Airworthiness Directives; MHI RJ Aviation ULC (Type Certificate Previously Held by Bombardier Inc.) Airplanes, 13278-13284 [2025-04720]

Download as PDF 13278 Federal Register / Vol. 90, No. 54 / Friday, March 21, 2025 / Rules and Regulations FIGURE 1 TO PARAGRAPH (j)—SYSTEM AIRWORTHINESS LIMITATIONS SYSTEM AIRWORTHINESS LIMITATION No. 2 FAN BLADE OUT CONDITIONS All aircraft must install the following modifications: (1) engines inlets with new spacer design and increased fastener capability (2) fan cowls with new radial restraint fitting hooks, new radial restraint clips, and an external doubler at the starter vent (3) fan cowl support beam fastener changes (except for 737–900ER aircraft, because the fan cowl support beam fastener changes are already incorporated). All aircraft that have not incorporated these modifications cannot operate past July 31, 2028 unless upgraded to new hardware that is fully compliant to §§ 25.901(c) and Appendix K25.1.1 to Part 25. Boeing will release all service data to allow retrofit of hardware updates to the CFM56–7B nacelle prior to that date. SYSTEM AIRWORTHINESS LIMITATION No. 3 FAN BLADE OUT CONDITIONS All aircraft delivered without the Performance Improvement Package (PIP) must install engine exhaust nozzle structural stiffening elements. All aircraft that have not incorporated these modifications cannot operate past July 31, 2028 unless upgraded to new hardware that is fully compliant to §§ 25.901(c) and Appendix K25.1.1 to Part 25. Boeing will release all service data to allow retrofit of hardware updates to the CFM56– 7B nacelle prior to that date. SYSTEM AIRWORTHINESS LIMITATION No. 4 ENGINE NACELLE MAINTENANCE ERRORS All aircraft must incorporate solutions to address potential maintenance errors, e.g., the failure to completely latch the fan cowl or the can cowl integrated drive generator (IDG) door. All aircraft that have not incorporated changes to become fully compliance with §§ 25.901(c) and Appendix K25.1.1 to Part 25 cannot be operated past December 31, 2029. (m) Material Incorporated by Reference (k) 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 (l)(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. khammond on DSK9W7S144PROD with RULES (l) Related Information (1) For more information about this AD, contact Luis Cortez-Muniz, Aviation Safety Engineer, FAA, 2200 South 216th St., Des Moines, WA 98198; telephone: 206–231– 3958; email: luis.a.cortez-muniz@faa.gov. (2) For Collins material identified in this AD that is not incorporated by reference, contact Collins Aerospace, 15701 West 95th Street, Lenexa, KS 66219; email ISPublications@collins.com; website tpi.beaerospace.com/Authentication. (3) Boeing material identified in this AD that is not incorporated by reference is available at the address specified in paragraph (m)(3) this AD. VerDate Sep<11>2014 16:00 Mar 20, 2025 Jkt 265001 (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. (3) The following material was approved for IBR on April 8, 2025 (90 FR 11109, March 4, 2025). (i) Boeing Special Attention Requirements Bulletin 737–71–1937 RB, Revision 1, dated June 27, 2024. (ii) [Reserved] (4) 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. (5) 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. (6) 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 March 17, 2025. Victor Wicklund, Deputy Director, Integrated Certificate Management Division, Aircraft Certification Service. [FR Doc. 2025–04782 Filed 3–20–25; 8:45 am] BILLING CODE 4910–13–P PO 00000 Frm 00008 Fmt 4700 Sfmt 4700 DEPARTMENT OF TRANSPORTATION Federal Aviation Administration 14 CFR Part 39 [Docket No. FAA–2024–1896; Project Identifier MCAI–2023–00978–T; Amendment 39–22966; AD 2025–04–08] RIN 2120–AA64 Airworthiness Directives; MHI RJ Aviation ULC (Type Certificate Previously Held by Bombardier Inc.) Airplanes Federal Aviation Administration (FAA), DOT. ACTION: Final rule. AGENCY: The FAA is adopting a new airworthiness directive (AD) for certain MHI RJ Aviation ULC Model CL–600– 2B19 (Regional Jet Series 100 and 440), CL–600–2C10 (Regional Jet Series 700, 701, and 702), CL–600–2C11 (Regional Jet Series 550), CL–600–2D15 (Regional Jet Series 705), CL–600–2D24 (Regional Jet Series 900), and CL–600–2E25 (Regional Jet Series 1000) airplanes. This AD was prompted by the determination that radio altimeters cannot be relied upon to perform their intended function if they experience interference from wireless broadband operations in the 3.7–3.98 GHz frequency band (5G C-Band). This AD requires installing a new radio frequency (RF) bandpass filter on the coaxial line between the radio altimeter and the receive antenna in the aft equipment compartment. The FAA is issuing this AD to address the unsafe condition on these products. DATES: This AD is effective April 25, 2025. SUMMARY: E:\FR\FM\21MRR1.SGM 21MRR1 Federal Register / Vol. 90, No. 54 / Friday, March 21, 2025 / Rules and Regulations The Director of the Federal Register approved the incorporation by reference of certain publications listed in this AD as of April 25, 2025. ADDRESSES: AD Docket: You may examine the AD docket at regulations.gov under Docket No. FAA–2024–1896; 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 MHI RJ material identified in this AD, contact MHI RJ Aviation Group, Customer Response Center, 3655 Ave. des Grandes-Tourelles, Suite 110, Boisbriand, Québec J7H 0E2 Canada; North America toll-free telephone 833– 990–7272 or direct-dial telephone 450– 990–7272; fax 514–855–8501; email thd.crj@mhirj.com; website mhirj.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–2024–1896. FOR FURTHER INFORMATION CONTACT: Steven Dzierzynski, Aviation Safety Engineer, FAA, 1600 Stewart Avenue, Suite 410, Westbury, NY 11590; telephone 516–228–7300; email 9-avsnyaco-cos@faa.gov. SUPPLEMENTARY INFORMATION: khammond on DSK9W7S144PROD with RULES Background The FAA issued AD 2023–10–02, Amendment 39–22438 (88 FR 34065, May 26, 2023) (AD 2023–10–02) to address the effect of interference from wireless broadband operations in the 5G C-Band on all transport and commuter category airplanes equipped with a radio altimeter. AD 2023–10–02 was prompted by a determination that radio altimeters cannot be relied upon to perform their intended function if they experience interference from wireless broadband operations in the 5G C-Band. AD 2023–10–02 requires revising the limitations section of the existing airplane flight manual to incorporate limitations prohibiting transport and commuter category airplanes from performing certain low-visibility landing operations at any airport unless they have upgraded their radio VerDate Sep<11>2014 16:00 Mar 20, 2025 Jkt 265001 altimeters. Transport Canada, which is the aviation authority for Canada, issued corresponding Transport Canada AD CF–2023–46, dated June 30, 2023, to require similar limitations on flight operations requiring radio altimeter data in U.S. airspace affected by 5G C-Band wireless signals. The FAA subsequently issued a notice of proposed rulemaking (NPRM) to amend 14 CFR part 39 by adding an AD that would apply to certain MHI RJ Aviation ULC Model CL–600–2B19 (Regional Jet Series 100 and 440), CL– 600–2C10 (Regional Jet Series 700, 701, and 702), CL–600–2C11 (Regional Jet Series 550), CL–600–2D15 (Regional Jet Series 705), CL–600–2D24 (Regional Jet Series 900), and CL–600–2E25 (Regional Jet Series 1000) airplanes. The NPRM published in the Federal Register on September 9, 2024 (89 FR 73009). The NPRM was prompted by AD CF–2023– 62R1, dated November 21, 2023, issued by Transport Canada, which is the aviation authority for Canada (referred to after this as the MCAI). The MCAI states that, in addition to the effects of 5G C-Band broadband interference identified in FAA AD 2023–10–02, MHI RJ has determined that 5G C-Band broadband interference can result in certain failure messages and aural alerts being inhibited longer than intended. Specifically, this can result in the inhibition of hydraulic system #3 and wing anti-ice overheat failure messages such that flightcrew are unable to perform appropriate airplane flight manual (AFM) procedures in the time needed to prevent loss of elevator control due to hydraulic system overheat and wing structural damage due to wing anti-ice system overheat. This condition, if not corrected, could result in delayed flightcrew response leading to loss of continued safe flight and landing. In the NPRM, the FAA proposed to require installing a new RF bandpass filter on the coaxial line between the radio altimeter and the receive antenna in the aft equipment compartment. When the airplane is modified as specified in this AD, the configuration with the RF bandpass filter installed has been determined to be ‘‘radio altimeter tolerant.’’ The FAA is issuing this AD because radio altimeter anomalies can result in the inhibition of certain failure messages such that the flightcrew are unable to perform appropriate airplane flight manual procedures in the time needed to prevent potential ignition hazard due to overheated hydraulic fluid circulating in the fuel tanks area, which may lead to loss of continued safe flight and landing, and/or structural deformation of the wing leading edge PO 00000 Frm 00009 Fmt 4700 Sfmt 4700 13279 which may reduce the safety margin (to stall). You may examine the MCAI in the AD docket at regulations.gov under Docket No. FAA–2024–1896. Discussion of Final Airworthiness Directive Comments The FAA received comments from Mesa Airlines, MHI RJ Aviation (MHI RJ), and an individual commenter. The following presents the comments received on the NPRM and the FAA’s response to each comment. Request To Refer To Revised Service Information MHI RJ and an individual commenter requested that the proposed AD be revised to refer to revised service bulletins. The individual commenter noted that MHI RJ Service Bulletin 670BA–34–054 is currently at Revision E. MHI RJ stated that the original issue and Revisions A, B, C, D, and E of MHI RJ Service Bulletin 670BA–34–054; and Revisions D and E of MHI RJ Service Bulletin 601R–34–152 should be listed as methods of compliance for the actions required by the proposed AD. MHI RJ also requested that all acceptable revisions of the referenced service information be added to paragraph (n) of the proposed AD. The FAA agrees to refer to the latest revisions of the service information. MHI RJ Service Bulletin 601R–34–152, Revision E, dated June 29, 2023, includes minor editorial changes (adding reference to an FAA AD and additional reference documents; and revising recommended compliance times, though the FAA notes that the compliance times in this AD take precedence over those in the service information). Those changes do not have an effect on the technical content and no additional work is necessary for operators that incorporated MHI RJ Service Bulletin 601R–34–152, Revision D, dated May 11, 2023. MHI RJ Service Bulletin 670BA–34–054, dated February 20, 2023; Revision A, dated February 28, 2023; Revision B, dated March 28, 2023; Revision C, dated June 29, 2023; Revision D, dated August 31, 2023; and Revision E, dated January 11, 2024; contain minor editorial revisions that do not have an effect on the technical content or require additional work for operators that incorporated earlier revisions. Therefore, the FAA has revised this AD to refer to MHI RJ Service Bulletin 670BA–34–054, Revision E, dated January 11, 2024; and MHI RJ Service Bulletin 601R–34–152, Revision E, dated June 29, 2023. E:\FR\FM\21MRR1.SGM 21MRR1 13280 Federal Register / Vol. 90, No. 54 / Friday, March 21, 2025 / Rules and Regulations Regarding the request to cite all acceptable revisions of the service information in paragraph (n) of this AD, the FAA notes that paragraph (n) of this AD identifies only material that is to be incorporated by reference in the AD, and this AD requires and incorporates by reference only Revision E of the service bulletins, as specified in paragraphs (h), (i), and (j) of this AD. khammond on DSK9W7S144PROD with RULES Requests To Revise Credit for Previous Actions An individual commenter requested that the FAA revise paragraph (k) of the proposed AD to include credit for actions performed using the original issue or Revisions A, B, C, or D of MHI RJ Service Bulletin 670BA–34–054. MHI RJ requested revising the conditional credit specified in the introductory text of paragraph (k) of the proposed AD to specify an additional document. MHI RJ noted that credit is conditional on operators installing the electrical idents for coax cables using Part G of MHI RJ Service Bulletin 601R–34–152, which is included only in Revisions D and E of that service information. MHI RJ also stated that some operators may have used, and should be granted credit for, Service Non-Incorporated Engineering Order (SNIEO) KCM601R53009–S01, which provides instructions for fabricating and installing electrical idents, and which is equivalent to Part G of Revision D and Revision E of MHI RJ Service Bulletin 601R–34–152. The FAA agrees with the commenters’ requests. The FAA has revised paragraph (k) of this AD as follows: • Revised paragraph (k)(1) of this AD to refer to MHI RJ Service Bulletin 601R–34–152, Revision E, dated June 29, 2023. • Added paragraph (k)(2) of this AD to provide credit for actions done using certain revisions of MHI RJ Service Bulletin 601R–34–152 provided that idents were installed using SNIEO KCM601R53009–S01 or MHI RJ Service Bulletin 601R–34–152, Revision D, dated May 11, 2023. • Added paragraph (k)(3) of this AD to provide credit for MHI RJ Service Bulletin 601R–34–152, Revision D, dated May 11, 2023. • Added paragraph (k)(4) of this AD to provide credit for the original issue and Revisions A, B, C, or D of MHI RJ Service Bulletin 670BA–34–054. Request To Clarify Applicability Mesa Airlines requested clarification of the affected Model CL–600–2D24 (Regional Jet Series 900) airplanes in paragraph (c) of the proposed AD. The proposed AD identified manufacturer serial numbers (MSNs) 15001 through VerDate Sep<11>2014 16:00 Mar 20, 2025 Jkt 265001 15990, which, according to Mesa Airlines, is all Model CL–600–2D24 airplanes. The commenter noted, however, that the effectivity of MHI RJ Service Bulletin 670BA–34–054, dated February 20, 2023, is limited to selected MSNs. That service bulletin was cited in paragraph (i) of the proposed AD as the appropriate source of service information for installing the RF bandpass filter for the specified airplanes including Model CL–600– 2D24 airplanes. The FAA provides the following clarification. The effectivity in MHI RJ Service Bulletin 670BA–34–054, dated February 20, 2023, is limited to selected MSNs. According to MHI RJ, the initial issue of this service bulletin was intended for those operators interested in purchasing the modification, so the MSNs listed in that service bulletin were confirmed to be committed for purchase of the modification kits. Rather than revising the service bulletin effectivity each time a new MSN needed to be added, MHI RJ later decided to make the service bulletin applicable to all MSNs. Therefore, the effectivity in subsequent service bulletin revisions includes all MSNs. As stated previously, this AD has been changed to refer to MHI RJ Service Bulletin 670BA–34–054, Revision E, dated January 11, 2024, for the required actions for airplanes including Model CL–600–2D24 airplanes. Request To Clarify Unsafe Condition The Background section of the NPRM and paragraph (e) (‘‘Unsafe Condition’’) of the proposed AD stated that the FAA proposed the AD because radio altimeter anomalies can result in the inhibition of certain failure messages such that the flightcrew are unable to perform appropriate AFM procedures in the time needed to prevent ‘‘loss of elevator control due to hydraulic system overheat and wing structural damage due to wing anti-ice system overheat,’’ which could result in ‘‘delayed flightcrew response leading to loss of continued safe flight and landing.’’ MHI RJ recommended that the FAA revise the proposed AD to state that the intent is rather to prevent ‘‘potential ignition hazard due to overheated hydraulic fluid circulating in the fuel tanks area, which may lead to loss of continued safe flight and landing, and/or structural deformation of the wing leading edge which may reduce the safety margin (to stall).’’ The FAA agrees with MHI RJ’s proposed text, which better clarifies the radio altimeter anomalies that can result in the inhibition of certain failure messages. The Background section and PO 00000 Frm 00010 Fmt 4700 Sfmt 4700 paragraph (e) of this AD have been revised accordingly. Request To Remove Statement Related to Unsafe Condition The Background section of the NPRM stated that MHI RJ determined that 5G C-Band broadband interference can result in certain failure messages and aural alerts being inhibited longer than intended. The Background then included the following statement: Specifically, this can result in the inhibition of hydraulic system #3 and wing anti-ice overheat failure messages such that flightcrew are unable to perform appropriate airplane flight manual (AFM) procedures in the time needed to prevent loss of elevator control due to hydraulic system overheat and wing structural damage due to wing anti-ice system overheat. This condition, if not corrected, could result in delayed flightcrew response leading to loss of continued safe flight and landing. MHI RJ recommended removing the quoted statement because that content is not included in Canadian AD CF–2023– 46, and it is unnecessary and misleading. The FAA agrees to clarify. The FAA acknowledges that the specified text is not included in Transport Canada AD CF–2023–46. However, the FAA has determined that the added text provides additional details for a more comprehensive background of the unsafe condition identified in this final rule. Request To Revise a Compliance Time MHI RJ recommended changing paragraph (j) of the proposed AD, which proposed to require installing an RF bandpass filter on Model CL–600–2E25 airplanes ‘‘before the next flight in the contiguous U.S. airspace’’ after the effective date of the AD. MJI RJ recommended removing ‘‘in the contiguous U.S. airspace’’ because the proposed AD would apply to U.S.registered airplanes operating in any airspace. The FAA disagrees with MHI RJ’s request to change this compliance time language for Model CL–600–2E25 airplanes. The language has been retained in paragraph (j) of this AD to require compliance ‘‘before the next flight in the contiguous U.S. airspace’’ for Model CL–600–2E25 airplanes because none of those affected airplanes are currently flying in the U.S, but the AD requirements will apply if an affected airplane is placed on the U.S. Registry and flown in the contiguous U.S. The FAA has not changed paragraph (j) of this AD as a result of this comment. E:\FR\FM\21MRR1.SGM 21MRR1 Federal Register / Vol. 90, No. 54 / Friday, March 21, 2025 / Rules and Regulations 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, considered the 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 this product. Except for minor editorial changes, and any other changes described previously, 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 MHI RJ Service Bulletins 601R–34–152, Revision E, dated June 29, 2023, and 670BA–34– 054, Revision E, dated January 11, 2024. This material specifies procedures for installing a new RF bandpass filter on the coaxial line between the radio altimeter and the receive antenna in the aft equipment compartment. These documents are distinct since they apply 13281 to different airplane models. 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 up to 873 airplanes of U.S. registry. However, many of these airplanes may already have a bandpass filter installed in compliance with AD 2023–10–02 and would not incur any additional costs to comply with this AD. The FAA estimates the following costs to comply with this AD: ESTIMATED COSTS Labor cost Parts cost 58 work-hours × $85 per hour = $4,930 ......................................................................... khammond on DSK9W7S144PROD with RULES 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, VerDate Sep<11>2014 16:00 Mar 20, 2025 Jkt 265001 $53,647 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(f), 40113, 44701. § 39.13 Cost per product $58,577 Cost on U.S. operators Up to $51,137,721. equipped with a radio altimeter and not determined to be a radio altimeter tolerant airplane as defined in paragraph (g) of this AD. (1) Model CL–600–2B19 (Regional Jet Series 100 and 440) airplanes, serial number (S/N) 7002 through 8113. (2) Model CL–600–2C10 (Regional Jet Series 700, 701, and 702) airplanes, S/N 10002 through 10999. (3) Model CL–600–2C11 (Regional Jet Series 550) airplanes, S/N 10002 through 10999. (4) Model CL–600–2D15 (Regional Jet Series 705) airplanes, S/N 15001 through 15990. (5) Model CL–600–2D24 (Regional Jet Series 900) airplanes, S/N 15001 through 15990. (6) Model CL–600–2E25 (Regional Jet Series 1000) airplanes, S/N 19013 through 19990. (d) Subject [Amended] 2. The FAA amends § 39.13 by adding the following new airworthiness directive: Air Transport Association (ATA) of America Code 34, Navigation. 2025–04–08 MHI RJ Aviation ULC (Type Certificate Previously Held by Bombardier Inc.): Amendment 39– 22966; Docket No. FAA–2024–1896; Project Identifier MCAI–2023–00978–T. This AD was prompted by the determination that radio altimeters cannot be relied upon to perform their intended function if they experience interference from wireless broadband operations in the 3.7– 3.98 GHz frequency band (5G C-Band). The FAA is issuing this AD because radio altimeter anomalies can result in the inhibition of certain failure messages such that the flightcrew are unable to perform appropriate airplane flight manual procedures in the time needed to prevent potential ignition hazard due to overheated hydraulic fluid circulating in the fuel tanks area, which may lead to loss of continued safe flight and landing, and/or structural deformation of the wing leading edge which may reduce the safety margin (to stall). ■ (a) Effective Date This airworthiness directive (AD) is effective April 25, 2025. (b) Affected ADs None. (c) Applicability This AD applies to the MHI RJ Aviation ULC (Type Certificate previously held by Bombardier Inc.) airplanes identified in paragraphs (c)(1) through (6) of this AD, certificated in any category, that are PO 00000 Frm 00011 Fmt 4700 Sfmt 4700 (e) Unsafe Condition E:\FR\FM\21MRR1.SGM 21MRR1 Federal Register / Vol. 90, No. 54 / Friday, March 21, 2025 / Rules and Regulations (f) Compliance Comply with this AD within the compliance times specified, unless already done. (g) Definitions For purposes of this AD, a ‘‘radio altimeter tolerant airplane’’ is one for which the radio khammond on DSK9W7S144PROD with RULES (2) Tolerance to radio altimeter interference, for the spurious emissions (4.2– 4.4 GHz), at or above the PSD curve threshold VerDate Sep<11>2014 16:00 Mar 20, 2025 Jkt 265001 altimeter, as installed, demonstrates the tolerances specified in paragraphs (g)(1) and (2) of this AD, using a method approved by the FAA. No actions are required by this AD for radio altimeter tolerant airplanes. (1) Tolerance to radio altimeter interference, for the fundamental emissions (3.7–3.98 GHz), at or above the power spectral density (PSD) curve threshold specified in figure 1 to paragraph (g)(1) of this AD. specified in figure 2 to paragraph (g)(2) of this AD. Figure 2 to Paragraph (g)(2)—Spurious Effective Isotropic PSD at Outside Interface of Airplane Antenna PO 00000 Frm 00012 Fmt 4700 Sfmt 4700 Figure 1 to Paragraph (g)(1)—Fundamental Effective Isotropic PSD at Outside Interface of Airplane Antenna BILLING CODE 4910–13–P E:\FR\FM\21MRR1.SGM 21MRR1 ER21MR25.000</GPH> 13282 Federal Register / Vol. 90, No. 54 / Friday, March 21, 2025 / Rules and Regulations (h) Filter Installation: Model CL–600–2B19 For Model CL–600–2B19 airplanes: Within 2,300 flight hours or 12 months after the effective date of this AD, whichever occurs first, install a radio frequency (RF) bandpass filter on each radio altimeter in accordance with the applicable parts of the Accomplishment Instructions in MHI RJ Service Bulletin 