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 Department of Transportation Federal Aviation Administration 14 CFR Part 39
[Docket No. FAA-2023-2003; Project Identifier AD-2022-01620-T]
RIN 2120-AA64
 AGENCY: Federal Aviation Administration (FAA), DOT.
 ACTION: Notice of proposed rulemaking (NPRM).
 SUMMARY: The FAA proposes to adopt a new airworthiness directive (AD) for certain The Boeing Company Model 757 airplanes. This proposed AD was prompted by reports of operators finding frequent and severe damage to the blowout vent grills of the aft soft bulkhead lining in the aft lower lobe cargo compartment. This proposed AD would require repetitive detailed inspections of certain decompression panels and pressure equalization valves, as applicable, in the forward and aft lower lobe cargo compartments for damage, and applicable on-condition actions. For certain airplanes, this proposed AD would also require replacement of a certain soft bulkhead with a rigid bulkhead. For certain other airplanes, this proposed AD would require installation of doublers to a certain bulkhead assembly panel. The FAA is proposing this AD to address the unsafe condition on these products.
 DATES: The FAA must receive comments on this proposed AD by December 11, 2023.
 ADDRESSES: You may send comments, using the procedures found in 14 CFR 11.43 and 11.45, by any of the following methods: *Federal eRulemaking Portal:*
                         Go to 
                        *regulations.gov*. Follow the instructions for submitting comments.
                    *Fax:*
                         202-493-2251.
                    *Mail:*
                         U.S. Department of Transportation, Docket Operations, M-30, West Building Ground Floor, Room W12-140, 1200 New Jersey Avenue SE, Washington, DC 20590.
                    *Hand Delivery:*
                         Deliver to Mail address above between 9 a.m. and 5 p.m., Monday through Friday, except Federal holidays. *AD Docket:*
                         You may examine the AD docket at 
                        *regulations.gov*
                         under Docket No. FAA-2023-2003; 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 NPRM, any comments received, and other information. The street address for Docket Operations is listed above. *Material Incorporated by Reference:* For service information identified in this NPRM, 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 service information 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*
                         by searching for and locating Docket No. FAA-2023-2003.
 FOR FURTHER INFORMATION CONTACT: Katherine Venegas, Aviation Safety Engineer, FAA, 2200 South 216th St., Des Moines, WA 98198; telephone: 562-627-5353; email: 
                        *Katherine.Venegas@faa.gov.*


SUPPLEMENTARY INFORMATION: Comments Invited The FAA invites you to send any written relevant data, views, or arguments about this proposal. Send your comments to an address listed under 
                    **ADDRESSES**
                    . Include “Docket No. FAA-2023-2003; Project Identifier AD-2022-01620-T” at the beginning of your comments. The most helpful comments reference a specific portion of the proposal, explain the reason for any recommended change, and include supporting data. The FAA will consider all comments received by the closing date and may amend this proposal because of those comments. Except for Confidential Business Information (CBI) as described in the following paragraph, and other information as described in 14 CFR 11.35, the FAA will post all comments received, without change, to 
                    *regulations.gov*, including any personal information you provide. The agency will also post a report summarizing each substantive verbal contact received about this NPRM. Confidential Business Information CBI is commercial or financial information that is both customarily and actually treated as private by its owner. Under the Freedom of Information Act (FOIA) (5 U.S.C. 552), CBI is exempt from public disclosure. If your comments responsive to this NPRM contain commercial or financial information that is customarily treated as private, that you actually treat as private, and that is relevant or responsive to this NPRM, it is important that you clearly designate the submitted comments as CBI. Please mark each page of your submission containing CBI as “PROPIN.” The FAA will treat such marked submissions as confidential under the FOIA, and they will not be placed in the public docket of this NPRM. Submissions containing CBI should be sent to Katherine Venegas, Aviation Safety Engineer, FAA, 2200 South 216th St., Des Moines, WA 98198; telephone: 562-627-5353; email: 
                    *Katherine.Venegas@faa.gov.*
                     Any commentary that the FAA receives that is not specifically designated as CBI will be placed in the public docket for this rulemaking. Background Operators have found, on multiple aircraft, frequent and severe damage to the blowout vent grills of the aft soft bulkhead lining in the lower lobe cargo compartment. Damage to the grill assembly consisted of bent, fractured, and missing sections of tubing; deformed frames; and twisted cross members. Boeing investigated the reported damage and found the blowout vent grills are vulnerable to being damaged during baggage loading and unloading. Damage to the blowout vent grills in the forward and aft lower lobe cargo compartments could lead to latent failure of the decompression panels and pressure equalization valves. This latent failure, in combination with a fire, could make the cargo fire protection, detection, suppression, and containment system ineffective. Also, 
                    ( print page 73544)
                    this latent failure, in combination with rapid decompression of the airplane, could prevent activation of the station (STA) 1640 decompression panels, which could damage the STA 1640 floor beam and cause loss of hydraulic systems components and flight control. This condition, if not addressed could result in the inability of the flightcrew to maintain safe flight and landing. FAA's Determination The FAA is issuing this NPRM after determining that the unsafe condition described previously is likely to exist or develop on other products of the same type design. Related Service Information Under 1 CFR Part 51 The FAA reviewed Boeing Alert Requirements Bulletin 757-25A0319 RB, dated March 24, 2023. This service information specifies procedures for repetitive detailed inspections of certain bulkhead (including STA 1640), sidewall, ceiling, and E5 EE rack decompression panels, and pressure equalization valves on certain airplanes, in the forward and aft lower lobe cargo compartments for damage; and applicable on-condition actions. On-condition actions include repair or replacement of any damaged decompression panels or pressure equalization valves. For certain airplanes, this service information also specifies procedures for replacing the soft bulkhead at STA 1640 with a rigid bulkhead having decompression panels with billet grilles. For certain other airplanes, this service information specifies procedures for installing doublers to the bulkhead assembly panel at STA 1640. This service information is reasonably available because the interested parties have access to it through their normal course of business or by the means identified in 
                    **ADDRESSES**
                    . Proposed AD Requirements in This NPRM This proposed AD would require accomplishing the actions specified in the service information already described, except for any differences identified as exceptions in the regulatory text of this proposed AD. For information on the procedures and compliance times, see this service information at 
                    *regulations.gov*
                     under Docket No. FAA-2023-2003. Costs of Compliance The FAA estimates that this AD, if adopted as proposed, would affect 489 airplanes of U.S. registry. The FAA estimates the following costs to comply with this proposed AD: Estimated Costs
Action
Labor cost
Parts
                             cost
Cost per
                             product
Cost on U.S.
