Special Conditions: Airbus SAS Model A320 and A321 Series Airplanes; Rechargeable Lithium Batteries and Battery System Installations, 37467-37469 [2023-12278]

Download as PDF 37467 Rules and Regulations Federal Register Vol. 88, No. 110 Thursday, June 8, 2023 This section of the FEDERAL REGISTER contains regulatory documents having general applicability and legal effect, most of which are keyed to and codified in the Code of Federal Regulations, which is published under 50 titles pursuant to 44 U.S.C. 1510. The Code of Federal Regulations is sold by the Superintendent of Documents. DEPARTMENT OF TRANSPORTATION Federal Aviation Administration 14 CFR Part 25 [Docket No. FAA–2023–0841; Special Conditions No. 25–837–SC] Special Conditions: Airbus SAS Model A320 and A321 Series Airplanes; Rechargeable Lithium Batteries and Battery System Installations Federal Aviation Administration (FAA), DOT. ACTION: Final special conditions; request for comments. AGENCY: These special conditions are issued for the Airbus SAS (Airbus) Model A320–251N, –252N, –253N, –271N, –272N, and –273N; and Model A321–251NX, –252NX, –253NX, –271NX, and –272NX airplanes. These airplanes will have a novel or unusual design feature when compared to the state of technology envisioned in the airworthiness standards for transportcategory airplanes. This design feature is a mini emergency power supply unit containing rechargeable lithium-ion batteries. The applicable airworthiness regulations do not contain adequate or appropriate safety standards for this design feature. These special conditions contain the additional safety standards that the Administrator considers necessary to establish a level of safety equivalent to that established by the existing airworthiness standards. DATES: This action is effective on Airbus on June 8, 2023. Send comments on or before July 24, 2023. ADDRESSES: Send comments identified by Docket No. FAA–2023–0841 using any of the following methods: • Federal eRegulations 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 ddrumheller on DSK120RN23PROD with RULES1 SUMMARY: VerDate Sep<11>2014 15:15 Jun 07, 2023 Jkt 259001 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 202–493–2251. • Privacy: Except for Confidential Business Information as described in the following paragraph, and other information as described in title 14, Code of Federal Regulations (14 CFR) 11.35, the FAA will post all comments received without change to https:// www.regulations.gov/, including any personal information you provide. The FAA will also post a report summarizing each substantive verbal contact received about these special conditions. • 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 these special conditions contain commercial or financial information that is customarily treated as private, that you actually treat as private, and that is relevant or responsive to these special conditions, 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 the indicated comments will not be placed in the public docket of these special conditions. Send submissions containing CBI to the individual listed in the FOR FURTHER INFORMATION CONTACT section. Comments the FAA receives, which are not specifically designated as CBI, will be placed in the public docket for these special conditions. 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 Docket Operations in Room W12–140 of the West Building Ground Floor at 1200 PO 00000 Frm 00001 Fmt 4700 Sfmt 4700 New Jersey Avenue SE, Washington, DC, between 9 a.m. and 5 p.m., Monday through Friday, except Federal holidays. FOR FURTHER INFORMATION CONTACT: Nazih Khaouly, Aircraft Systems, AIR– 623, Technical Innovation Policy Branch, Policy and Innovation Division, Aircraft Certification Service, Federal Aviation Administration, 2200 South 216th Street, Des Moines, Washington 98198; telephone (206) 231–3160; email Nazih.khaouly@faa.gov. SUPPLEMENTARY INFORMATION: The substance of these special conditions has been published in the Federal Register for public comment in several prior instances with no substantive comments received. Therefore, the FAA finds, pursuant to 14 CFR 11.38(b), that new comments are unlikely, and notice and comment prior to this publication are unnecessary. Comments Invited The FAA invites interested people to take part in this rulemaking by sending written comments, data, or views. The most helpful comments reference a specific portion of the special conditions, explain the reason for any recommended change, and include supporting data. The FAA will consider all comments received by the closing date for comments, and will consider comments filed late if it is possible to do so without incurring delay. The FAA may change these special conditions based on the comments