii) RTCA DO-260C, Minimum Operational Performance Standards for
1090 MHz Extended Squitter Automatic Dependent Surveillance--Broadcast
(ADS-B) and Traffic Information Services--Broadcast (TIS-B), Change 1,
January 25, 2022.
    (iv) RTCA DO-282B, Minimum Operational Performance Standards for
Universal Access Transceiver (UAT) Automatic Dependent Surveillance-
Broadcast (ADS-B), Section 2, Equipment Performance Requirements and
Test Procedures, December 2, 2009.
    (v) RTCA DO-282C, Minimum Operational Performance Standards (MOPS)
for Universal Access Transceiver (UAT) Automatic Dependent
Surveillance-Broadcast (ADS-B), Section 2, Equipment Performance
Requirements and Test Procedures, June 23, 2022.

0
6. Amend Sec.  91.227 by:
0
a. In paragraph (a), revising definitions for ``Navigation Accuracy
Category for Position (NACP)'', ``Navigation Accuracy
Category for Velocity (NACV)'', ``Navigation Integrity
Category (NIC)'', ``Source Integrity Level (SIL)'', and ``System Design
Assurance (SDA)''; and
0
b. Revising paragraphs (b)(1), (b)(2)(i) and (ii), (c)(1)(iv) and (v),
(d) introductory text, (d)(5) through (8), (11), and (13), and (g).
    The revisions read as follows:

Sec.  91.227  Automatic Dependent Surveillance-Broadcast (ADS-B) Out
equipment performance requirements.

    (a) * * *
    Navigation Accuracy Category for Position (NACP) specifies the
accuracy of a reported aircraft's position.
    Navigation Accuracy Category for Velocity (NACV) specifies the
accuracy of a reported aircraft's velocity.
    Navigation Integrity Category (NIC) specifies an integrity
containment radius around an aircraft's reported position.
* * * * *
    Source Integrity Level (SIL) indicates the probability of the
reported horizontal position exceeding the containment radius defined
by the NIC on a per sample or per hour basis.
    System Design Assurance (SDA) indicates the probability of an
aircraft malfunction causing false or misleading information to be
transmitted.
* * * * *
    (b) * * *
    (1) Aircraft operating in Class A airspace must have equipment
installed