601R–34–152, Revision E, dated June 29, 2023. Alternatively, airplanes with a dual radio altimeter configuration may comply with this paragraph by installing an RF bandpass filter on one radio altimeter and deactivating the second radio altimeter in VerDate Sep<11>2014 16:00 Mar 20, 2025 Jkt 265001 accordance with the applicable parts of the Accomplishment Instructions in MHI RJ Service Bulletin 601R–34–152, Revision E, dated June 29, 2023. (i) Filter Installation: Model CL–600–2C10, CL–600–2C11, CL–600–2D15, and CL–600– 2D24 For Model CL–600–2C10, CL–600–2C11, CL–600–2D15, and CL–600–2D24 airplanes: Within 2,100 flight hours or 12 months after the effective date of this AD, whichever occurs first, install an RF bandpass filter on each radio altimeter in accordance with the applicable parts of the Accomplishment Instructions in MHI RJ Service Bulletin PO 00000 Frm 00013 Fmt 4700 Sfmt 4700 670BA–34–054, Revision E, dated January 11, 2024. Alternatively, airplanes with a dual radio altimeter configuration may comply with this paragraph by installing an RF bandpass filter on one radio altimeter and deactivating the second radio altimeter in accordance with the applicable parts of the Accomplishment Instructions in MHI RJ Service Bulletin 670BA–34–054, Revision E, dated January 11, 2024. (j) Filter Installation: Model CL–600–2E25 For Model CL–600–2E25 airplanes: Before the next flight in the contiguous U.S. airspace after the effective date of this AD, install an RF bandpass filter on each radio altimeter in E:\FR\FM\21MRR1.SGM 21MRR1 ER21MR25.001</GPH> khammond on DSK9W7S144PROD with RULES BILLING CODE 4910–13–C 13283 13284 Federal Register / Vol. 90, No. 54 / Friday, March 21, 2025 / Rules and Regulations khammond on DSK9W7S144PROD with RULES accordance with the applicable parts of the Accomplishment Instructions in MHI RJ Service Bulletin 670BA–34–054, Revision E, dated January 11, 2024. (k) Credit for Previous Actions (1) For Model CL–600–2B19 airplanes: This paragraph provides credit for the actions required by paragraph (h) of this AD, if those actions were performed before the effective date of this AD using the material in paragraphs (k)(1)(i) through (iv) of this AD, provided the electrical idents for coax cables are installed using Part G of the Accomplishment Instructions in MHI RJ Service Bulletin 601R–34–152, Revision E, dated June 29, 2023, within the compliance time specified in paragraph (h) of this AD. (i) MHI RJ Service Bulletin 601R–34–152, dated February 14, 2023. (ii) MHI RJ Service Bulletin 601R–34–152, Revision A, dated February 28, 2023. (iii) MHI RJ Service Bulletin 601R–34–152, Revision B, dated March 28, 2023. (iv) MHI RJ Service Bulletin 601R–34–152, Revision C, dated April 20, 2023. (2) For Model CL–600–2B19 airplanes: This paragraph provides credit for the actions required by paragraph (h) of this AD, if those actions were performed before the effective date of this AD using the material in paragraphs (k)(2)(i) through (iv) of this AD, provided the electrical idents for coax cables were installed using Part G of the Accomplishment Instructions in MHI RJ Service Bulletin 601R–34–152, Revision D, dated May 11, 2023, or MHI RJ Service NonIncorporated Engineering Order (SNIEO) KCM601R53009–S01, dated May 2, 2023, prior to the effective date of this AD. (i) MHI RJ Service Bulletin 601R–34–152, dated February 14, 2023. (ii) MHI RJ Service Bulletin 601R–34–152, Revision A, dated February 28, 2023. (iii) MHI RJ Service Bulletin 601R–34–152, Revision B, dated March 28, 2023. (iv) MHI RJ Service Bulletin 601R–34–152, Revision C, dated April 20, 2023. (3) For Model CL–600–2B19 airplanes: This paragraph provides credit for the actions required by paragraph (h) of this AD, if those actions were performed before the effective date of this AD using MHI RJ Service Bulletin 601R–34–152, Revision D, dated May 11, 2023. (4) For Model CL–600–2C10, CL–600– 2C11, CL–600–2D15, CL–600–2D24, and CL– 600–2E25 airplanes: This paragraph provides credit for the actions required by paragraphs (i) and (j) of this AD, as applicable, if those actions were performed before the effective date of this AD using the material in paragraphs (k)(4)(i) through (v) of this AD. (i) MHI RJ Service Bulletin 670BA–34–054, dated February 20, 2023. (ii) MHI RJ Service Bulletin 670BA–34– 054, Revision A, dated February 28, 2023. (iii) MHI RJ Service Bulletin 670BA–34– 054, Revision B, dated March 28, 2023. (iv) MHI RJ Service Bulletin 670BA–34– 054, Revision C, dated June 29, 2023. (v) MHI RJ Service Bulletin 670BA–34– 054, Revision D, dated August 31, 2023. (l) Additional AD Provisions The following provisions also apply to this AD: VerDate Sep<11>2014 16:00 Mar 20, 2025 Jkt 265001 (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 (m)(1) 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 Transport Canada; or MHI RJ Aviation ULC’s Transport Canada Design Approval Organization (DAO). If approved by the DAO, the approval must include the DAO-authorized signature. (m) Additional Information (1) For more information about this AD, contact Steven Dzierzynski, Aviation Safety Engineer, FAA, 1600 Stewart Avenue, Suite 410, Westbury, NY 11590; telephone 516– 228–7300; email 9-avs-nyaco-cos@faa.gov. (2) Material identified in this AD that is not incorporated by reference is available at the address specified in paragraph (n)(3) of this AD. (n) Material Incorporated by Reference (1) The Director of the Federal Register approved the incorporation by reference 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) MHI RJ Service Bulletin 601R–34–152, Revision E, dated June 29, 2023. (ii) MHI RJ Service Bulletin 670BA–34– 054, Revision E, dated January 11, 2024. (3) For MHI RJ material identified in this AD, contact MHI RJ Aviation Group, Customer Response Center, 3655 Ave. des Grandes-Tourelles, Suite 110, Boisbriand, Québec J7H 0E2 Canada; North America tollfree telephone 833–990–7272 or direct-dial telephone 450–990–7272; fax 514–855–8501; email thd.crj@mhirj.com; website mhirj.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/ ibr-locations, or email fr.inspection@ nara.gov. PO 00000 Frm 00014 Fmt 4700 Sfmt 4700 Issued on February 18, 2025. Victor Wicklund, Deputy Director, Compliance & Airworthiness Division, Aircraft Certification Service. [FR Doc. 2025–04720 Filed 3–20–25; 8:45 am] BILLING CODE 4910–13–P DEPARTMENT OF HOMELAND SECURITY U.S. Customs and Border Protection 19 CFR Part 12 [CBP Dec. 25–02] RIN 1685–AA29 Extension of Import Restrictions on Certain Archaeological Material of Jordan U.S. Customs and Border Protection, Department of Homeland Security. ACTION: Final rule. AGENCY: This document amends the U.S. Customs and Border Protection (CBP) regulations to extend import restrictions on certain archaeological material from the Hashemite Kingdom of Jordan. The Principal Deputy Assistant Secretary for Educational and Cultural Affairs, United States Department of State, has made the requisite determinations for extending the import restrictions, which were originally imposed by CBP Decision 20– 02. These import restrictions are being extended pursuant to an exchange of diplomatic notes. The CBP regulations are being amended to reflect this further extension through January 14, 2030. DATES: Effective on March 21, 2025. FOR FURTHER INFORMATION CONTACT: For legal aspects, W. Richmond Beevers, Chief, Cargo Security, Carriers and Restricted Merchandise Branch, Regulations and Rulings, Office of Trade, (202) 325–0084, ototrrculturalproperty@cbp.dhs.gov. For operational aspects, Julie L. Stoeber, Chief, 1USG Branch, Trade Policy and Programs, Office of Trade, (202) 945– 7064, 1USGBranch@cbp.dhs.gov. SUPPLEMENTARY INFORMATION: SUMMARY: Background The Convention on Cultural Property Implementation Act (Pub. L. 97–446, 19 U.S.C. 2601 et seq.) (CPIA), which implements the 1970 United Nations Educational, Scientific and Cultural Organization (UNESCO) Convention on the Means of Prohibiting and Preventing the Illicit Import, Export and Transfer of Ownership of Cultural Property (823 E:\FR\FM\21MRR1.SGM 21MRR1