received. Background On August 17, 2022, Airbus SAS applied for a change to Type Certificate No. A28NM to install a mini emergency power supply unit containing rechargeable, lithium-ion batteries and battery system on Airbus A320–251N, –252N, –253N, –271N, –272N, and –273N and Airbus Model A321–251NX, –252NX, –253NX, –271NX, and –272NX airplanes. These airplanes, approved under Type Certificate No. A28NM, are twinengine transport category airplanes with a maximum seating of capacity between 179 to 244 passengers and a maximum takeoff weight between 154,322 to 213,848 pounds, depending on model. Type Certification Basis Under the provisions of title 14, Code of Federal Regulations (14 CFR) 21.101, E:\FR\FM\08JNR1.SGM 08JNR1 37468 Federal Register / Vol. 88, No. 110 / Thursday, June 8, 2023 / Rules and Regulations ddrumheller on DSK120RN23PROD with RULES1 Airbus must show that changes to the Airbus Model A320–251N, –252N, –253N, –271N, –272N, and –273N and Airbus Model A321–251NX, –252NX, –253NX, –271NX, and –272NX airplanes, as changed, continues to meet the applicable provisions of the regulations listed in Type Certificate No. A28NM or the applicable regulations in effect on the date of application for the change, except for earlier amendments as agreed upon by the FAA. If the Administrator finds that the applicable airworthiness regulations (e.g., 14 CFR part 25) do not contain adequate or appropriate safety standards for the Airbus Model A320–251N, –252N, –253N, –271N, –272N, and –273N, and Airbus Model A321–251NX, –252NX, –253NX, –271NX, and –272NX airplanes because of a novel or unusual design feature, special conditions are prescribed under the provisions of § 21.16. Special conditions are initially applicable to the model for which they are issued. Should the type certificate for that model be amended later to include any other model that incorporates the same novel or unusual design feature, or should any other model already included on the same type certificate be modified to incorporate the same novel or unusual design feature, these special conditions would also apply to the other model under § 21.101. In addition to the applicable airworthiness regulations and special conditions, the Airbus Model A320– 251N, –252N, –253N, –271N, –272N, and –273N, and Airbus Model A321– 251NX, –252NX, –253NX, –271NX, and –272NX airplanes must comply with the fuel-vent and exhaust-emission requirements of 14 CFR part 34, and the noise-certification requirements of 14 CFR part 36. The FAA issues special conditions, as defined in 14 CFR 11.19, in accordance with § 11.38, and they become part of the type certification basis under § 21.101. Novel or Unusual Design Features The Airbus Model A320–251N, –252N, –253N, –271N, –272N, and –273N; and Model A321–251NX, –252NX, –253NX, –271NX, and –272NX airplanes will incorporate the following novel or unusual design feature Mini Emergency Power Supply Unit containing rechargeable lithium-ion batteries. Discussion Rechargeable lithium batteries and battery systems are considered to be a novel or unusual design feature in VerDate Sep<11>2014 15:15 Jun 07, 2023 Jkt 259001 transport category airplanes, with respect to the requirements in § 25.1353. This type of battery has certain failure, operational, and maintenance characteristics that differ significantly from those of the nickel-cadmium and lead-acid rechargeable batteries currently approved for installation on transport category airplanes. These batteries and battery systems introduce higher energy levels into airplane systems through new chemical compositions in various battery-cell sizes and construction. Interconnection of these cells in battery packs introduces failure modes that require unique design considerations, such as provisions for thermal management. Special Condition 1 requires that each individual cell within a battery and battery system be designed to maintain safe temperatures and pressures. Special Condition 2 addresses these same issues but for the entire battery system. Special Condition 2 requires that the batteries and battery system be designed to prevent propagation of a thermal event, such as self-sustained, uncontrolled increases in temperature or pressure from one cell to adjacent cells. Special Conditions 1 and 2 are intended to ensure that the cells and battery system are designed to eliminate the potential for uncontrollable failures. However, a certain number of failures will occur due to various factors beyond the control of the designer. Therefore, other special conditions are intended to protect the airplane and its occupants if failure occurs. Special Conditions 3, 7, and 8 are selfexplanatory. Special Condition 4 clarifies that the flammable-fluid fire-protection requirements of § 25.863 apply to