that meets the antenna and power output requirements of Class A1S, A1,
A2, A3, B1S, or B1 equipment as defined in TSO-C166b and Section 2 of
RTCA DO-260B (as referenced in TSO-C166b), or TSO-C166c and Section 2
of RTCA DO-260C as modified by DO-260C--Change 1 (as referenced in TSO-
C166c).
    (2) * * *
    (i) Class A1S, A1, A2, A3, B1S, or B1 as defined in TSO-C166b and
Section 2 of RTCA DO-260B (as referenced in TSO-C166b) or TSO-C166c and
Section 2 of RTCA DO-260C as modified by DO-260C--Change 1 (as
referenced in TSO-C166c); or
    (ii) Class A1S, A1H, A2, A3, B1S, or B1 equipment as defined in
TSO-C154c and Section 2 of RTCA DO-282B (as referenced in TSO-C154c),
or TSO-C154d and Section 2 of RTCA DO-282C (as referenced in TSO-
C154d).
    (c) * * *
    (1) * * *
    (iv) The aircraft's SDA must be less than or equal to
10-5 per flight hour; and
    (v) The aircraft's SIL must be less than or equal to
10-7 per flight hour or per sample.
* * * * *
    (d) Minimum Broadcast Message Element Set for ADS-B Out. Each
aircraft must broadcast the following information, as defined in TSO-
C166b (including Section 2 of RTCA DO-260B, as referenced in TSO-
C166b), TSO-C166c (including Section 2 of RTCA DO-260C as modified by
DO-260C--Change 1, as referenced in TSO-C166c), TSO-C154c (including
Section 2 of RTCA DO-282B, as referenced in TSO-C154c), or TSO-C154d
(including Section 2 of RTCA DO-282C, as referenced in TSO-C154d). The
pilot must enter information for message elements listed in paragraphs
(d)(7) through (10) of this section during the appropriate phase of
flight.
* * * * *
    (5) An indication if a collision avoidance system is installed and
operating in a mode that can generate resolution advisory alerts;
    (6) If an operable collision avoidance system is installed, an
indication if a resolution advisory is in effect;
    (7) An indication of the Mode A transponder code specified by ATC;
    (8) An indication of the aircraft identification that is submitted
on the flight plan or used for communicating with ATC, except when the
pilot has not filed a flight plan, has not requested ATC services, and
is using a TSO-C154c or TSO-C154d self-assigned temporary 24-bit
address;
* * * * *
    (11) An indication of the aircraft assigned ICAO 24-bit address,
except when the pilot has not filed a flight plan, has not requested
ATC services, and is using a TSO-C154c or TSO-C154d self-assigned
temporary 24-bit address;
* * * * *
    (13) An indication of whether an ADS-B In capability is available;
* * * * *
    (g) Incorporation by reference. The standards required in this
section are incorporated by reference with the approval of the Director
of the Office of the Federal Register under 5 U.S.C. 552(a) and 1 CFR
part 51. This incorporation by reference (IBR) material is available
for inspection at the FAA and the National Archives and Records
Administration (NARA). Contact the FAA at: Office of Rulemaking (ARM-
1), 800 Independence Avenue SW, Washington, DC 20590 (telephone 202-
267-9677). For information on the availability of this material at
NARA, visit www.archives.gov/federal-register/cfr/ibr-locations.html or
email [email protected]. This material is also available from the
following sources indicated in this paragraph (g).
    (1) U.S. Department of Transportation, Subsequent Distribution
Office, DOT Warehouse M30, Ardmore East Business Center, 3341 Q 75th
Avenue, Landover, MD 20785; telephone<PHONE_NUMBER>; website:
www.faa.gov/aircraft/air_cert/design_approvals/tso/ (select the link
``Search Technical Standard Orders'').
    (i) TSO-C166b, Extended Squitter Automatic Dependent Surveillance-
Broadcast (ADS-B) and Traffic Information Service-Broadcast (TIS-B)
Equipment Operating on the Radio Frequency of 1090 Megahertz (MHz),
December 2, 2009.
    (ii) TSO-C166c, Extended Squitter Automatic Dependent Surveillance-
Broadcast (ADS-B) and Traffic Information Service-Broadcast (TIS-B)
Equipment Operating on the Radio Frequency of 1090 Megahertz (MHz),
March 10, 2023.
    (iii) TSO-C154c, Universal Access Transceiver (UAT) Automatic
Dependent Surveillance-Broadcast (ADS-B) Equipment Operating on the
Frequency of 978 MHz, December 2, 2009.
    (iv) TSO-C154d, Universal Access Transceiver (UAT) Automatic
Dependent Surveillance-Broadcast (ADS-B) Equipment Operating on the
Radio Frequency of 978 Megahertz (MHz), March 10, 2023.
    (2) RTCA, Inc., 1150 18th St. NW, Suite 910, Washington, DC 20036;
telephone<PHONE_NUMBER>; website: www.rtca.org/products.
    (i) RTCA DO-260B, Minimum Operational Performance Standards for
1090 MHz Extended Squitter Automatic Dependent Surveillance-Broadcast
(ADS-B) and Traffic Information Services-Broadcast (TIS-B), Section 2,
Equipment Performance Requirements and Test Procedures, December 2,
2009.
    (ii) RTCA DO-260C, Minimum Operational Performance Standards for
1090 MHz Extended Squitter Automatic Dependent Surveillance-Broadcast
(ADS-B) and Traffic Information Services-Broadcast (TIS-B), Section 2,
Equipment Performance Requirements and Test Procedures, December 17,
2020.
    (iii) RTCA DO-260C, Minimum Operational Performance Standards for
1090 MHz Extended Squitter Automatic Dependent Surveillance-Broadcast
(ADS-B) and Traffic Information Services-Broadcast (TIS-B), Change 1,
January 25, 2022.
    (iv) RTCA DO-282B, Minimum Operational Performance Standards for
Universal Access Transceiver (UAT) Automatic Dependent Surveillance-
Broadcast (ADS-B), Section 2, Equipment Performance Requirements and
Test Procedures, December 2, 2009.
    (v) RTCA DO-282C, Minimum Operational Performance Standards (MOPS)
for Universal Access Transceiver (UAT) Automatic Dependent
Surveillance-Broadcast (ADS-B), Section 2, Equipment Performance
Requirements and Test Procedures, June 23, 2022.

    Issued under authority provided by 49 U.S.C. 106(f), 40103, and
44701, in Washington, DC.
Polly E. Trottenberg,
Acting Administrator.
[FR Doc. 2023-22710 Filed 10-16-23; 8:45 am]
BILLING CODE 4910-13-P


	ENVIRONMENTAL PROTECTION AGENCY

	40 CFR Part 52

	[EPA-R03-OAR-2008-0183; FRL-        ]

Approval and Promulgation of Air Quality Implementation Plans;
Pennsylvania; Section 110(a)(1) 8-Hour Ozone Maintenance Plan and 2002
Base-Year Inventory for the Warren County Area

AGENCY:  Environmental Protection Agency (EPA).