Agencies

[Federal Register Volume 90, Number 54 (Friday, March 21, 2025)]
[Rules and Regulations]
[Pages 13278-13284]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2025-04720]


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

DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2024-1896; Project Identifier MCAI-2023-00978-T; 
Amendment 39-22966; AD 2025-04-08]
RIN 2120-AA64


Airworthiness Directives; MHI RJ Aviation ULC (Type Certificate 
Previously Held by Bombardier Inc.) Airplanes

AGENCY: Federal Aviation Administration (FAA), DOT.

ACTION: Final rule.

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

SUMMARY: The FAA is adopting a new airworthiness directive (AD) for 
certain MHI RJ Aviation ULC Model CL-600-2B19 (Regional Jet Series 100 
and 440), CL-600-2C10 (Regional Jet Series 700, 701, and 702), CL-600-
2C11 (Regional Jet Series 550), CL-600-2D15 (Regional Jet Series 705), 
CL-600-2D24 (Regional Jet Series 900), and CL-600-2E25 (Regional Jet 
Series 1000) airplanes. This AD was prompted by the determination that 
radio altimeters cannot be relied upon to perform their intended 
function if they experience interference from wireless broadband 
operations in the 3.7-3.98 GHz frequency band (5G C-Band). This AD 
requires installing a new radio frequency (RF) bandpass filter on the 
coaxial line between the radio altimeter and the receive antenna in the 
aft equipment compartment. The FAA is issuing this AD to address the 
unsafe condition on these products.

DATES: This AD is effective April 25, 2025.

[[Page 13279]]

    The Director of the Federal Register approved the incorporation by 
reference of certain publications listed in this AD as of April 25, 
2025.

ADDRESSES: 
    AD Docket: You may examine the AD docket at regulations.gov under 
Docket No. FAA-2024-1896; 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 MHI RJ material identified in this AD, contact MHI RJ 
Aviation Group, Customer Response Center, 3655 Ave. des Grandes-
Tourelles, Suite 110, Boisbriand, Qu[eacute]bec J7H 0E2 Canada; North 
America toll-free telephone 833-990-7272 or direct-dial telephone 450-
990-7272; fax 514-855-8501; email mhirj.com">thd.crj@mhirj.com; website mhirj.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-2024-1896.

FOR FURTHER INFORMATION CONTACT: Steven Dzierzynski, Aviation Safety 
Engineer, FAA, 1600 Stewart Avenue, Suite 410, Westbury, NY 11590; 
telephone 516-228-7300; email [email protected].

SUPPLEMENTARY INFORMATION:

Background

    The FAA issued AD 2023-10-02, Amendment 39-22438 (88 FR 34065, May 
26, 2023) (AD 2023-10-02) to address the effect of interference from 
wireless broadband operations in the 5G C-Band on all transport and 
commuter category airplanes equipped with a radio altimeter. AD 2023-
10-02 was prompted by a determination that radio altimeters cannot be 
relied upon to perform their intended function if they experience 
interference from wireless broadband operations in the 5G C-Band. AD 
2023-10-02 requires revising the limitations section of the existing 
airplane flight manual to incorporate limitations prohibiting transport 
and commuter category airplanes from performing certain low-visibility 
landing operations at any airport unless they have upgraded their radio 
altimeters. Transport Canada, which is the aviation authority for 
Canada, issued corresponding Transport Canada AD CF-2023-46, dated June 
30, 2023, to require similar limitations on flight operations requiring 
radio altimeter data in U.S. airspace affected by 5G C-Band wireless 
signals.
    The FAA subsequently issued a notice of proposed rulemaking (NPRM) 
to amend 14 CFR part 39 by adding an AD that would apply to certain MHI 
RJ Aviation ULC Model CL-600-2B19 (Regional Jet Series 100 and 440), 
CL-600-2C10 (Regional Jet Series 700, 701, and 702), CL-600-2C11 
(Regional Jet Series 550), CL-600-2D15 (Regional Jet Series 705), CL-
600-2D24 (Regional Jet Series 900), and CL-600-2E25 (Regional Jet 
Series 1000) airplanes. The NPRM published in the Federal Register on 
September 9, 2024 (89 FR 73009). The NPRM was prompted by AD CF-2023-
62R1, dated November 21, 2023, issued by Transport Canada, which is the 
aviation authority for Canada (referred to after this as the MCAI). The 
MCAI states that, in addition to the effects of 5G C-Band broadband 
interference identified in FAA AD 2023-10-02, MHI RJ has determined 
that 5G C-Band broadband interference can result in certain failure 
messages and aural alerts being inhibited longer than intended. 
Specifically, this can result in the inhibition of hydraulic system #3 
and wing anti-ice overheat failure messages such that flightcrew are 
unable to perform appropriate airplane flight manual (AFM) procedures 
in the time needed to prevent loss of elevator control due to hydraulic 
system overheat and wing structural damage due to wing anti-ice system 
overheat. This condition, if not corrected, could result in delayed 
flightcrew response leading to loss of continued safe flight and 
landing.
    In the NPRM, the FAA proposed to require installing a new RF 
bandpass filter on the coaxial line between the radio altimeter and the 
receive antenna in the aft equipment compartment. When the airplane is 
modified as specified in this AD, the configuration with the RF 
bandpass filter installed has been determined to be ``radio altimeter 
tolerant.'' The FAA is issuing this AD because radio altimeter 
anomalies can result in the inhibition of certain failure messages such 
that the flightcrew are unable to perform appropriate airplane flight 
manual procedures in the time needed to prevent potential ignition 
hazard due to overheated hydraulic fluid circulating in the fuel tanks 
area, which may lead to loss of continued safe flight and landing, and/
or structural deformation of the wing leading edge which may reduce the 
safety margin (to stall).
    You may examine the MCAI in the AD docket at regulations.gov under 
Docket No. FAA-2024-1896.