rechargeable lithium battery installations. Section 25.863 is applicable to areas of the airplane that could be exposed to flammable fluid leakage from airplane systems. Rechargeable lithium batteries contain electrolyte that is a flammable fluid. Special Condition 5 requires each rechargeable lithium battery and battery system installation to not damage surrounding structure or adjacent systems, equipment, or electrical wiring from corrosive fluids or gases that may escape in such a way as to cause a major or more severe failure condition. Special Condition 6 requires each rechargeable lithium battery and battery system installation to have provisions to prevent any hazardous effect on airplane structure or systems caused by the maximum amount of heat it can generate due to any failure of it or its individual cells. The means of meeting PO 00000 Frm 00002 Fmt 4700 Sfmt 4700 special conditions 5 and 6 may be the same, but they are independent requirements addressing different hazards. Special Condition 5 addresses corrosive fluids and gases, whereas special condition 6 addresses heat. Special Condition 9 requires rechargeable lithium batteries and battery systems to have ‘‘automatic’’ means, for charge rate and disconnect, due to the fast acting nature of lithium battery chemical reactions. Manual intervention would not be timely or effective in mitigating the hazards associated with these batteries. These special conditions apply to all rechargeable lithium batteries and battery system installations in lieu of § 25.1353(b)(1) through (4) at amendment 25–123, or § 25.1353(c)(1) through (4) at earlier amendments. Those regulations will remain in effect for other battery installations on these airplanes. These special conditions contain the additional safety standards that the Administrator considers necessary to establish a level of safety equivalent to that established by the existing airworthiness standards. Applicability As discussed above, these special conditions are applicable to the Airbus Model A320–251N, –252N, –253N, –271N, –272N, and –273N; and Model A321–251NX, –252NX, –253NX, –271NX, and –272NX airplanes. Should Airbus apply at a later date for a change to the type certificate to include another model incorporating the same novel or unusual design feature, these special conditions would apply to that model as well. Conclusion This action affects only certain novel or unusual design features on Airbus Model A320–251N, –252N, –253N, –271N, –272N, and –273N; and Model A321–251NX, –252NX, –253NX, –271NX, and –272NX airplanes. It is not a rule of general applicability. List of Subjects in 14 CFR Part 25 Aircraft, Aviation safety, Reporting and recordkeeping requirements. Authority Citation The authority citation for these special conditions is as follows: Authority: 49 U.S.C. 106(f), 106(g), 40113, 44701, 44702, and 44704. The Special Conditions Accordingly, pursuant to the authority delegated to me by the Administrator, the following special conditions are issued as part of the type E:\FR\FM\08JNR1.SGM 08JNR1 Federal Register / Vol. 88, No. 110 / Thursday, June 8, 2023 / Rules and Regulations certification basis for Airbus Model A320–251N, –252N, –253N, –271N, –272N and –273N; and Model A321– 251NX, –252NX, –253NX, –271NX and –272NX airplanes. Issued in Des Moines, Washington, on June 4, 2023. Suzanne A. Masterson, Acting Manager, Technical Policy Branch, Policy and Standards Division, Aircraft Certification Service. Rechargeable Lithium Battery and Battery System Installations [FR Doc. 2023–12278 Filed 6–7–23; 8:45 am] BILLING CODE 4910–13–P ddrumheller on DSK120RN23PROD with RULES1 In lieu of § 25.1353(b)(1) through (4) at amendment 25–123, or § 25.1353(c)(1) through (4) at earlier amendments, each rechargeable lithium battery installation must: 1. Be designed to maintain safe cell temperatures and pressures under all foreseeable operating conditions to prevent fire and explosion. 2. Be designed to prevent the occurrence of self-sustaining, uncontrollable increases in temperature or pressure, and automatically control the charge rate of each cell to protect against adverse operating conditions, such as cell imbalance, back charging, overcharging, and overheating. 3. Not emit explosive or toxic gases, either in normal operation or as a result of its failure that may accumulate in hazardous quantities within the airplane. 4. Meet the requirements of § 25.863. 5. Not damage surrounding structure or adjacent systems, equipment, or electrical wiring from corrosive fluids or gases that may escape in such a way as to cause a major or more- severe failure condition. 6. Have provisions to prevent any hazardous effect on airplane structure or systems caused by the maximum amount of heat it can generate due to any failure of it or its individual cells. 