ACTION:  Proposed rule

SUMMARY:  EPA is proposing to approve a State Implementation Plan (SIP)
revision submitted by the Commonwealth of Pennsylvania.  The
Pennsylvania Department of Environmental Protection (PADEP) submitted a
SIP revision consisting of a maintenance plan that provides for
continued attainment of the 8-hour ozone national ambient air quality
standard (NAAQS) for at least 10 years after the April 30, 2004
designations, as well as, a 2002 base-year inventory for the Warren
County Area.  EPA is proposing approval of the maintenance plan and the
2002 base-year inventory in accordance with the requirements of the
Clean Air Act (CAA).

DATES: Written comments must be received on or before [insert date 30
days from date of publication].

ADDRESSES:  Submit your comments, identified by Docket ID Number
EPA-R03-OAR-2008-0183 by one of the following methods:

 www.regulations.gov.  Follow the on-line instructions for submitting
comments.

     B.    E-mail<EMAIL_ADDRESS>
     C.    Mail:   EPA-R03-OAR-2008-0183, Cristina Fernandez, Chief, Air
Quality Planning Branch, Mailcode 3AP21, U.S. Environmental Protection
Agency, Region III, 1650 Arch Street, Philadelphia, Pennsylvania 19103.

     D.   Hand Delivery: At the previously-listed EPA Region III
address.  Such deliveries are only accepted during the Docket(s normal
hours of operation, and special arrangements should be made for
deliveries of boxed information.

Instructions:  Direct your comments to Docket ID No.
EPA-R03-OAR-2008-0183.  EPA's policy is that all comments received will
be included in the public docket without change, and may be made
available online at www.regulations.gov, including any personal
information provided, unless the comment includes information claimed to
be Confidential Business Information (CBI) or other information whose
disclosure is restricted by statute. Do not submit information that you
consider to be CBI or otherwise protected through www.regulations.gov or
e-mail.  The www.regulations.gov website is an (anonymous access(
system, which means EPA will not know your identity or contact
information unless you provide it in the body of your comment.  If you
send an e-mail comment directly to EPA without going through
www.regulations.gov, your e-mail address will be automatically captured
and included as part of the comment that is placed in the public docket
and made available on the Internet.  If you submit an electronic
comment, EPA recommends that you include your name and other contact
information in the body of your comment and with any disk or CD-ROM you
submit.  If EPA cannot read your comment due to technical difficulties
and cannot contact you for clarification, EPA may not be able to
consider your comment.  Electronic files should avoid the use of special
characters, any form of encryption, and be free of any defects or
viruses.

Docket:  All documents in the electronic docket are listed in the
www.regulations.gov index. Although listed in the index, some
information is not publicly available, i.e., CBI or other information
whose disclosure is restricted by statute.  Certain other material, such
as copyrighted material, is not placed on the Internet and will be
publicly available only in hard copy form.  Publicly available docket
materials are available either electronically in www.regulations.gov or
in hard copy during normal business hours at the Air Protection
Division, U.S. Environmental Protection Agency, Region III, 1650 Arch
Street, Philadelphia, Pennsylvania 19103. Copies of the State submittal
are available at Pennsylvania Department of Environmental Protection,
Bureau of Air Quality Control, P.O. Box 8468, 400 Market Street,
Harrisburg, Pennsylvania 17105.

FOR FURTHER INFORMATION CONTACT: Gregory Becoat,<PHONE_NUMBER>, or by
e-mail at<EMAIL_ADDRESS>
SUPPLEMENTARY INFORMATION:  On December 17, 2007, PADEP formally
submitted for approval, under section 110(a)(1) of the CAA, a SIP
revision for the 8-hour ozone maintenance plan and the 2002 base-year
inventory for the Warren County Area.

I.  Background

Section 110(a)(1) of the CAA requires that states submit to EPA plans to
maintain the NAAQS promulgated by EPA.  EPA interprets this provision to
require that areas that were maintenance areas for the 1-hour ozone
NAAQS, but attainment for the 8-hour ozone NAAQS, submit a plan to
demonstrate the continued maintenance of the 8-hour ozone NAAQS.

