AD 2024-19-06

final rule
Data completeness: 90%

Airworthiness Directives; The Boeing Company Airplanes

AD Number
2024-19-06
Status
final_rule
Effective Date
Product Category
aircraft
Docket
Docket No. FAA-2024-0229
FR Citation
89 FR 84264

Applicability

TypeManufacturerModelDetails
aircraft Boeing Company Airworthiness Directives; The Boeing Company Airplanes

Unsafe Condition

A single point of failure exists internal to the standby power system control unit (SPCU) design, which can result in a non-latent loss of the entire battery bus and consequent un-annunciated loss of control and indication of both engine anti-ice (EAI) systems.

AI-generated summary from the source AD text. Verify against the official source before acting.

Required Actions

Installing four diodes and changing wire bundles in the P5 panel, as well as performing installation and power tests and applicable on-condition actions.

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Compliance Time

Before further flight

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Affected Aircraft

The Boeing Company Model 737-8 and Model 737-9 airplanes.

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Document Text

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84264 Federal Register / Vol. 89, No. 204 / Tuesday, October 22, 2024 / Rules and Regulations correct operation of the safety belts, possibly resulting in injuries to seat occupants. (f) Compliance Comply with this AD within the compliance times specified, unless already done. (g) Requirements Except as specified in paragraph (h) of this AD: Comply with all required actions and compliance times specified in, and in accordance with, European Union Aviation Safety Agency (EASA) AD 2024–0051, dated February 23, 2024 (EASA AD 2024–0051). (h) Exceptions to EASA AD 2024–0051 (1) Where EASA AD 2024–0051 refers to its effective date, this AD requires using the effective date of this AD. (2) Where paragraph (2) of EASA AD 2024– 0051 specifies ‘‘if, during the inspection required by paragraph (1) of this AD, discrepancies are detected, as defined in the ASB, before next flight, contact Deutsche Aircraft GmbH and Collins Aerospace for approved instructions and accomplish those instructions accordingly,’’ this AD requires replacing that text with ‘‘if, during the inspection as required by paragraph (1) of this AD, any discrepancy is detected, the discrepancy must be repaired before further flight using a method approved by the Manager, International Validation Branch, FAA; or EASA; or Deutsche Aircraft GmbH’s EASA Design Organization Approval (DOA). If approved by the DOA, the approval must include the DOA-authorized signature.’’ (3) This AD does not adopt the ‘‘Remarks’’ section of EASA AD 2024–0051. (i) No Reporting or Return of Parts Requirement Although the service information referenced in EASA AD 2024–0051 specifies to submit certain information and send removed parts to the manufacturer, this AD does not include that requirement. (j) Additional AD Provisions The following provisions also apply to this AD: (1) Alternative Methods of Compliance (AMOCs): The Manager, International Validation Branch, FAA, has the authority to approve AMOCs for this AD, if requested using the procedures found in 14 CFR 39.19. In accordance with 14 CFR 39.19, send your request to your principal inspector or responsible Flight Standards Office, as appropriate. If sending information directly to the manager of the International Validation Branch, mail it to the address identified in paragraph (k) of this AD. Information may be emailed to: AMOC@faa.gov. Before using any approved AMOC, notify your appropriate principal inspector, or lacking a principal inspector, the manager of the responsible Flight Standards Office. (2) Contacting the Manufacturer: For any requirement in this AD to obtain instructions from a manufacturer, the instructions must be accomplished using a method approved by the Manager, International Validation Branch, FAA; or EASA; or Deutsche Aircraft GmbH’s EASA DOA. If approved by the DOA, the approval must include the DOA- authorized signature. (k) Additional Information For more information about this AD, contact Todd Thompson, Aviation Safety Engineer, FAA, 1600 Stewart Avenue, Suite 410, Westbury, NY 11590; telephone 206– 231–3228; email