7. Have a failure sensing and warning system to alert the flightcrew if its failure affects safe operation of the airplane. 8. Have a monitoring and warning feature that alerts the flightcrew when its charge state falls below acceptable levels if its function is required for safe operation of the airplane. 9. Have a means to automatically disconnect from its charging source in the event of an over-temperature condition, cell failure or battery failure. Note: A battery system consists of the battery, battery charger and any protective, monitoring and alerting circuitry or hardware inside or outside of the battery. It also includes vents (where necessary) and packaging. For the purpose of these special conditions, a battery and the battery system is referred to as a battery. VerDate Sep<11>2014 15:15 Jun 07, 2023 Jkt 259001 DEPARTMENT OF TRANSPORTATION Federal Aviation Administration 14 CFR Part 71 [Docket No. FAA–2023–1254; Airspace Docket No. 23–ASO–23] RIN 2120–AA66 Amendment of Class E Airspace; West Palm Beach, FL Federal Aviation Administration (FAA), DOT. ACTION: Final rule. AGENCY: This action amends the West Palm Beach, FL Class E airspace legal description by removing ‘‘West Palm Beach’’ from the Palm Beach International Airport name in the West Palm Beach Class E airspace legal description sub-header as it is excessive and unnecessary. This action does not change the boundaries, altitudes, or operating requirements of the Class E airspace area. DATES: Effective 0901 UTC, August 10, 2023. The Director of the Federal Register approves this incorporation by reference action under 1 CFR part 51, subject to the annual revision of FAA Order JO 7400.11 and publication of conforming amendments. ADDRESSES: This final rule and all background material may be viewed online at www.regulations.gov using the FAA Docket number. Electronic retrieval help and guidelines are available on the website. It is available 24 hours a day, 365 days a year. FAA Order JO 7400.11G, Airspace Designations and Reporting Points, and subsequent amendments can be viewed online at www.faa.gov/air_traffic/ publications/. You may also contact the Rules and Regulations Group, Office of Policy, Federal Aviation Administration, 800 Independence Avenue SW, Washington, DC 20591; telephone: (202) 267–8783. FOR FURTHER INFORMATION, CONTACT: Jennifer Ledford, Operations Support Group, Eastern Service Center, Federal Aviation Administration, 1701 Columbia Avenue, College Park, GA 30337; Telephone: (404) 305–5649. SUPPLEMENTARY INFORMATION: SUMMARY: PO 00000 Frm 00003 Fmt 4700 Sfmt 4700 37469 Authority for This Rulemaking The FAA’s authority to issue rules regarding aviation safety is found in Title 49 of the United States Code. 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. Under that section, the FAA is charged with prescribing regulations to assign the use of airspace necessary to ensure the safety of aircraft and the efficient use of airspace. This regulation is within the scope of that authority, as it amends the Class E5 airspace description in West Palm Beach, FL, by removing ‘‘West Palm Beach’’ from the legal description sub-header because it is excessive and unnecessary. Incorporation by Reference Class E airspace designations are published in Paragraph 6005 of FAA Order JO 7400.11, Airspace Designations and Reporting Points, incorporated by reference in 14 CFR 71.1 annually. This document amends the current version of that order, FAA Order JO 7400.11G, Airspace Designations and Reporting Points, dated August 19, 2022, and effective September 15, 2022. These updates would subsequently be published in the next update to FAA Order JO 7400.11. FAA Order JO 7400.11G is publicly available as listed in the ADDRESSES section of this document. FAA Order JO 7400.11G lists Class A, B, C, D, and E airspace areas, air traffic service routes, and reporting points. The Rule This action amends 14 CFR part 71 by amending Class E airspace extending upward from 700 Feet or more above the surface of the earth for Palm Beach International Airport, West Palm Beach, FL, by removing ‘‘West Palm Beach’’ from the legal description sub-header because it is excessive and unnecessary. This action does not affect the boundaries, altitudes, or operating requirements of the airspace. Therefore, notice and public procedure under 5 U.S.C. 553(b) is unnecessary. Regulatory Notices and Analyses The FAA has determined that this regulation only involves an established body of technical regulations for which frequent and routine amendments are necessary to keep them operationally current. It, therefore: (1) is not a ‘‘significant regulatory action’’ under Executive Order 12866; (2) is not a E:\FR\FM\08JNR1.SGM 08JNR1

