AD 2025-18-10 ACTIVE

The FAA is adopting a new airworthiness directive (AD) for certain Bell Textron Canada Limited Model 505 helicopters. This AD was prompted by a report of a crack on the mounting bracket on the oil cooler fan assembly housing. This AD requires a one-time visual inspection for cracks on the mounting bracket on the oil cooler fan assembly housing and modification of the mounting bracket. The FAA is issuing this AD to address the unsafe condition on these products.

Final rule; request for comments.

1. The authority citation for part 39 continues to read as follows: Authority: 49 U.S.C. 106(g), 40113, 44701. 2. The FAA amends § 39.13 by adding the following new airworthiness directive: 2025-18-10 Bell Textron Canada Limited: Amendment 39-23137; Docket No. FAA-2025-2276; Project Identifier MCAI-2025-00699-R. (a) Effective Date This airworthiness directive (AD) is effective September 25, 2025. (b) Affected ADs None. (c) Applicability This AD applies to Bell Textron Canada Limited Model 505 helicopters, serial numbers 65011 through 65020 inclusive and 65022 through 65027 inclusive, certificated in any category. (d) Subject Joint Aircraft System Component (JASC) Code 7311, Engine Fuel/Oil Cooler. (e) Unsafe Condition This AD was prompted by a report of a cracked mounting bracket on the oil cooler fan assembly housing. The FAA is issuing this AD to prevent cracking on the mounting bracket of the oil cooler fan assembly housing. The unsafe condition, if not addressed, could lead to failure of the drive shaft and loss of the tail rotor drive with consequent loss of control of the helicopter. (f) Compliance Comply with this AD within the compliance times specified, unless already done. (g) Requirements Except as specified in paragraph (h) of this AD: Comply with all required actions and compliance times specified in, and in accordance with, Transport Canada AD CF-2025-23, dated April 23, 2025 (Transport Canada AD CF-2025-23). (h) Exceptions to Transport Canada AD CF-2025-23 (1) Where Transport Canada AD CF-2025-23 refers to its effective date, this AD requires using the effective date of this AD. (2) Where Transport Canada AD CF-2025-23 requires compliance in terms of air time, this AD requires using hours time-in-service. (3) Where Transport Canada AD CF-2025-23 specifies "Within 25 hours air time or 30 days from the effective date of this AD", this AD requires replacing that text with "Within 25 hours time-in-service or 30 days from the effective date of this AD, whichever occurs first". (4) Where paragraph 1. of Transport Canada AD CF-2025-23 specifies "conduct a visual inspection of the right bracket of the oil cooler blower housing", this AD requires replacing that text with "conduct a visual inspection and, if applicable, a gap measurement of the right bracket of the oil cooler blower housing". (i) Alternative Methods of Compliance (AMOCs) (1) 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 local Flight Standards District Office, as appropriate. If sending information directly to the manager of the International Validation Branch, send it to the attention of the person identified in paragraph (j) of this AD and email to: AMOC@faa.gov. (2) Before using any approved AMOC, notify your appropriate principal inspector, or lacking a principal inspector, the manager of the local Flight Standards District Office/certificate holding district office. (j) Additional Information For more information about this AD, contact Steven Warwick, Aviation Safety Engineer, FAA, 1600 Stewart Avenue, Suite 410, Westbury, NY 11590; phone: (817) 222-5225; email: steven.r.warwick@faa.gov. (k) 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 the AD specifies otherwise. (i) Transport Canada AD CF-2025-23, dated April 23, 2025. (ii) [Reserved] (3) For Transport Canada material identified in this AD, contact Transport Canada National Aircraft Certification, 159 Cleopatra Drive, Nepean, Ontario K1A 0N5, Canada; phone: (888) 663-3639; email: TC.AirworthinessDirectives-Consignesdenavigabilite.TC@tc.gc.ca. You may find this material on the Transport Canada website at tc.canada.ca/en/aviation. (4) You may view this material at the FAA, Office of the Regional Counsel, Southwest Region, 10101 Hillwood Parkway, Room 6N-321, Fort Worth, TX 76177. For information on the availability of this material at the FAA, call (817) 222-5110. (5) You may view this material at the National Archives and Records Administration (NARA). For information on the availability of this material at NARA, visit www.archives.gov/federal-register/cfr/ibr-locations or email fr.inspection@nara.gov . Issued on September 5, 2025. Steven W. Thompson, Acting Deputy Director, Compliance & Airworthiness Division, Aircraft Certification Service. [FR Doc. 2025-17384 Filed 9-8-25; 11:15 am]BILLING CODE 4910-13-P