todd.thompson@faa.gov. (l) Material Incorporated by Reference (1) The Director of the Federal Register approved the incorporation by reference (IBR) of the material listed in this paragraph under 5 U.S.C. 552(a) and 1 CFR part 51. (2) You must use this material as applicable to do the actions required by this AD, unless this AD specifies otherwise. (i) European Union Aviation Safety Agency (EASA) AD 2024–0051, dated February 23, 2024. (ii) [Reserved] (3) For EASA AD 2024–0051, contact EASA, Konrad-Adenauer-Ufer 3, 50668 Cologne, Germany; telephone +49 221 8999 000; email ADs@easa.europa.eu; website easa.europa.eu. You may find this EASA AD on the EASA website ad.easa.europa.eu. (4) You may view this material at the FAA, Airworthiness Products Section, Operational Safety Branch, 2200 South 216th Street, Des Moines, WA. For information on the availability of this material at the FAA, call 206–231–3195. (5) You may view this material at the National Archives and Records Administration (NARA). For information on the availability of this material at NARA, visit www.archives.gov/federal-register/cfr/ ibr-locations or email fr.inspection@nara.gov. Issued on September 23, 2024. Victor Wicklund, Deputy Director, Compliance & Airworthiness Division, Aircraft Certification Service. [FR Doc. 2024–24386 Filed 10–21–24; 8:45 am] BILLING CODE 4910–13–P DEPARTMENT OF TRANSPORTATION Federal Aviation Administration 14 CFR Part 39 [Docket No. FAA–2024–0229; Project Identifier AD–2023–00485–T; Amendment 39–22848; AD 2024–19–06] RIN 2120–AA64 Airworthiness Directives; The Boeing Company Airplanes AGENCY : Federal Aviation Administration (FAA), DOT. ACTION : Final rule. SUMMARY : The FAA is adopting a new airworthiness directive (AD) for certain The Boeing Company Model 737–8 and Model 737–9 airplanes. This AD was prompted by a Boeing review of the standby power system control unit (SPCU) design where a single point of failure exists internal to the SPCU. This AD requires installing four diodes and changing wire bundles in the P5 panel, as well as performing installation and power tests and applicable on-condition actions. The FAA is issuing this AD to address the unsafe condition on these products. DATES : This AD is effective November 26, 2024 . The Director of the Federal Register approved the incorporation by reference of a certain publication listed in this AD as of November 26, 2024. ADDRESSES : AD Docket: You may examine the AD docket at regulations.gov under Docket No. FAA–2024–0229; or in person at Docket Operations between 9 a.m. and 5 p.m., Monday through Friday, except Federal holidays. The AD docket contains this final rule, any comments received, and other information. The address for Docket Operations is U.S. Department of Transportation, Docket Operations, M–30, West Building Ground Floor, Room W12–140, 1200 New Jersey Avenue SE, Washington, DC 20590. Material Incorporated by Reference: • For Boeing material identified in this AD, contact Boeing Commercial Airplanes, Attention: Contractual & Data Services (C&DS), 2600 Westminster Blvd., MC 110–SK57, Seal Beach, CA 90740–5600; telephone 562–797–1717; website myboeingfleet.com. • You may view this material at the FAA, Airworthiness Products Section, Operational Safety Branch, 2200 South 216th St., Des Moines, WA. For information on the availability of this material at the FAA, call 206–231–3195. It is also available at regulations.gov under Docket No. FAA–2024–0229. FOR FURTHER INFORMATION CONTACT : Raja Vengadasalam, Aviation Safety Engineer, FAA, 2200 South 216th St., Des Moines, WA 98198; telephone 206– 231–3537; email Raja.Vengadasalam@ faa.gov . SUPPLEMENTARY INFORMATION : Background The FAA issued a notice of proposed rulemaking (NPRM) to amend 14 CFR part 39 by adding an AD that would apply to certain The Boeing Company Model 737–8 and Model 737–9 airplanes. The NPRM published in the Federal Register on February 14, 2024 (89 FR 11231). The NPRM was prompted by a Boeing review of the SPCU design where a single point of failure exists internal to the SPCU. In the NPRM, the FAA proposed to require installing four diodes and changing wire bundles in the P5 panel, as well as VerDate Sep<11>2014 16:12 Oct 21, 2024 Jkt 265001 PO 00000 Frm 00010 Fmt 4700 Sfmt 4700 E:\FR\FM\22OCR1.SGM 22OCR1 ddrumheller on DSK120RN23PROD with RULES1