On May 20, 2005, EPA issued guidance that applies to areas that are
designated unclassifiable/attainment for the 8-hour ozone standard.  The
purpose of this guidance is to address the maintenance requirements in
section 110(a)(1) of the CAA, and to assist the states in the
development of a SIP.  The components from EPA’s guidance include:

(1) An attainment emissions inventory, which is based on actual
“typical summer day” emissions of volatile organic compounds (VOCs)
and nitrogen oxides (NOx) for a 10-year maintenance period, from a
base-year chosen by the state; (2) a maintenance demonstration, which
demonstrates how the area will remain in compliance with the 8-hour
ozone standard for a period of 10 years following the effective date of
designation unclassifiable/attainment (June 15, 2004); (3) an ambient
air monitoring network, which will be in continuous operation in
accordance with 40 CFR Part 58 to verify maintenance of the 8-hour ozone
standard; (4) a contingency plan, that will ensure that in the event of
a violation of the 8-hour ozone NAAQS, measures will be implemented as
promptly as possible; (5) a verification of continued attainment,
indicating how the state intends on tracking the progress of the
maintenance plan.

II.   Summary of SIP Revision

The Commonwealth of Pennsylvania has requested approval of its 8-hour
ozone maintenance plan and 2002 base-year inventory for the Warren
County Area.  The PADEP 8-hour ozone maintenance plan addresses the five
components of EPA’s May 20, 2005 guidance, which pertains to the
maintenance requirements in section 110(a)(1) of the CAA.

Attainment Emission Inventory:  An attainment emissions inventory
includes emissions during the time period associated with the monitoring
data showing attainment.  PADEP has provided an emissions inventory for
VOCs and NOx, using 2002 as the base-year from which to project
emissions.  The 2002 inventory is consistent with EPA guidance, is based
on actual “typical summer day” emissions of VOCs and NOx, and
consists of a list of sources and their associated emissions.  PADEP
prepared comprehensive VOCs and NOx emissions inventories for the Warren
County Area.  In the maintenance plan, PADEP included information on the
man-made sources of ozone precursors, VOCs and NOx (e.g., “stationary
sources,” “stationary area sources,” “highway vehicles,” and
“nonroad sources”).

Pennsylvania projected emissions for beyond 10 years from the effective
date of the April 30, 2004 designations for the 8-hour ozone standard.
PADEP has developed an emissions inventory for ozone precursors for the
year 2002, 2009, and 2018.  Tables 1 and 2 show the VOCs and NOx
emissions reduction summary for 2002, 2009, and 2018.

Table 1. - VOC Emissions Summary:  2002, 2009 and 2018

(tons per summer day)

Major Source Category	2002	2009	2018

Stationary Point Sources	1.56	0.92	1.10

Stationary Area Sources	2.71	2.47	2.55

Highway Vehicles	2.62	1.23	0.70

Nonroad Sources	2.62	2.02	1.29

TOTAL	9.51	6.64	5.64

Table 2. - NOx Emissions Summary:  2002, 2009 and 2018

(tons per summer day)

Major Source Category	2002	2009	2018

Stationary Point Sources	3.56	4.01	4.18

Stationary Area Sources	0.35	0.37	0.38

Highway Vehicles	4.04	1.95	0.76

Nonroad Sources	1.12	0.91	0.61

TOTAL	9.07	7.24	5.93

EPA believes Pennsylvania has demonstrated that the VOCs and NOx
emissions in the Warren County Area will improve due to permanent and
enforceable reductions in emissions resulting from implementation of the
SIP, federal measures, and other state-adopted measures.

Maintenance demonstration:  As Table 1 and 2 indicate, the Warren County
Attainment Area plan shows maintenance of the 8-hour ozone NAAQS by
demonstrating that future emissions of VOCs and NOx remain at or below
the 2002 base-year emissions levels through the year 2018.

Based upon the comparison of the projected emissions and the 2002
base-year inventory emissions, along federal and state measures, EPA
concludes that PADEP successfully demonstrates that the 8-hour ozone
standard will be maintained in the Warren County Area. Further details
of Warren County Attainment Area’s 8-hour ozone maintenance
demonstration can be found in a Technical Support Document (TSD)
prepared for this rulemaking.

Ambient Air Quality Monitoring:  With regard to the ambient air
monitoring component of the maintenance plan, Pennsylvania commits to
continue operating its current air quality monitoring stations in
accordance with 40 CFR Part 58, to verify the attainment status of the
area, with no reductions in the number of sites from those in the
existing network unless pre-approved by EPA.

Contingency Plan:  Section 110(a)(1) of the CAA requires that the state
develop a contingency plan which will ensure that any violation of a
NAAQS is promptly corrected.  The purpose of the contingency plan is to
adopt measures, outlined in the maintenance plan, in order to assure
continued attainment in the event of a violation of the 8-hour ozone
NAAQS.  The maintenance plan should identify the events that would
“trigger” the adoption and implementation of a contingency
measure(s), the contingency measure(s) that would be adopted and
implemented, and the schedule indicating the time frame by which the
state would adopt and implement the measure(s).

