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 Department of Transportation Federal Aviation Administration 14 CFR Part 39
[Docket No. FAA-2024-1478; Project Identifier MCAI-2023-01216-T; Amendment 39-22831; AD 2024-17-06]
RIN 2120-AA64
 AGENCY: Federal Aviation Administration (FAA), DOT.
 ACTION: Final rule.
 SUMMARY: The FAA is adopting a new airworthiness directive (AD) for all BAE Systems (Operations) Limited Model BAe 146 and Avro 146-RJ series airplanes. This AD was prompted by a report of cracking on the radius of the rib 0 forward longeron at a certain frame. This AD requires a one-time inspection for defects of the radius, and repair if necessary. The FAA is issuing this AD to address the unsafe condition on these products.
 DATES: This AD is effective November 4, 2024. The Director of the Federal Register approved the incorporation by reference of a certain publication listed in this AD as of November 4, 2024.
 ADDRESSES:  *AD Docket:*
                         You may examine the AD docket at 
                        *regulations.gov*
                         under Docket No. FAA-2024-1478; 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, the mandatory continuing airworthiness information (MCAI), 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 BAE Systems material identified in this AD, contact BAE Systems (Operations) Limited, Customer Information Department, Prestwick International Airport, Ayrshire, KA9 2RW, Scotland, United Kingdom; telephone +44 1292 675207; fax +44 1292 675704; email*RApublications@baesystems.com;*
                         website 
                        *baesystems.com/en/our-company/our-businesses/regional-aircraft/about-us.*
                    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-2024-1478.
 FOR FURTHER INFORMATION CONTACT: Todd Thompson, Aviation Safety Engineer, FAA, 1600 Stewart Avenue, Suite 410, Westbury, NY 11590; telephone 206-231-3228; email 
                        *todd.thompson@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 BAE Systems (Operations) Limited Model BAe 146 and Avro 146-RJ series airplanes. The NPRM published in the 
                    **Federal Register**
                     on June 6, 2024 (89 FR 48348). The NPRM was prompted by AD G-2023-0006, dated November 24, 2023 (referred to after this as the MCAI), issued by the Civil Aviation Authority (CAA), which is the aviation authority for the United Kingdom (UK). The MCAI states that an operator reported that during routine maintenance, cracking was found on the radius of the rib 0 forward longeron at frame 26. The cracking initiated close to a local blend in the radius. Failure of the rib 0 forward longeron could lead to structural failure of adjacent structure, leading to failure of the fuselage skin, and could result in rapid decompression and possible loss of the airplane. In the NPRM, the FAA proposed to require a one-time inspection for defects of the radius, and repair if necessary. The FAA is issuing this AD to address the unsafe condition on these products. You may examine the MCAI in the AD docket at 
                    *regulations.gov*
                     under Docket No. FAA-2024-1478. Discussion of Final Airworthiness Directive Comments The FAA received no comments on the NPRM or on the determination of the cost to the public. Conclusion This product has been approved by the aviation authority of another country and is approved for operation in the United States. Pursuant to the FAA's bilateral agreement with this State of Design Authority, it has notified the FAA of the unsafe condition described in the MCAI referenced above. The FAA reviewed the relevant data and determined that air safety requires adopting this AD as proposed. Accordingly, the FAA is issuing this AD to address the unsafe condition on this product. 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 BAE Systems (Operations) Limited Inspection Service Bulletin ISB.53-249, dated August 25, 2023. This material specifies procedures for performing a detailed inspection for any defects (rough edges, nicks, or visible cracking) and for any evidence of blending or undercutting of the radius and flanges of the rib 0 forward longeron at frame 26, performing a high frequency eddy current (HFEC) inspection of the radius of the rib 0 forward longeron at frame 26, and obtaining and following repair instructions. This material is reasonably available because the interested parties 
                    ( print page 79424)
                    have access to it through their normal course of business or by the means identified in the 
                    **ADDRESSES**