Discussion of Final Airworthiness Directive

Comments

    The FAA received comments from Mesa Airlines, MHI RJ Aviation (MHI 
RJ), and an individual commenter. The following presents the comments 
received on the NPRM and the FAA's response to each comment.

Request To Refer To Revised Service Information

    MHI RJ and an individual commenter requested that the proposed AD 
be revised to refer to revised service bulletins. The individual 
commenter noted that MHI RJ Service Bulletin 670BA-34-054 is currently 
at Revision E. MHI RJ stated that the original issue and Revisions A, 
B, C, D, and E of MHI RJ Service Bulletin 670BA-34-054; and Revisions D 
and E of MHI RJ Service Bulletin 601R-34-152 should be listed as 
methods of compliance for the actions required by the proposed AD. MHI 
RJ also requested that all acceptable revisions of the referenced 
service information be added to paragraph (n) of the proposed AD.
    The FAA agrees to refer to the latest revisions of the service 
information. MHI RJ Service Bulletin 601R-34-152, Revision E, dated 
June 29, 2023, includes minor editorial changes (adding reference to an 
FAA AD and additional reference documents; and revising recommended 
compliance times, though the FAA notes that the compliance times in 
this AD take precedence over those in the service information). Those 
changes do not have an effect on the technical content and no 
additional work is necessary for operators that incorporated MHI RJ 
Service Bulletin 601R-34-152, Revision D, dated May 11, 2023. MHI RJ 
Service Bulletin 670BA-34-054, dated February 20, 2023; Revision A, 
dated February 28, 2023; Revision B, dated March 28, 2023; Revision C, 
dated June 29, 2023; Revision D, dated August 31, 2023; and Revision E, 
dated January 11, 2024; contain minor editorial revisions that do not 
have an effect on the technical content or require additional work for 
operators that incorporated earlier revisions. Therefore, the FAA has 
revised this AD to refer to MHI RJ Service Bulletin 670BA-34-054, 
Revision E, dated January 11, 2024; and MHI RJ Service Bulletin 601R-
34-152, Revision E, dated June 29, 2023.

[[Page 13280]]

    Regarding the request to cite all acceptable revisions of the 
service information in paragraph (n) of this AD, the FAA notes that 
paragraph (n) of this AD identifies only material that is to be 
incorporated by reference in the AD, and this AD requires and 
incorporates by reference only Revision E of the service bulletins, as 
specified in paragraphs (h), (i), and (j) of this AD.

Requests To Revise Credit for Previous Actions

    An individual commenter requested that the FAA revise paragraph (k) 
of the proposed AD to include credit for actions performed using the 
original issue or Revisions A, B, C, or D of MHI RJ Service Bulletin 
670BA-34-054. MHI RJ requested revising the conditional credit 
specified in the introductory text of paragraph (k) of the proposed AD 
to specify an additional document. MHI RJ noted that credit is 
conditional on operators installing the electrical idents for coax 
cables using Part G of MHI RJ Service Bulletin 601R-34-152, which is 
included only in Revisions D and E of that service information. MHI RJ 
also stated that some operators may have used, and should be granted 
credit for, Service Non-Incorporated Engineering Order (SNIEO) 
KCM601R53009-S01, which provides instructions for fabricating and 
installing electrical idents, and which is equivalent to Part G of 
Revision D and Revision E of MHI RJ Service Bulletin 601R-34-152.
    The FAA agrees with the commenters' requests. The FAA has revised 
paragraph (k) of this AD as follows:
     Revised paragraph (k)(1) of this AD to refer to MHI RJ 
Service Bulletin 601R-34-152, Revision E, dated June 29, 2023.
     Added paragraph (k)(2) of this AD to provide credit for 
actions done using certain revisions of MHI RJ Service Bulletin 601R-
34-152 provided that idents were installed using SNIEO KCM601R53009-S01 
or MHI RJ Service Bulletin 601R-34-152, Revision D, dated May 11, 2023.
     Added paragraph (k)(3) of this AD to provide credit for 
MHI RJ Service Bulletin 601R-34-152, Revision D, dated May 11, 2023.
     Added paragraph (k)(4) of this AD to provide credit for 
the original issue and Revisions A, B, C, or D of MHI RJ Service 
Bulletin 670BA-34-054.

Request To Clarify Applicability

    Mesa Airlines requested clarification of the affected Model CL-600-
2D24 (Regional Jet Series 900) airplanes in paragraph (c) of the 
proposed AD. The proposed AD identified manufacturer serial numbers 
(MSNs) 15001 through 15990, which, according to Mesa Airlines, is all 
Model CL-600-2D24 airplanes. The commenter noted, however, that the 
effectivity of MHI RJ Service Bulletin 670BA-34-054, dated February 20, 
2023, is limited to selected MSNs. That service bulletin was cited in 
paragraph (i) of the proposed AD as the appropriate source of service 
information for installing the RF bandpass filter for the specified 
airplanes including Model CL-600-2D24 airplanes.
    The FAA provides the following clarification. The effectivity in 
MHI RJ Service Bulletin 670BA-34-054, dated February 20, 2023, is 
limited to selected MSNs. According to MHI RJ, the initial issue of 
this service bulletin was intended for those operators interested in 
purchasing the modification, so the MSNs listed in that service 
bulletin were confirmed to be committed for purchase of the 
modification kits. Rather than revising the service bulletin 
effectivity each time a new MSN needed to be added, MHI RJ later 
decided to make the service bulletin applicable to all MSNs. Therefore, 
the effectivity in subsequent service bulletin revisions includes all 
MSNs. As stated previously, this AD has been changed to refer to MHI RJ 
Service Bulletin 670BA-34-054, Revision E, dated January 11, 2024, for 
the required actions for airplanes including Model CL-600-2D24 
airplanes.