Agencies

[Federal Register Volume 88, Number 110 (Thursday, June 8, 2023)]
[Rules and Regulations]
[Pages 37467-37469]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2023-12278]



========================================================================
Rules and Regulations
                                                Federal Register
________________________________________________________________________

This section of the FEDERAL REGISTER contains regulatory documents 
having general applicability and legal effect, most of which are keyed 
to and codified in the Code of Federal Regulations, which is published 
under 50 titles pursuant to 44 U.S.C. 1510.

The Code of Federal Regulations is sold by the Superintendent of Documents. 

========================================================================


Federal Register / Vol. 88 , No. 110 / Thursday, June 8, 2023 / Rules 
and Regulations

[[Page 37467]]



DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 25

[Docket No. FAA-2023-0841; Special Conditions No. 25-837-SC]


Special Conditions: Airbus SAS Model A320 and A321 Series 
Airplanes; Rechargeable Lithium Batteries and Battery System 
Installations

AGENCY: Federal Aviation Administration (FAA), DOT.

ACTION: Final special conditions; request for comments.

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

SUMMARY: These special conditions are issued for the Airbus SAS 
(Airbus) Model A320-251N, -252N, -253N, -271N, -272N, and -273N; and 
Model A321-251NX, -252NX, -253NX, -271NX, and -272NX airplanes. These 
airplanes will have a novel or unusual design feature when compared to 
the state of technology envisioned in the airworthiness standards for 
transport-category airplanes. This design feature is a mini emergency 
power supply unit containing rechargeable lithium-ion batteries. The 
applicable airworthiness regulations do not contain adequate or 
appropriate safety standards for this design feature. These special 
conditions contain the additional safety standards that the 
Administrator considers necessary to establish a level of safety 
equivalent to that established by the existing airworthiness standards.

DATES: This action is effective on Airbus on June 8, 2023. Send 
comments on or before July 24, 2023.

ADDRESSES: Send comments identified by Docket No. FAA-2023-0841 using 
any of the following methods:
     Federal eRegulations 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 202-493-2251.
     Privacy: Except for Confidential Business Information as 
described in the following paragraph, and other information as 
described in title 14, Code of Federal Regulations (14 CFR) 11.35, the 
FAA will post all comments received without change to https://www.regulations.gov/, including any personal information you provide. 
The FAA will also post a report summarizing each substantive verbal 
contact received about these special conditions.
     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 these special 
conditions contain commercial or financial information that is 
customarily treated as private, that you actually treat as private, and 
that is relevant or responsive to these special conditions, 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 the indicated comments will not be placed in the public 
docket of these special conditions. Send submissions containing CBI to 
the individual listed in the FOR FURTHER INFORMATION CONTACT section. 
Comments the FAA receives, which are not specifically designated as 
CBI, will be placed in the public docket for these special conditions.
    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 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: Nazih Khaouly, Aircraft Systems, AIR-
623, Technical Innovation Policy Branch, Policy and Innovation 
Division, Aircraft Certification Service, Federal Aviation 
Administration, 2200 South 216th Street, Des Moines, Washington 98198; 
telephone (206) 231-3160; email [email protected].

SUPPLEMENTARY INFORMATION: The substance of these special conditions 
has been published in the Federal Register for public comment in 
several prior instances with no substantive comments received. 
Therefore, the FAA finds, pursuant to 14 CFR 11.38(b), that new 
comments are unlikely, and notice and comment prior to this publication 
are unnecessary.

Comments Invited

    The FAA invites interested people to take part in this rulemaking 
by sending written comments, data, or views. The most helpful comments 
reference a specific portion of the special conditions, explain the 
reason for any recommended change, and include supporting data.
    The FAA will consider all comments received by the closing date for 
comments, and will consider comments filed late if it is possible to do 
so without incurring delay. The FAA may change these special conditions 
based on the comments received.

Background

    On August 17, 2022, Airbus SAS applied for a change to Type 
Certificate No. A28NM to install a mini emergency power supply unit 
containing rechargeable, lithium-ion batteries and battery system on 
Airbus A320-251N, -252N, -253N, -271N, -272N, and -273N and Airbus 
Model A321-251NX, -252NX, -253NX, -271NX, and -272NX airplanes.
    These airplanes, approved under Type Certificate No. A28NM, are 
twin-engine transport category airplanes with a maximum seating of 
capacity between 179 to 244 passengers and a maximum takeoff weight 
between 154,322 to 213,848 pounds, depending on model.