                     section. Interim Action The FAA considers that this AD is an interim action. If final action is later identified, the FAA might consider further rulemaking then. Costs of Compliance The FAA estimates that this AD affects 20 airplanes of U.S. registry. The FAA estimates the following costs to comply with this AD: Estimated Costs for Required Actions
Labor cost
Parts cost
Cost per 
                             product
Cost on U.S. operators2 work-hours × $85 per hour = $170
$0
$170
$3,400
 The FAA has received no definitive data on which to base the cost estimates for the on-condition repairs specified in this AD. 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
 2.The FAA amends § 39.13 by adding the following new airworthiness directive: **2024-17-06 BAE Systems (Operations) Limited:**
                             Amendment 39-22831; Docket No. FAA-2024-1478; Project Identifier MCAI-2023-01216-T. (a) Effective Date This airworthiness directive (AD) is effective November 4, 2024. (b) Affected ADs None. (c) Applicability This AD applies to all BAE Systems (Operations) Limited airplanes identified in paragraphs (c)(1) and (2) of this AD, certificated in any category. (1) Model BAe 146-100A, -200A, and -300A airplanes. (2) Model Avro 146-RJ70A, -RJ85A, and -RJ100A airplanes. (d) Subject Air Transport Association (ATA) of America Code 53, Fuselage. (e) Unsafe Condition This AD was prompted by a report of cracking on the radius of the rib 0 forward longeron at frame 26. The FAA is issuing this AD to address cracking of the radius of the rib 0 forward longeron at frame 26. The unsafe condition, if not addressed, could result in failure of the rib 0 forward longeron, which could lead to failure of an adjacent structure, leading to failure of the fuselage skin, and could result in rapid decompression and possible loss of the airplane. (f) Compliance Comply with this AD within the compliance times specified, unless already done. (g) Inspection and Corrective Actions Within 4 months after the effective date of this AD, do a visual and a high frequency eddy current inspection for defects of the radius of the rib 0 forward longeron at frame 26, in accordance with the Accomplishment Instructions of BAE Systems (Operations) Limited Inspection Service Bulletin ISB.53-249, dated August 25, 2023. If any cracking or defects are found, repair before further flight, in accordance with a method approved by the Manager, International Validation Branch, FAA; or the United Kingdom Civil Aviation Authority (UK CAA); or BAE Systems (Operations) Limited's UK CAA's Design Organization Approval (DOA). If the method is approved by the DOA, the approval must include the DOA-authorized signature. (h) Reporting Requirement Report positive inspection results at the applicable time specified in paragraph (h)(1) or (2) of this AD using the Inspection Report form in Appendix 1 of BAE Systems (Operations) Limited Inspection Service Bulletin ISB.53-249, dated August 25, 2023. (1) If the inspection was done on or after the effective date of this AD: Submit the report within 30 days after the inspection. (2) If the inspection was done before the effective date of this AD: Submit the report within 30 days after the effective date of this AD. (i) 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 (j) of this AD. Information may be emailed to: 
                            *AMOC@faa.gov.*
                             Before using any approved AMOC, notify your appropriate 
                            ( print page 79425)
                            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 the UK CAA; or BAE Systems (Operations) Limited's UK CAA's DOA. If approved by the DOA, the approval must include the DOA-authorized signature. (j) 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.* (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 this AD specifies otherwise. (i) BAE Systems (Operations) Limited Inspection Service Bulletin ISB.53-249, dated August 25, 2023. (ii) [Reserved] (3) For BAE Systems material identified in this AD, contact BAE Systems (Operations) Limited, Customer Information Department, Prestwick International Airport, Ayrshire, KA9 2RW, Scotland, United Kingdom; telephone +44 1292 675207; fax +44 1292 675704; email 
                            *RApublications@baesystems.com;*
                             website 
                            *baesystems.com/en/our-company/our-businesses/regional-aircraft/about-us.* (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/​ibr-locations*
                             or email 
                            *fr.inspection@nara.gov.* Issued on August 22, 2024. Victor Wicklund, Deputy Director, Compliance & Airworthiness Division, Aircraft Certification Service.


[FR Doc. 2024-22319 Filed 9-27-24; 8:45 am] BILLING CODE 4910-13-P