Request To Clarify Unsafe Condition

    The Background section of the NPRM and paragraph (e) (``Unsafe 
Condition'') of the proposed AD stated that the FAA proposed the AD 
because radio altimeter anomalies can result in the inhibition of 
certain failure messages such that the flightcrew are unable to perform 
appropriate AFM procedures in the time needed to prevent ``loss of 
elevator control due to hydraulic system overheat and wing structural 
damage due to wing anti-ice system overheat,'' which could result in 
``delayed flightcrew response leading to loss of continued safe flight 
and landing.'' MHI RJ recommended that the FAA revise the proposed AD 
to state that the intent is rather to prevent ``potential ignition 
hazard due to overheated hydraulic fluid circulating in the fuel tanks 
area, which may lead to loss of continued safe flight and landing, and/
or structural deformation of the wing leading edge which may reduce the 
safety margin (to stall).''
    The FAA agrees with MHI RJ's proposed text, which better clarifies 
the radio altimeter anomalies that can result in the inhibition of 
certain failure messages. The Background section and paragraph (e) of 
this AD have been revised accordingly.

Request To Remove Statement Related to Unsafe Condition

    The Background section of the NPRM stated that MHI RJ determined 
that 5G C-Band broadband interference can result in certain failure 
messages and aural alerts being inhibited longer than intended. The 
Background then included the following statement:

    Specifically, this can result in the inhibition of hydraulic 
system #3 and wing anti-ice overheat failure messages such that 
flightcrew are unable to perform appropriate airplane flight manual 
(AFM) procedures in the time needed to prevent loss of elevator 
control due to hydraulic system overheat and wing structural damage 
due to wing anti-ice system overheat. This condition, if not 
corrected, could result in delayed flightcrew response leading to 
loss of continued safe flight and landing.

    MHI RJ recommended removing the quoted statement because that 
content is not included in Canadian AD CF-2023-46, and it is 
unnecessary and misleading.
    The FAA agrees to clarify. The FAA acknowledges that the specified 
text is not included in Transport Canada AD CF-2023-46. However, the 
FAA has determined that the added text provides additional details for 
a more comprehensive background of the unsafe condition identified in 
this final rule.

Request To Revise a Compliance Time

    MHI RJ recommended changing paragraph (j) of the proposed AD, which 
proposed to require installing an RF bandpass filter on Model CL-600-
2E25 airplanes ``before the next flight in the contiguous U.S. 
airspace'' after the effective date of the AD. MJI RJ recommended 
removing ``in the contiguous U.S. airspace'' because the proposed AD 
would apply to U.S.-registered airplanes operating in any airspace.
    The FAA disagrees with MHI RJ's request to change this compliance 
time language for Model CL-600-2E25 airplanes. The language has been 
retained in paragraph (j) of this AD to require compliance ``before the 
next flight in the contiguous U.S. airspace'' for Model CL-600-2E25 
airplanes because none of those affected airplanes are currently flying 
in the U.S, but the AD requirements will apply if an affected airplane 
is placed on the U.S. Registry and flown in the contiguous U.S. The FAA 
has not changed paragraph (j) of this AD as a result of this comment.

[[Page 13281]]

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, considered the 
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 this product. Except for minor editorial 
changes, and any other changes described previously, 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 MHI RJ Service Bulletins 601R-34-152, Revision E, 
dated June 29, 2023, and 670BA-34-054, Revision E, dated January 11, 
2024. This material specifies procedures for installing a new RF 
bandpass filter on the coaxial line between the radio altimeter and the 
receive antenna in the aft equipment compartment. These documents are 
distinct since they apply to different airplane models. 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 up to 873 airplanes of U.S. 
registry. However, many of these airplanes may already have a bandpass 
filter installed in compliance with AD 2023-10-02 and would not incur 
any additional costs to comply with this AD. The FAA estimates the 
following costs to comply with this AD:

                                                 Estimated Costs
----------------------------------------------------------------------------------------------------------------
                                                             Cost per
               Labor cost                   Parts cost        product             Cost on U.S. operators
----------------------------------------------------------------------------------------------------------------
58 work-hours x $85 per hour = $4,930...         $53,647         $58,577  Up to $51,137,721.
----------------------------------------------------------------------------------------------------------------

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

0
1. The authority citation for part 39 continues to read as follows:

    Authority: 49 U.S.C. 106(f), 40113, 44701.


Sec.  39.13  [Amended]

0
2. The FAA amends Sec.  39.13 by adding the following new airworthiness 
directive:

2025-04-08 MHI RJ Aviation ULC (Type Certificate Previously Held by 
Bombardier Inc.): Amendment 39-22966; Docket No. FAA-2024-1896; 
Project Identifier MCAI-2023-00978-T.

(a) Effective Date

    This airworthiness directive (AD) is effective April 25, 2025.

(b) Affected ADs

    None.

(c) Applicability

    This AD applies to the MHI RJ Aviation ULC (Type Certificate 
previously held by Bombardier Inc.) airplanes identified in 
paragraphs (c)(1) through (6) of this AD, certificated in any 
category, that are equipped with a radio altimeter and not 
determined to be a radio altimeter tolerant airplane as defined in 
paragraph (g) of this AD.
    (1) Model CL-600-2B19 (Regional Jet Series 100 and 440) 
airplanes, serial number (S/N) 7002 through 8113.
    (2) Model CL-600-2C10 (Regional Jet Series 700, 701, and 702) 
airplanes, S/N 10002 through 10999.
    (3) Model CL-600-2C11 (Regional Jet Series 550) airplanes, S/N 
10002 through 10999.
    (4) Model CL-600-2D15 (Regional Jet Series 705) airplanes, S/N 
15001 through 15990.
    (5) Model CL-600-2D24 (Regional Jet Series 900) airplanes, S/N 
15001 through 15990.
    (6) Model CL-600-2E25 (Regional Jet Series 1000) airplanes, S/N 
19013 through 19990.

(d) Subject

    Air Transport Association (ATA) of America Code 34, Navigation.

(e) Unsafe Condition

    This AD was prompted by the determination that radio altimeters 
cannot be relied upon to perform their intended function if they 
experience interference from wireless broadband operations in the 
3.7-3.98 GHz frequency band (5G C-Band). The FAA is issuing this AD 
because radio altimeter anomalies can result in the inhibition of 
certain failure messages such that the flightcrew are unable to 
perform appropriate airplane flight manual procedures in the time 
needed to prevent potential ignition hazard due to overheated 
hydraulic fluid circulating in the fuel tanks area, which may lead 
to loss of continued safe flight and landing, and/or structural 
deformation of the wing leading edge which may reduce the safety 
margin (to stall).

[[Page 13282]]

(f) Compliance

    Comply with this AD within the compliance times specified, 
unless already done.

(g) Definitions

    For purposes of this AD, a ``radio altimeter tolerant airplane'' 
is one for which the radio altimeter, as installed, demonstrates the 
tolerances specified in paragraphs (g)(1) and (2) of this AD, using 
a method approved by the FAA. No actions are required by this AD for 
radio altimeter tolerant airplanes.
    (1) Tolerance to radio altimeter interference, for the 
fundamental emissions (3.7-3.98 GHz), at or above the power spectral 
density (PSD) curve threshold specified in figure 1 to paragraph 
(g)(1) of this AD.

Figure 1 to Paragraph (g)(1)--Fundamental Effective Isotropic PSD at 
Outside Interface of Airplane Antenna

BILLING CODE 4910-13-P
[GRAPHIC] [TIFF OMITTED] TR21MR25.000

    (2) Tolerance to radio altimeter interference, for the spurious 
emissions (4.2-4.4 GHz), at or above the PSD curve threshold 
specified in figure 2 to paragraph (g)(2) of this AD.