                             operatorsDetailed Inspection
Up to 21 work-hours × $85 per hour = $1,785 per inspection cycle
$0
Up to $1,785 per inspection cycle
Up to $872,865 per inspection cycle.Replacement of soft bulkhead (100 airplanes)
10 work-hours × $85 per hour = $850
108,240
109,090
10,909,000.Installation of doublers (7 airplanes)
2 work-hours × $85 per hour = $170
1,760
$1,930
13,510.
 The FAA estimates the following costs to do any necessary repair or replacement that would be required based on the results of the proposed inspection. The agency has no way of determining the number of aircraft that might need this repair or replacement: On-Condition Costs
Action
Labor cost
Parts cost
Cost per
                             productRepair
12 work-hours × $85 per hour = $1,020
$54,120
$55,140Replacement
12 work-hour × $85 per hour = $1,020
108,240
109,260
 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 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 The FAA determined that this proposed AD would not have federalism implications under Executive Order 13132. This proposed AD would 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 this proposed regulation: (1) Is not a “significant regulatory action” under Executive Order 12866, (2) Would not affect intrastate aviation in Alaska, and (3) Would 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 Proposed Amendment Accordingly, under the authority delegated to me by the Administrator, the FAA proposes to amend 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
 2.The FAA amends § 39.13 by adding the following new airworthiness directive: **The Boeing Company:**
                         Docket No. FAA-2023-2003; Project Identifier AD-2022-01620-T. (a) Comments Due Date The FAA must receive comments on this airworthiness directive (AD) by December 11, 2023. (b) Affected ADs None. (c) Applicability This AD applies to The Boeing Company Model 757-200, -200PF, -200CB, and -300 series airplanes, certificated in any category, as identified in Boeing Alert Requirements Bulletin 757-25A0319 RB, dated March 24, 2023. (d) Subject Air Transport Association (ATA) of America Code 25, Equipment/Furnishings. (e) Unsafe Condition This AD was prompted by reports that operators have found, on multiple aircraft, frequent and severe damage to the blowout vent grills of the aft soft bulkhead lining in the lower lobe cargo compartment. The FAA is issuing this AD to address damage to the blowout vent grills in the forward and aft lower lobe cargo compartments that could lead to latent failure of the decompression panels and pressure equalization valves. This latent failure, in combination with a fire, could make the cargo fire protection, detection, suppression, and containment system ineffective. Also, this latent failure, in combination with rapid decompression of the airplane, could prevent activation of the station (STA) 1640 decompression panels, which could damage the STA 1640 floor beam and cause loss of hydraulic systems components and flight control. This unsafe condition, if not addressed, could result in the inability of the flightcrew to maintain 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 757-25A0319 RB, dated March 24, 2023, do all applicable actions identified in, and in accordance with, the Accomplishment Instructions of Boeing Alert Requirements Bulletin 757-25A0319 RB, dated March 24, 2023. Note 1 to paragraph (g): Guidance for accomplishing the actions required by this AD can be found in Boeing Alert Service Bulletin 757-25A0319, dated March 24, 2023, which is referred to in Boeing Alert Requirements Bulletin 757-25A0319 RB, dated March 24, 2023. (h) Exceptions to Service Information Specifications Where the Compliance Time columns of the tables in the “Compliance” paragraph of Boeing Alert Requirements Bulletin 757-25A0319 RB, dated March 24, 2023, use the phrase “the original issue date of Requirements Bulletin 757-25A0319 RB,” this AD requires replacing those words with “the effective date of this AD.” (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 the 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: 
                        *9-ANM-LAACO-AMOC-Requests@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 Katherine Venegas, Aviation Safety Engineer, FAA, 2200 South 216th St., Des Moines, WA 98198; telephone: 562-627-5353; email: 
                        *Katherine.Venegas@faa.gov.* (2) Service information identified in this AD that is not incorporated by reference is available at the addresses specified in paragraphs (k)(3) and (4) of this AD. (k) Material Incorporated by Reference (1) The Director of the Federal Register approved the incorporation by reference (IBR) of the service information listed in this paragraph under 5 U.S.C. 552(a) and 1 CFR part 51. (2) You must use this service information as applicable to do the actions required by this AD, unless the AD specifies otherwise. (i) Boeing Alert Requirements Bulletin 757-25A0319 RB, dated March 24, 2023. (ii) [Reserved] (3) For service information 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 service information 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/ibr-locationsoremailfr.inspection@nara.gov.* Issued on October 19, 2023. Caitlin Locke, Director, Compliance & Airworthiness Division, Aircraft Certification Service.


[FR Doc. 2023-23521 Filed 10-25-23; 8:45 am] BILLING CODE 4910-13-P