84265 Federal Register / Vol. 89, No. 204 / Tuesday, October 22, 2024 / Rules and Regulations performing installation and power tests and applicable on-condition actions. The FAA is issuing this AD to address a potential single point of failure in the SPCU, which can result in a non-latent loss of the entire battery bus and consequent un-annunciated loss of control and indication of both engine anti-ice (EAI) systems. Discussion of Final Airworthiness Directive Comments The FAA received comments from eight commenters who supported the NPRM without change. The FAA received additional comments from Alaska Airlines and two individuals. The following presents the comments received on the NPRM and the FAA’s response to each comment. Request for a ‘‘ Credit for Previous Actions ’’ Paragraph Alaska Airlines requested that the proposed AD be revised to include a ‘‘Credit for Previous Actions’’ paragraph that gives credit as specified in paragraph (h)(2), ‘‘Exceptions to Service Information Specifications,’’ of the proposed AD. Alaska requested credit for ‘‘ACTION 3’’ in the Action column of the table in the ‘‘Compliance’’ paragraph of Boeing Alert Requirements Bulletin 737–30A1083 RB, dated November 18, 2022, for airplanes on which the requirements bulletin was embodied prior to the effective date of this AD. The FAA disagrees with revising this AD to include a ‘‘Credit for Previous Actions’’ paragraph in this AD. Paragraph (f), ‘‘Compliance,’’ of this AD provides credit for required actions performed before the effective date of this AD. The FAA has not changed this AD as a result of this comment. Request for Clarification of AD Actions An individual was supportive, but requested clarification of whether the proposed AD adequately addresses the unsafe condition to prevent the single point of failure addressed by the proposed AD. The commenter also questioned what is being done so this condition does not occur again, and whether this is the only issue with this airplane design. The commenter also requested clarification of whether the affected airplanes would be grounded until the proposed AD actions are completed. The FAA worked with Boeing to develop appropriate actions, i.e., the diode installation and wire bundle change, using the procedures specified in Boeing Alert Requirements Bulletin 737–30A083 RB, dated November 18, 2022, to address the identified unsafe condition in this AD. This particular issue is the only one addressed by this AD. The FAA continuously evaluates operator and manufacturer reports and other data in order to promote safe type certification and production. Operators are required to comply with all applicable actions of an AD within the required compliance time and cannot later undo those required actions. The FAA’s safety analysis has determined that the compliance time for corrective action in this AD provides an acceptable level of safety. The FAA has not changed this AD as a result of this comment. Request for FAA’s Approach to Continued Operational Safety Another individual stated that the AD ‘‘prompted a review of’’ the SPCU and ‘‘found a design flaw.’’ The commenter acknowledged that the proposed AD would address the underlying problem, but questioned how long the condition has existed, whether the SPCU review addresses all systems on these airplanes, and whether affected airplanes remain in service until the concerns are addressed. This commenter stated that a deeper review into other models and ways to address these issues must be investigated. The FAA provides the following clarification. This AD did not prompt the SPCU review; rather, after the SPCU review conducted by Boeing, the FAA determined that an AD was necessary and appropriate to address the unsafe condition. The FAA continuously receives and evaluates performance and safety data from operators and manufacturers on all type-certificated airplanes. The FAA takes corrective action—whether advisory such as an advisory circular or mandatory such as an AD—as warranted by the facts. The FAA has not changed this AD as a result of this comment. Conclusion The FAA reviewed the relevant data, considered any comments received, and determined that air safety requires adopting this AD as proposed. Accordingly, the FAA is issuing this AD to address the unsafe condition on these products. Except for minor editorial changes, this AD is adopted as proposed in the NPRM. None of the changes will increase the economic burden on any operator. Material Incorporated by Reference Under 1 CFR Part 51 The FAA reviewed Boeing Alert Requirements Bulletin 737–30A083 RB, dated November 18, 2022. This material specifies procedures for installing four diodes and changing wire bundles in the P5 panel, as well as performing an anti-ice diode installation test and an engine anti-ice and wing anti-ice power test and applicable on-condition actions. On-condition actions include doing applicable corrective actions until the tests are passed. This material is reasonably available because the interested parties have access to it through their normal course of business or by the means identified in the ADDRESSES section. Costs of Compliance The FAA estimates that this AD affects 205 airplanes of U.S. registry. The FAA estimates the following costs to comply with this AD: E STIMATED C OSTS Action Labor cost Parts cost Cost per product Cost on U.S. operators Installation, Wiring bundle changes, and tests. Up to 18 work-hours × $85 per hour = Up to $1,530. Up to $3,760 ......... Up to $5,290 ......... Up to $1,084,450. The FAA has received no definitive data on which to base the cost estimates for the on-condition actions specified in this AD. The FAA has included all known costs in its cost estimate. According to the manufacturer, however, some or all of the costs of this AD may be covered under warranty, thereby reducing the cost impact on affected operators. Authority for This Rulemaking Title 49 of the United States Code specifies the FAA’s authority to issue rules on aviation safety. Subtitle I, section 106, describes the authority of VerDate Sep<11>2014 16:12 Oct 21, 2024 Jkt 265001 PO 00000 Frm 00011 Fmt 4700 Sfmt 4700 E:\FR\FM\22OCR1.SGM 22OCR1 ddrumheller on DSK120RN23PROD with RULES1