Since the Warren County Area does not have a monitor, contingency
measures will be considered if for two consecutive years the fourth
highest 8-hour ozone concentrations at the design monitor for the Erie
Area are above 84 parts per billion (ppb).  If this trigger point
occurs, PADEP will evaluate whether additional local emission control
measures should be implemented in Warren County in order to prevent a
violation of the air quality standard.  PADEP will analyze the
conditions leading to the excessive ozone levels and evaluate what
measures might be most effective in correcting the excessive ozone
levels.  PADEP will also analyze the potential emissions effect of
federal, state, and local measures that have been adopted but not yet
implemented at the time the excessive ozone levels occurred.  PADEP will
then begin the process of implementing the contingency measures outlined
in their maintenance plan.

Verification of continued attainment:  PADEP will track the attainment
status of the 8-hour ozone NAAQS for Warren County by reviewing air
quality at the design monitor for the Erie Area and emissions data
during the maintenance period.  An annual evaluation of vehicle miles
traveled and emissions reported from stationary sources will be
performed and compared to the assumptions about the factors used in the
maintenance plan. PADEP will also evaluate the periodic (every three
years) emission inventories prepared under EPA’s Consolidated Emission
Reporting Regulation (40 CFR 51, Subpart A) for any unanticipated
increases.  Based on these evaluations, PADEP will consider whether any
further emission control measures should be implemented.

III.   Proposed Action

EPA is proposing to approve the maintenance plan and the 2002 base-year
inventory for the Warren County Area, submitted on December 17, 2007, as
revisions to the Pennsylvania SIP.  EPA is proposing to approve the
maintenance plan and 2002 base-year inventory for the Warren County Area
because it meets the requirements of section 110(a)(1) of the CAA.  EPA
is soliciting public comments on the issues discussed in this document.
These comments will be considered before taking final action.

IV. Statutory and Executive Order Reviews

Under the CAA, the Administrator is required to approve a SIP submission
that complies with the provisions of the Act and applicable Federal
regulations.  42 U.S.C. 7410(k); 40 CFR 52.02(a).  Thus, in reviewing
SIP submissions, EPA’s role is to approve state choices, provided that
they meet the criteria of the CAA.  Accordingly, this action merely
proposes to approve state law as meeting Federal requirements and does
not impose additional requirements beyond those imposed by state law.
For that reason, this proposed action:

is not a "significant regulatory action” subject to review by the
Office of Management and Budget under Executive Order 12866 (58 FR
51735, October 4, 1993);

does not impose an information collection burden under the provisions of
the Paperwork Reduction Act (44 U.S.C. 3501 et seq.);

is certified as not having a significant economic impact on a
substantial number of small entities under the Regulatory Flexibility
Act (5 U.S.C. 601 et seq.);

does not contain any unfunded mandate or significantly or uniquely
affect small governments, as described in the Unfunded Mandates Reform
Act of 1995 (Public Law 104-4);

does not have Federalism implications as specified in Executive Order
13132 (64 FR 43255, August 10, 1999);

is not an economically significant regulatory action based on health or
safety risks subject to Executive Order 13045 (62 FR 19885, April 23,
1997);

is not a significant regulatory action subject to Executive Order 13211
(66 FR 28355, May 22, 2001);

is not subject to requirements of Section 12(d) of the National
Technology Transfer and Advancement Act of 1995 (15 U.S.C. 272 note)
because application of those requirements would be inconsistent with the
CAA; and

does not provide EPA with the discretionary authority to address, as
appropriate, disproportionate human health or environmental effects,
using practicable and legally permissible methods, under Executive Order
12898 (59 FR 7629, February 16, 1994).

In addition, this proposed rule to approve the maintenance plan and the
2002 base-year inventory for the Warren County Area in the Commonwealth
of Pennsylvania does not have tribal implications as specified by
Executive Order 13175 (65 FR 67249, November 9, 2000), because the SIP
is not approved to apply in Indian country located in the state, and EPA
notes that it will not impose substantial direct costs on tribal
governments or preempt tribal law.

List of Subjects in 40 CFR Part 52

Environmental protection, Air pollution control, Nitrogen dioxide,
Ozone, Reporting and recordkeeping requirements, Volatile organic
compounds.

Authority: 42 U.S.C. 7401 et seq.

__April 24, 2008_____________
________/s/____________________

Dated:
          William T. Wisniewski, Acting

               Regional Administrator,

               Region III.

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