Comments Invited The FAA invites you to send any written data, views, or arguments about this final rule. Send your comments using a method listed under the ADDRESSES section. Include "Docket No. FAA-2025-2276; Project Identifier MCAI-2025-00699-R" at the beginning of your comments. The most helpful comments reference a specific portion of the final rule, explain the reason for any recommended change, and include supporting data. The FAA will consider all comments received by the closing date and may amend this final rule because of those comments. Except for Confidential Business Information (CBI) as described in the following paragraph, and other information as described in 14 CFR 11.35, the FAA will post all comments received, without change, to regulations.gov, including any personal information you provide. The agency will also post a report summarizing each substantive verbal contact received about this final rule. Confidential Business Information CBI is commercial or financial information that is both customarily and actually treated as private by its owner. Under the Freedom of Information Act (FOIA) (5 U.S.C. 552), CBI is exempt from public disclosure. If your comments responsive to this AD contain commercial or financial information that is customarily treated as private, that you actually treat as private, and that is relevant or responsive to this AD, it is important that you clearly designate the submitted comments as CBI. Please mark each page of your submission containing CBI as "PROPIN." The FAA will treat such marked submissions as confidential under the FOIA, and they will not be placed in the public docket of this AD. Submissions containing CBI should be sent to Steven Warwick, Aviation Safety Engineer, FAA, 1600 Stewart Avenue, Suite 410, Westbury, NY 11590. Any commentary that the FAA receives which is not specifically designated as CBI will be placed in the public docket for this rulemaking. Background Transport Canada, which is the aviation authority for Canada, has issued Transport Canada AD CF-2025-23, dated April 23, 2025 (Transport Canada AD CF-2025-23) (also referred to as "the MCAI"), to correct an unsafe condition on Bell Textron Canada Limited Model 505 helicopters, serial numbers 65011 through 65020 and 65022 through 65027. The MCAI states that an occurrence of a cracked mounting bracket on the oil cooler fan assembly housing was reported. During the subsequent investigation, it was determined that the initial design of a 'Z' shaped bracket that was welded to the oil cooler fan assembly housing and then bolted to a bracket on the truss was susceptible to cracking. As a result, the manufacturer improved the design of the mounting bracket to incorporate a slotted bracket bolted to both the oil cooler fan assembly housing and the truss. The MCAI requires a one-time visual inspection for cracks and modification of the right bracket of the oil cooler fan assembly housing. The unsafe condition, if not addressed, could lead to failure of the drive shaft, loss of the tail rotor drive, and consequent loss of control of the helicopter. You may examine the MCAI in the AD docket at regulations.gov under Docket No. FAA-2025-2276. Material Incorporated by Reference Under 1 CFR Part 51 The FAA reviewed Transport Canada AD CF-2025-23, which specifies procedures for a one-time visual inspection for cracks and modification of the right bracket of the oil cooler fan assembly housing. 