84266 Federal Register / Vol. 89, No. 204 / Tuesday, October 22, 2024 / Rules and Regulations the FAA Administrator. Subtitle VII: Aviation Programs, describes in more detail the scope of the Agency’s authority. The FAA is issuing this rulemaking under the authority described in Subtitle VII, Part A, Subpart III, Section 44701: General requirements. Under that section, Congress charges the FAA 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 regulation is within the scope of that authority because it addresses an unsafe condition that is likely to exist or develop on products identified in this rulemaking action. Regulatory Findings This AD will not have federalism implications under Executive Order 13132. This AD will not have a substantial direct effect on the States, on the relationship between the national government and the States, or on the distribution of power and responsibilities among the various levels of government. For the reasons discussed above, I certify that this AD: (1) Is not a ‘‘significant regulatory action’’ under Executive Order 12866, (2) Will not affect intrastate aviation in Alaska, and (3) Will not have a significant economic impact, positive or negative, on a substantial number of small entities under the criteria of the Regulatory Flexibility Act. List of Subjects in 14 CFR Part 39 Air transportation, Aircraft, Aviation safety, Incorporation by reference, Safety. The Amendment Accordingly, under the authority delegated to me by the Administrator, the FAA amends 14 CFR part 39 as follows: PART 39—AIRWORTHINESS DIRECTIVES ■ 1. The authority citation for part 39 continues to read as follows: Authority: 49 U.S.C. 106(g), 40113, 44701. § 39.13 [Amended] ■ 2. The FAA amends § 39.13 by adding the following new airworthiness directive: 2024–19–06 The Boeing Company: Amendment 39–22848; Docket No. FAA–2024–0229; Project Identifier AD– 2023–00485–T. (a) Effective Date This airworthiness directive (AD) is effective November 26, 2024. (b) Affected ADs None. (c) Applicability This AD applies to The Boeing Company Model 737–8 and 737–9 airplanes, certificated in any category, having a line number identified in paragraph 1.A., ‘‘Effectivity,’’ of Boeing Alert Requirements Bulletin 737–30A1083 RB, dated November 18, 2022. (d) Subject Air Transport Association (ATA) of America Code 30, Ice/Rain Protection System. (e) Unsafe Condition This AD was prompted by a Boeing review of the standby power system control unit (SPCU) design that determined a potential single point of failure exists in the SPCU. The FAA is issuing this AD to address a potential single point of failure in the SPCU, which can result in a non-latent loss of the entire battery bus and consequent un-annunciated loss of control and indication of both engine anti-ice (EAI) systems. The unsafe condition, if not addressed, could result in loss of thrust on both engines due to damage from operation in icing conditions without EAI and can result in loss of continued safe flight and landing. (f) Compliance Comply with this AD within the compliance times specified, unless already done. (g) Required Actions Except as specified by paragraph (h) of this AD: At the applicable times specified in the ‘‘Compliance’’ paragraph of Boeing Alert Requirements Bulletin 737–30A1083 RB, dated November 18, 2022, do all applicable actions identified in, and in accordance with, the Accomplishment Instructions of Boeing Alert Requirements Bulletin 737–30A1083 RB, dated November 18, 2022. Note 1 to paragraph (g): Guidance for accomplishing the actions required by this AD can be found in Boeing Alert Service Bulletin 737–30A1083, dated November 18, 2022, which is referred to in