Type Certification Basis

    Under the provisions of title 14, Code of Federal Regulations (14 
CFR) 21.101,

[[Page 37468]]

Airbus must show that changes to the Airbus Model A320-251N, -252N, -
253N, -271N, -272N, and -273N and Airbus Model A321-251NX, -252NX, -
253NX, -271NX, and -272NX airplanes, as changed, continues to meet the 
applicable provisions of the regulations listed in Type Certificate No. 
A28NM or the applicable regulations in effect on the date of 
application for the change, except for earlier amendments as agreed 
upon by the FAA.
    If the Administrator finds that the applicable airworthiness 
regulations (e.g., 14 CFR part 25) do not contain adequate or 
appropriate safety standards for the Airbus Model A320-251N, -252N, -
253N, -271N, -272N, and -273N, and Airbus Model A321-251NX, -252NX, -
253NX, -271NX, and -272NX airplanes because of a novel or unusual 
design feature, special conditions are prescribed under the provisions 
of Sec.  21.16.
    Special conditions are initially applicable to the model for which 
they are issued. Should the type certificate for that model be amended 
later to include any other model that incorporates the same novel or 
unusual design feature, or should any other model already included on 
the same type certificate be modified to incorporate the same novel or 
unusual design feature, these special conditions would also apply to 
the other model under Sec.  21.101.
    In addition to the applicable airworthiness regulations and special 
conditions, the Airbus Model A320-251N, -252N, -253N, -271N, -272N, and 
-273N, and Airbus Model A321-251NX, -252NX, -253NX, -271NX, and -272NX 
airplanes must comply with the fuel-vent and exhaust-emission 
requirements of 14 CFR part 34, and the noise-certification 
requirements of 14 CFR part 36.
    The FAA issues special conditions, as defined in 14 CFR 11.19, in 
accordance with Sec.  11.38, and they become part of the type 
certification basis under Sec.  21.101.

Novel or Unusual Design Features

    The Airbus Model A320-251N, -252N, -253N, -271N, -272N, and -273N; 
and Model A321-251NX, -252NX, -253NX, -271NX, and -272NX airplanes will 
incorporate the following novel or unusual design feature Mini 
Emergency Power Supply Unit containing rechargeable lithium-ion 
batteries.

Discussion

    Rechargeable lithium batteries and battery systems are considered 
to be a novel or unusual design feature in transport category 
airplanes, with respect to the requirements in Sec.  25.1353. This type 
of battery has certain failure, operational, and maintenance 
characteristics that differ significantly from those of the nickel-
cadmium and lead-acid rechargeable batteries currently approved for 
installation on transport category airplanes. These batteries and 
battery systems introduce higher energy levels into airplane systems 
through new chemical compositions in various battery-cell sizes and 
construction. Interconnection of these cells in battery packs 
introduces failure modes that require unique design considerations, 
such as provisions for thermal management.
    Special Condition 1 requires that each individual cell within a 
battery and battery system be designed to maintain safe temperatures 
and pressures. Special Condition 2 addresses these same issues but for 
the entire battery system.
    Special Condition 2 requires that the batteries and battery system 
be designed to prevent propagation of a thermal event, such as self-
sustained, uncontrolled increases in temperature or pressure from one 
cell to adjacent cells.
    Special Conditions 1 and 2 are intended to ensure that the cells 
and battery system are designed to eliminate the potential for 
uncontrollable failures. However, a certain number of failures will 
occur due to various factors beyond the control of the designer. 
Therefore, other special conditions are intended to protect the 
airplane and its occupants if failure occurs.
    Special Conditions 3, 7, and 8 are self-explanatory.
    Special Condition 4 clarifies that the flammable-fluid fire-
protection requirements of Sec.  25.863 apply to rechargeable lithium 
battery installations. Section 25.863 is applicable to areas of the 
airplane that could be exposed to flammable fluid leakage from airplane 
systems. Rechargeable lithium batteries contain electrolyte that is a 
flammable fluid.
    Special Condition 5 requires each rechargeable lithium battery and 
battery system installation to not damage surrounding structure or 
adjacent systems, equipment, or electrical wiring from corrosive fluids 
or gases that may escape in such a way as to cause a major or more 
severe failure condition.
    Special Condition 6 requires each rechargeable lithium battery and 
battery system installation to have provisions to prevent any hazardous 
effect on airplane structure or systems caused by the maximum amount of 
heat it can generate due to any failure of it or its individual cells. 
The means of meeting special conditions 5 and 6 may be the same, but 
they are independent requirements addressing different hazards. Special 
Condition 5 addresses corrosive fluids and gases, whereas special 
condition 6 addresses heat.
    Special Condition 9 requires rechargeable lithium batteries and 
battery systems to have ``automatic'' means, for charge rate and 
disconnect, due to the fast acting nature of lithium battery chemical 
reactions. Manual intervention would not be timely or effective in 
mitigating the hazards associated with these batteries.
    These special conditions apply to all rechargeable lithium 
batteries and battery system installations in lieu of Sec.  
25.1353(b)(1) through (4) at amendment 25-123, or Sec.  25.1353(c)(1) 
through (4) at earlier amendments. Those regulations will remain in 
effect for other battery installations on these airplanes.
    These special conditions contain the additional safety standards 
that the Administrator considers necessary to establish a level of 
safety equivalent to that established by the existing airworthiness 
standards.