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. FAA's Determination These products have been approved by the aviation authority of another country and are 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 is issuing this AD after determining that the unsafe condition described previously is likely to exist or develop on other products of the same type design. AD Requirements This AD requires accomplishing the actions specified in Transport Canada AD CF-2025-23, described previously, except for any differences identified as exceptions in the regulatory text of this AD. Explanation of Required Compliance Information In the FAA's ongoing efforts to improve the efficiency of the AD process, the FAA developed a process to use some civil aviation authority (CAA) ADs as the primary source of information for compliance with requirements for corresponding FAA ADs. The FAA has been coordinating this process with manufacturers and CAAs. As a result, Transport Canada AD CF-2025-23 is incorporated by reference in this AD. This AD requires compliance with Transport Canada AD CF-2025-23 in its entirety through that incorporation, except for any differences identified as exceptions in the regulatory text of this AD. Material required by Transport Canada AD CF-2025-23 for compliance will be available at regulations.gov under Docket No. FAA-2025-2276 after this AD is published. Justification for Immediate Adoption and Determination of the Effective Date Section 553(b) of the Administrative Procedure Act (APA) (5 U.S.C. 551 et seq. ) authorizes agencies to dispense with notice and comment procedures for rules when the agency, for "good cause," finds that those procedures are "impracticable, unnecessary, or contrary to the public interest." Under this section, an agency, upon finding good cause, may issue a final rule without providing notice and seeking comment prior to issuance. Further, section 553(d) of the APA authorizes agencies to make rules effective in less than thirty days, upon a finding of good cause. An unsafe condition exists that requires the immediate adoption of this AD without providing an opportunity for public comments prior to adoption. The FAA has found that the risk to the flying public justifies forgoing notice and comment prior to adoption of this rule because the failure of the mounting support of the oil cooler fan assembly housing could lead to failure of the drive shaft, loss of the tail rotor drive, and consequent loss of control of the helicopter. For this reason, the initial actions required by this AD must be accomplished within 25 hours time-in-service or 30 days, whichever occurs first, which is shorter than the time necessary for the public to comment and for publication of the final rule. Accordingly, notice and opportunity for prior public comment are impracticable and contrary to the public interest pursuant to 5 U.S.C. 553(b). In addition, the FAA finds that good cause exists pursuant to 5 U.S.C. 553(d) for making this amendment effective in less than 30 days, for the same reasons the FAA found good cause to forgo notice and comment. Regulatory Flexibility Act The requirements of the Regulatory Flexibility Act (RFA) do not apply when an agency finds good cause pursuant to 5 U.S.C. 553 to adopt a rule without prior notice and comment. Because the FAA has determined that it has good cause to adopt this rule without prior notice and comment, RFA analysis is not required. Costs of Compliance The FAA estimates that this AD affects six helicopters of U.S. registry. The FAA estimates the following costs to comply with this AD: Estimated Costs Action Labor cost Parts cost Cost per product Cost on U.S. operators Inspect mounting bracket 1.5 work-hours × $85 per hour = $128 $0 $128 $768 Modify right mounting bracket 2.5 work-hours × $85 per hour = $213 0 213 1,278 The FAA has included all known costs in its cost estimate. According to the manufacturer, however, some of the costs of this AD may be covered under warranty, thereby reducing the cost impact on affected operators. Authority for This Rulemaking Title 49 of the United States Code specifies the FAA's authority to issue rules on aviation safety. Subtitle I, section 106, describes the authority of 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, and (2) Will not affect intrastate aviation in Alaska. 