Boeing Alert Requirements Bulletin 737–30A1083 RB, dated November 18, 2022. (h) Exceptions to Service Information Specifications (1) Where the Compliance Time columns of the table in the ‘‘Compliance’’ paragraph of Boeing Alert Requirements Bulletin 737– 30A1083 RB, dated November 18, 2022, uses the phrase ‘‘the original issue date of Requirements Bulletin 737–30A1083 RB,’’ this AD requires using the effective date of this AD. (2) Where ‘‘ACTION 3’’ in the Action column of the table in the ‘‘Compliance’’ paragraph of Boeing Alert Requirements Bulletin 737–30A1083 RB, dated November 18, 2022, specifies to do applicable corrective actions and repeat the test until the test passes if any test fails, for this AD, the compliance time for those actions is before further flight after accomplishing the test. (i) Alternative Methods of Compliance (AMOCs) (1) The Manager, AIR–520, Continued Operational Safety Branch, FAA, has the authority to approve AMOCs for this AD, if requested using the procedures found in 14 CFR 39.19. In accordance with 14 CFR 39.19, send your request to your principal inspector or responsible Flight Standards Office, as appropriate. If sending information directly to the manager of AIR–520, Continued Operational Safety Branch, send it to the attention of the person identified in paragraph (j)(1) of this AD. Information may be emailed to: AMOC@faa.gov. (2) Before using any approved AMOC, notify your appropriate principal inspector, or lacking a principal inspector, the manager of the responsible Flight Standards Office. (3) An AMOC that provides an acceptable level of safety may be used for any repair, modification, or alteration required by this AD if it is approved by The Boeing Company Organization Designation Authorization (ODA) that has been authorized by the Manager, AIR–520, Continued Operational Safety Branch, FAA, to make those findings. To be approved, the repair method, modification deviation, or alteration deviation must meet the certification basis of the airplane, and the approval must specifically refer to this AD. (j) Related Information (1) For more information about this AD, contact Raja Vengadasalam, Aviation Safety Engineer, FAA, 2200 South 216th St., Des Moines, WA 98198; telephone 206–231– 3537; email Raja.Vengadasalam@faa.gov. (2) Material identified in this AD that is not incorporated by reference is available at the addresses specified in paragraph (k)(3) of this AD. (k) Material Incorporated by Reference (1) The Director of the Federal Register approved the incorporation by reference (IBR) of the material listed in this paragraph under 5 U.S.C. 552(a) and 1 CFR part 51. (2) You must use this material as applicable to do the actions required by this AD, unless the AD specifies otherwise. (i) Boeing Alert Requirements Bulletin 737–30A1083 RB, dated November 18, 2022. (ii) [Reserved] (3) For Boeing material identified in this AD, contact Boeing Commercial Airplanes, Attention: Contractual & Data Services (C&DS), 2600 Westminster Blvd., MC 110– SK57, Seal Beach, CA 90740–5600; telephone 562–797–1717; website myboeingfleet.com . (4) You may view this material at the FAA, Airworthiness Products Section, Operational Safety Branch, 2200 South 216th St., Des Moines, WA. For information on the availability of this material at the FAA, call 206–231–3195. (5) You may view this material at the National Archives and Records Administration (NARA). For information on the availability of this material at NARA, visit www.archives.gov/federal-register/cfr/ VerDate Sep<11>2014 16:12 Oct 21, 2024 Jkt 265001 PO 00000 Frm 00012 Fmt 4700 Sfmt 4700 E:\FR\FM\22OCR1.SGM 22OCR1 ddrumheller on DSK120RN23PROD with RULES1