Applicability

    As discussed above, these special conditions are applicable to the 
Airbus Model A320-251N, -252N, -253N, -271N, -272N, and -273N; and 
Model A321-251NX, -252NX, -253NX, -271NX, and -272NX airplanes. Should 
Airbus apply at a later date for a change to the type certificate to 
include another model incorporating the same novel or unusual design 
feature, these special conditions would apply to that model as well.

Conclusion

    This action affects only certain novel or unusual design features 
on Airbus Model A320-251N, -252N, -253N, -271N, -272N, and -273N; and 
Model A321-251NX, -252NX, -253NX, -271NX, and -272NX airplanes. It is 
not a rule of general applicability.

List of Subjects in 14 CFR Part 25

    Aircraft, Aviation safety, Reporting and recordkeeping 
requirements.

Authority Citation

    The authority citation for these special conditions is as follows:

    Authority: 49 U.S.C. 106(f), 106(g), 40113, 44701, 44702, and 
44704.

The Special Conditions

    Accordingly, pursuant to the authority delegated to me by the 
Administrator, the following special conditions are issued as part of 
the type

[[Page 37469]]

certification basis for Airbus Model A320-251N, -252N, -253N, -271N, -
272N and -273N; and Model A321-251NX, -252NX, -253NX, -271NX and -272NX 
airplanes.

Rechargeable Lithium Battery and Battery System Installations

    In lieu of Sec.  25.1353(b)(1) through (4) at amendment 25-123, or 
Sec.  25.1353(c)(1) through (4) at earlier amendments, each 
rechargeable lithium battery installation must:
    1. Be designed to maintain safe cell temperatures and pressures 
under all foreseeable operating conditions to prevent fire and 
explosion.
    2. Be designed to prevent the occurrence of self-sustaining, 
uncontrollable increases in temperature or pressure, and automatically 
control the charge rate of each cell to protect against adverse 
operating conditions, such as cell imbalance, back charging, 
overcharging, and overheating.
    3. Not emit explosive or toxic gases, either in normal operation or 
as a result of its failure that may accumulate in hazardous quantities 
within the airplane.
    4. Meet the requirements of Sec.  25.863.
    5. Not damage surrounding structure or adjacent systems, equipment, 
or electrical wiring from corrosive fluids or gases that may escape in 
such a way as to cause a major or more- severe failure condition.
    6. Have provisions to prevent any hazardous effect on airplane 
structure or systems caused by the maximum amount of heat it can 
generate due to any failure of it or its individual cells.
    7. Have a failure sensing and warning system to alert the 
flightcrew if its failure affects safe operation of the airplane.
    8. Have a monitoring and warning feature that alerts the flightcrew 
when its charge state falls below acceptable levels if its function is 
required for safe operation of the airplane.
    9. Have a means to automatically disconnect from its charging 
source in the event of an over-temperature condition, cell failure or 
battery failure.

    Note:  A battery system consists of the battery, battery charger 
and any protective, monitoring and alerting circuitry or hardware 
inside or outside of the battery. It also includes vents (where 
necessary) and packaging. For the purpose of these special 
conditions, a battery and the battery system is referred to as a 
battery.


    Issued in Des Moines, Washington, on June 4, 2023.
Suzanne A. Masterson,
Acting Manager, Technical Policy Branch, Policy and Standards Division, 
Aircraft Certification Service.
[FR Doc. 2023-12278 Filed 6-7-23; 8:45 am]
BILLING CODE 4910-13-P

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