Figure 2 to Paragraph (g)(2)--Spurious Effective Isotropic PSD at 
Outside Interface of Airplane Antenna

[[Page 13283]]

[GRAPHIC] [TIFF OMITTED] TR21MR25.001

BILLING CODE 4910-13-C

(h) Filter Installation: Model CL-600-2B19

    For Model CL-600-2B19 airplanes: Within 2,300 flight hours or 12 
months after the effective date of this AD, whichever occurs first, 
install a radio frequency (RF) bandpass filter on each radio 
altimeter in accordance with the applicable parts of the 
Accomplishment Instructions in MHI RJ Service Bulletin 601R-34-152, 
Revision E, dated June 29, 2023. Alternatively, airplanes with a 
dual radio altimeter configuration may comply with this paragraph by 
installing an RF bandpass filter on one radio altimeter and 
deactivating the second radio altimeter in accordance with the 
applicable parts of the Accomplishment Instructions in MHI RJ 
Service Bulletin 601R-34-152, Revision E, dated June 29, 2023.

(i) Filter Installation: Model CL-600-2C10, CL-600-2C11, CL-600-2D15, 
and CL-600-2D24

    For Model CL-600-2C10, CL-600-2C11, CL-600-2D15, and CL-600-2D24 
airplanes: Within 2,100 flight hours or 12 months after the 
effective date of this AD, whichever occurs first, install an RF 
bandpass filter on each radio altimeter in accordance with the 
applicable parts of the Accomplishment Instructions in MHI RJ 
Service Bulletin 670BA-34-054, Revision E, dated January 11, 2024. 
Alternatively, airplanes with a dual radio altimeter configuration 
may comply with this paragraph by installing an RF bandpass filter 
on one radio altimeter and deactivating the second radio altimeter 
in accordance with the applicable parts of the Accomplishment 
Instructions in MHI RJ Service Bulletin 670BA-34-054, Revision E, 
dated January 11, 2024.

(j) Filter Installation: Model CL-600-2E25

    For Model CL-600-2E25 airplanes: Before the next flight in the 
contiguous U.S. airspace after the effective date of this AD, 
install an RF bandpass filter on each radio altimeter in

[[Page 13284]]

accordance with the applicable parts of the Accomplishment 
Instructions in MHI RJ Service Bulletin 670BA-34-054, Revision E, 
dated January 11, 2024.

(k) Credit for Previous Actions

    (1) For Model CL-600-2B19 airplanes: This paragraph provides 
credit for the actions required by paragraph (h) of this AD, if 
those actions were performed before the effective date of this AD 
using the material in paragraphs (k)(1)(i) through (iv) of this AD, 
provided the electrical idents for coax cables are installed using 
Part G of the Accomplishment Instructions in MHI RJ Service Bulletin 
601R-34-152, Revision E, dated June 29, 2023, within the compliance 
time specified in paragraph (h) of this AD.
    (i) MHI RJ Service Bulletin 601R-34-152, dated February 14, 
2023.
    (ii) MHI RJ Service Bulletin 601R-34-152, Revision A, dated 
February 28, 2023.
    (iii) MHI RJ Service Bulletin 601R-34-152, Revision B, dated 
March 28, 2023.
    (iv) MHI RJ Service Bulletin 601R-34-152, Revision C, dated 
April 20, 2023.
    (2) For Model CL-600-2B19 airplanes: This paragraph provides 
credit for the actions required by paragraph (h) of this AD, if 
those actions were performed before the effective date of this AD 
using the material in paragraphs (k)(2)(i) through (iv) of this AD, 
provided the electrical idents for coax cables were installed using 
Part G of the Accomplishment Instructions in MHI RJ Service Bulletin 
601R-34-152, Revision D, dated May 11, 2023, or MHI RJ Service Non-
Incorporated Engineering Order (SNIEO) KCM601R53009-S01, dated May 
2, 2023, prior to the effective date of this AD.
    (i) MHI RJ Service Bulletin 601R-34-152, dated February 14, 
2023.
    (ii) MHI RJ Service Bulletin 601R-34-152, Revision A, dated 
February 28, 2023.
    (iii) MHI RJ Service Bulletin 601R-34-152, Revision B, dated 
March 28, 2023.
    (iv) MHI RJ Service Bulletin 601R-34-152, Revision C, dated 
April 20, 2023.
    (3) For Model CL-600-2B19 airplanes: This paragraph provides 
credit for the actions required by paragraph (h) of this AD, if 
those actions were performed before the effective date of this AD 
using MHI RJ Service Bulletin 601R-34-152, Revision D, dated May 11, 
2023.
    (4) For Model CL-600-2C10, CL-600-2C11, CL-600-2D15, CL-600-
2D24, and CL-600-2E25 airplanes: This paragraph provides credit for 
the actions required by paragraphs (i) and (j) of this AD, as 
applicable, if those actions were performed before the effective 
date of this AD using the material in paragraphs (k)(4)(i) through 
(v) of this AD.
    (i) MHI RJ Service Bulletin 670BA-34-054, dated February 20, 
2023.
    (ii) MHI RJ Service Bulletin 670BA-34-054, Revision A, dated 
February 28, 2023.
    (iii) MHI RJ Service Bulletin 670BA-34-054, Revision B, dated 
March 28, 2023.
    (iv) MHI RJ Service Bulletin 670BA-34-054, Revision C, dated 
June 29, 2023.
    (v) MHI RJ Service Bulletin 670BA-34-054, Revision D, dated 
August 31, 2023.

(l) 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 (m)(1) of this AD. Information may be emailed to 
[email protected]. 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 Transport Canada; or MHI RJ Aviation 
ULC's Transport Canada Design Approval Organization (DAO). If 
approved by the DAO, the approval must include the DAO-authorized 
signature.

(m) Additional Information

    (1) For more information about this AD, contact Steven 
Dzierzynski, Aviation Safety Engineer, FAA, 1600 Stewart Avenue, 
Suite 410, Westbury, NY 11590; telephone 516-228-7300; email [email protected].
    (2) Material identified in this AD that is not incorporated by 
reference is available at the address specified in paragraph (n)(3) 
of this AD.

(n) Material Incorporated by Reference

    (1) The Director of the Federal Register approved the 
incorporation by reference 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) MHI RJ Service Bulletin 601R-34-152, Revision E, dated June 
29, 2023.
    (ii) MHI RJ Service Bulletin 670BA-34-054, Revision E, dated 
January 11, 2024.
    (3) For MHI RJ material identified in this AD, contact MHI RJ 
Aviation Group, Customer Response Center, 3655 Ave. des Grandes-
Tourelles, Suite 110, Boisbriand, Qu[eacute]bec J7H 0E2 Canada; 
North America toll-free telephone 833-990-7272 or direct-dial 
telephone 450-990-7272; fax 514-855-8501; email mhirj.com">thd.crj@mhirj.com; 
website mhirj.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/ibr-locations, or email [email protected].

    Issued on February 18, 2025.
Victor Wicklund,
Deputy Director, Compliance & Airworthiness Division, Aircraft 
Certification Service.
[FR Doc. 2025-04720 Filed 3-20-25; 8:45 am]
BILLING CODE 4910-13-P
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