84267 Federal Register / Vol. 89, No. 204 / Tuesday, October 22, 2024 / Rules and Regulations ibr-locations.html or email fr.inspection@ nara.gov. Issued on September 13, 2024. Peter A. White, Deputy Director, Integrated Certificate Management Division, Aircraft Certification Service. [FR Doc. 2024–24369 Filed 10–21–24; 8:45 am] BILLING CODE 4910–13–P DEPARTMENT OF TRANSPORTATION Federal Aviation Administration 14 CFR Part 39 [Docket No. FAA–2024–0759; Project Identifier AD–2023–01040–T; Amendment 39–22857; AD 2024–19–15] RIN 2120–AA64 Airworthiness Directives; Safran Aerosystems (Formerly AVOX Systems Inc.; Scott Aviation) Oxygen Cylinder and Valve Assemblies, and Oxygen Valve Assemblies AGENCY : Federal Aviation Administration (FAA), DOT. ACTION : Final rule. SUMMARY : The FAA is superseding Airworthiness Directive (AD) 2023–13– 11, which applied to certain AVOX Systems Inc. (formerly Scott Aviation) oxygen cylinder and valve assemblies, and oxygen valve assemblies, installed on but not limited to various transport airplanes. AD 2023–13–11 required inspecting the oxygen valve assemblies, and oxygen cylinder and valve assemblies, to determine the serial number of the valve, cylinder, and entire assembly; inspecting certain assemblies and parts for correct spacing of the gap between the bottom of the packing retainer and top of the valve body on the assemblies, and replacing assemblies having unacceptable gaps. AD 2023–13–11 also limited the installation of affected parts and required reporting inspection results and returning certain assemblies to the manufacturer. This AD was prompted by the determination that additional assemblies and parts are subject to the unsafe condition. This AD requires the actions specified in AD 2023–13–11 and expands the list of affected assemblies and parts. The FAA is issuing this AD to address the unsafe condition on these products. DATES : This AD is effective November 26, 2024. The Director of the Federal Register approved the incorporation by reference of certain publications listed in this AD as of November 26, 2024. The Director of the Federal Register approved the incorporation by reference of certain other publications listed in this AD as of September 5, 2023 (88 FR 50011, August 1, 2023). ADDRESSES : AD Docket: You may examine the AD docket at regulations.gov under Docket No. FAA–2024–0759; or in person at Docket Operations between 9 a.m. and 5 p.m., Monday through Friday, except Federal holidays. The AD docket contains this final rule, any comments received, and other information. The address for Docket Operations is U.S. Department of Transportation, Docket Operations, M–30, West Building Ground Floor, Room W12–140, 1200 New Jersey Avenue SE, Washington, DC 20590. Material Incorporated by Reference: • For AVOX and Safran Aerosystems material identified in this AD, contact AVOX Systems Inc., 225 Erie Street, Lancaster, NY 14086; telephone 716– 683–5100; website safranaerosystems.com. • You may view this material at the FAA, Airworthiness Products Section, Operational Safety Branch, 2200 South 216th St., Des Moines, WA. For information on the availability of this material at the FAA, call 206–231–3195. It is also available at regulations.gov under Docket No. FAA–2024–0759. FOR FURTHER INFORMATION CONTACT : Gabriel Kim, Aviation Safety Engineer, FAA, 1600 Stewart Avenue, Suite 410, Westbury, NY 11590; telephone 516– 228–7300; email 