88 FR 138 pgs. 46679-46681 - Airworthiness Directives; The Boeing Company Airplanes
Type: RULEVolume: 88Number: 138Pages: 46679 - 46681
Pages: 46679, 46680, 46681Docket number: [Docket No. FAA-2023-0432; Project Identifier AD-2022-01384-T; Amendment 39-22457; AD 2023-11-11]
FR document: [FR Doc. 2023-15297 Filed 7-19-23; 8:45 am]
Agency: Transportation Department
Sub Agency: Federal Aviation Administration
Official PDF Version: PDF Version
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DEPARTMENT OF TRANSPORTATION
Federal Aviation Administration
14 CFR Part 39
[Docket No. FAA-2023-0432; Project Identifier AD-2022-01384-T; Amendment 39-22457; AD 2023-11-11]
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 all The Boeing Company Model 747-8 and 747-8F series airplanes. This AD was prompted by reports of cracks in stringers, common to the end fittings, forward and aft of the pressure bulkhead at station (STA) 2360 at multiple stringer locations. This AD requires repetitive inspections of stringer sidewalls and certain stringer assemblies, common to the end fittings, forward and aft of the pressure bulkhead at STA 2360 for any crack, and applicable on-condition actions. The FAA is issuing this AD to address the unsafe condition on these products.
DATES:
This AD is effective August 24, 2023.
The Director of the Federal Register approved the incorporation by reference of a certain publication listed in this AD as of August 24, 2023.
ADDRESSES:
AD Docket: You may examine the AD docket at regulations.gov under Docket No. FAA-2023-0432; 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 service information identified in this final rule, 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 Street, 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-2023-0432.
FOR FURTHER INFORMATION CONTACT:
Stefanie Roesli, Aviation Safety Engineer, FAA, 2200 South 216th Street, Des Moines, WA 98198; phone: 206-231-3964; email: stefanie.n.roesli@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 all The Boeing Company Model 747-8 and 747-8F series airplanes. The NPRM published in the Federal Register on April 6, 2023 (88 FR 20431). The NPRM was prompted by reports of cracks in the stringers, common to the end fittings, forward and aft of the pressure bulkhead at STA 2360. An investigation found that during airplane assembly, un-shimmed or incorrectly shimmed gaps, which were larger than engineering requirements, caused excessive and sustained internal tensile stresses and resulted in stress corrosion cracking in the stringers. In the NPRM, the FAA proposed to require repetitive inspections of stringer sidewalls and certain stringer assemblies, common to the end fittings, forward and aft of the pressure bulkhead at STA 2360 for any crack, and applicable on-condition actions. This condition, if not addressed, could result in an undetected crack in the stringers, resulting in the inability of a structural element to sustain limit load which could adversely affect the structural integrity of the airplane.
Discussion of Final Airworthiness Directive
Comments
The FAA received comments from Boeing and an individual who supported the NPRM without change.
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.
Related Service Information Under 1 CFR Part 51
The FAA reviewed Boeing Alert Requirements Bulletin 747-53A2910 RB, dated September 21, 2022. This service information specifies procedures for repetitive low frequency eddy current (LFEC) and high frequency eddy current (HFEC) inspections of the stringer sidewalls; repetitive detailed inspections of certain stringer assemblies; and applicable on-condition actions. On-condition actions include repair. 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 section.
Costs of Compliance
The FAA estimates that this AD affects 44 airplanes of U.S. registry. The FAA estimates the following costs to comply with this AD:
| Action | Labor cost | Parts cost | Cost per product | Cost on U.S. operators |
|---|---|---|---|---|
| Inspection of stringers | Up to 110 work-hours × $85 per hour = Up to $9,350 per inspection cycle | $0 | Up to $9,350 per inspection cycle | Up to $411,400 per inspection cycle. |
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The FAA estimates the following costs to do any necessary repairs that would be required based on the results of the inspection. The FAA has no way of determining the number of aircraft that might need this repair:
| Action | Labor cost | Parts cost | Cost per product |
|---|---|---|---|
| Repair of a cracked stringer | 13 work-hours × $85 per hour = $1,105 | $600 | $1,705 |
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
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:
2023-11-11 The Boeing Company: Amendment 39-22457; Docket No. FAA-2023-0432; Project Identifier AD-2022-01384-T.
(a) Effective Date
This airworthiness directive (AD) is effective August 24, 2023.
(b) Affected ADs
None.
(c) Applicability
This AD applies to all The Boeing Company Model 747-8 and 747-8F series airplanes, certificated in any category.
(d) Subject
Air Transport Association (ATA) of America Code: 53, Fuselage.
(e) Unsafe Condition
This AD was prompted by reports of cracks in the stringers, common to the end fittings, forward and aft of the pressure bulkhead at station (STA) 2360 at multiple stringer locations. The FAA is issuing this AD to address an undetected crack in the stringers. The unsafe condition, if not addressed, could result in the inability of a structural element to sustain limit load which could adversely affect the structural integrity of the airplane.
(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 747-53A2910 RB, dated September 21, 2022, do all applicable actions identified in, and in accordance with, the Accomplishment Instructions of Boeing Alert Requirements Bulletin 747-53A2910 RB, dated September 21, 2022.
Note 1 to paragraph (g):
Guidance for accomplishing the actions required by this AD can be found in Boeing Alert Service Bulletin 747-53A2910, dated September 21, 2022, which is referred to in Boeing Alert Requirements Bulletin 747-53A2910 RB, dated September 21, 2022.
(h) Exceptions to Service Information Specifications
(1) Where the Compliance Time columns of the tables in the "Compliance" paragraph of Boeing Alert Requirements Bulletin 747-53A2910 RB, dated September 21, 2022, use the phrase "the original issue date of Requirements Bulletin 747-53A2910 RB," this AD requires using "the effective date of this AD."
(2) Where Boeing Alert Requirements Bulletin 747-53A2910 RB, dated September 21, 2022, specifies contacting Boeing for repair instructions: This AD requires doing the repair using a method approved in accordance with the procedures specified in paragraph (i) 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 certification office, send it to the attention of the person identified in paragraph (j)(1) of this AD. Information may be emailed to: 9-ANM-Seattle-ACO-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 Stefanie Roesli, Aviation Safety Engineer, FAA, 2200 South 216th Street, Des Moines, WA 98198; phone: 206-231-3964; email: stefanie.n.roesli@faa.gov.
[top] (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 747-53A2910 RB, dated September 21, 2022.
(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 Street, Des Moines, WA. For information on the availability of this material at the FAA, call 206-231-3195.
(5) You may view this service information that is incorporated by reference at the National Archives and Records Administration (NARA). For information on the availability of this material at NARA, fr.inspection@nara.gov, or go to: www.archives.gov/federal-register/cfr/ibr-locations.html.
Issued on June 7, 2023.
Gaetano A. Sciortino,
Acting Director, Compliance & Airworthiness Division, Aircraft Certification Service.
[FR Doc. 2023-15297 Filed 7-19-23; 8:45 am]
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