9-avs-nyaco-cos@ faa.gov. SUPPLEMENTARY INFORMATION : Background The FAA issued a notice of proposed rulemaking (NPRM) to amend 14 CFR part 39 to supersede AD 2023–13–11, Amendment 39–22496 (88 FR 50011, August 1, 2023) (AD 2023–13–11). AD 2023–13–11 applied to certain AVOX Systems Inc. (formerly Scott Aviation) oxygen cylinder and valve assemblies, and oxygen valve assemblies, installed on but not limited to various transport airplanes. AD 2023–13–11 was prompted by reports of cylinder and valve assemblies having oxygen leakage from the valve assembly vent hole, caused by the absence of a guide that maintains appropriate spacing between certain parts, and by a determination that additional assemblies and parts are affected by the unsafe condition addressed by AD 2022–04–09, Amendment 39–21951 (87 FR 10958, February 28, 2022) (AD 2022–04–09) (which was superseded by AD 2023–13– 11). The NPRM published in the Federal Register on March 25, 2024 (89 FR 20558). The NPRM was prompted by a report that the manufacturer identified additional assemblies and parts subject to the unsafe condition. In the NPRM, the FAA proposed to continue to require the actions specified in AD 2023–13–11 and require similar actions for those additional assemblies and parts. The FAA is issuing this AD to address oxygen leakage from the cylinder and valve assemblies, which could result in decreased or insufficient oxygen supply during a depressurization event; and heating or flow friction, which could cause an ignition event in the valve assembly. Discussion of Final Airworthiness Directive Comments The FAA received comments from four commenters, including Alaska Airlines (Alaska), American Airlines, Cathay Pacific Airways, Delta Air Lines (Delta), and SIAEC (SIA Engineering Company). The following presents the comments received on the NPRM and the FAA’s response to each comment. Request To Reference Later Revisions of Material Identified as Credit Alaska requested adding the required revisions of the material (identified in paragraphs (l)(1) through (3) of the proposed AD) to the group of material identified as acceptable material in paragraph (p)(3) of the proposed AD for actions accomplished before the effective date of this AD. The FAA disagrees with the request to revise paragraph (p)(3) of this AD. A global alternative method of compliance (AMOC) letter, 753–23–00200, was issued for AD 2023–13–11 that identified the required material in paragraphs (l)(1) through (3) of this AD as an acceptable AMOC. Accomplishment of the required material before the effective date of this AD to comply with the requirements of this AD is addressed by paragraph (f) of this AD. Paragraph (f) of this AD allows for the use of the required material before the effective date of this AD. No change to the AD has been made in this regard. Request for Clarification on Acceptable Material for Credit Conclusion SIAEC asked if credit can be granted for the actions specified in paragraphs (h) and (i) of the proposed AD if Revision 03 of the material was used. The FAA agrees to clarify. Paragraphs (h) and (i) of this AD still reference Revision 03 of the material as the primary means of compliance for those VerDate Sep<11>2014 16:12 Oct 21, 2024 Jkt 265001 PO 00000 Frm 00013 Fmt 4700 Sfmt 4700 E:\FR\FM\22OCR1.SGM 22OCR1 ddrumheller on DSK120RN23PROD with RULES1

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