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: 2025-18-10 Bell Textron Canada Limited: Amendment 39-23137; Docket No. FAA-2025-2276; Project Identifier MCAI-2025-00699-R. (a) Effective Date This airworthiness directive (AD) is effective September 25, 2025. (b) Affected ADs None. (c) Applicability This AD applies to Bell Textron Canada Limited Model 505 helicopters, serial numbers 65011 through 65020 inclusive and 65022 through 65027 inclusive, certificated in any category. (d) Subject Joint Aircraft System Component (JASC) Code 7311, Engine Fuel/Oil Cooler. (e) Unsafe Condition This AD was prompted by a report of a cracked mounting bracket on the oil cooler fan assembly housing. The FAA is issuing this AD to prevent cracking on the mounting bracket of the oil cooler fan assembly housing. The unsafe condition, if not addressed, could lead to failure of the drive shaft and loss of the tail rotor drive with consequent loss of control of the helicopter. (f) Compliance Comply with this AD within the compliance times specified, unless already done. (g) Requirements Except as specified in paragraph (h) of this AD: Comply with all required actions and compliance times specified in, and in accordance with, Transport Canada AD CF-2025-23, dated April 23, 2025 (Transport Canada AD CF-2025-23). (h) Exceptions to Transport Canada AD CF-2025-23 (1) Where Transport Canada AD CF-2025-23 refers to its effective date, this AD requires using the effective date of this AD. (2) Where Transport Canada AD CF-2025-23 requires compliance in terms of air time, this AD requires using hours time-in-service. (3) Where Transport Canada AD CF-2025-23 specifies "Within 25 hours air time or 30 days from the effective date of this AD", this AD requires replacing that text with "Within 25 hours time-in-service or 30 days from the effective date of this AD, whichever occurs first". (4) Where paragraph 1. of Transport Canada AD CF-2025-23 specifies "conduct a visual inspection of the right bracket of the oil cooler blower housing", this AD requires replacing that text with "conduct a visual inspection and, if applicable, a gap measurement of the right bracket of the oil cooler blower housing". (i) Alternative Methods of Compliance (AMOCs) (1) 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 local Flight Standards District Office, as appropriate. If sending information directly to the manager of the International Validation Branch, send it to the attention of the person identified in paragraph (j) of this AD and email to: AMOC@faa.gov. (2) Before using any approved AMOC, notify your appropriate principal inspector, or lacking a principal inspector, the manager of the local Flight Standards District Office/certificate holding district office. (j) Additional Information For more information about this AD, contact Steven Warwick, Aviation Safety Engineer, FAA, 1600 Stewart Avenue, Suite 410, Westbury, NY 11590; phone: (817) 222-5225; email: steven.r.warwick@faa.gov. (k) 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 the AD specifies otherwise. (i) Transport Canada AD CF-2025-23, dated April 23, 2025. (ii) [Reserved] (3) For Transport Canada material identified in this AD, contact Transport Canada National Aircraft Certification, 159 Cleopatra Drive, Nepean, Ontario K1A 0N5, Canada; phone: (888) 663-3639; email: TC.AirworthinessDirectives-Consignesdenavigabilite.TC@tc.gc.ca. You may find this material on the Transport Canada website at tc.canada.ca/en/aviation. (4) You may view this material at the FAA, Office of the Regional Counsel, Southwest Region, 10101 Hillwood Parkway, Room 6N-321, Fort Worth, TX 76177. For information on the availability of this material at the FAA, call (817) 222-5110. (5) You may view this material at the National Archives and Records Administration (NARA). For information on the availability of this material at NARA, visit www.archives.gov/federal-register/cfr/ibr-locations or email fr.inspection@nara.gov . Issued on September 5, 2025. Steven W. Thompson, Acting Deputy Director, Compliance & Airworthiness Division, Aircraft Certification Service.

You may send comments, using the procedures found in 14 CFR 11.43 and 11.45, by any of the following methods: - Federal eRulemaking Portal: Go to regulations.gov . Follow the instructions for submitting comments. - Fax: (202) 493-2251. - Mail: U.S. Department of Transportation, Docket Operations, M-30, West Building Ground Floor, Room W12-140, 1200 New Jersey Avenue SE, Washington, DC 20590. - Hand Delivery: Deliver to Mail address above between 9 a.m. and 5 p.m., Monday through Friday, except Federal holidays. AD Docket: You may examine the AD docket at regulations.gov under Docket No. FAA-2025-2276; 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 street address for Docket Operations is listed above. Material Incorporated by Reference: - For Transport Canada material identified in this AD, contact Transport Canada, Transport Canada National Aircraft Certification, 159 Cleopatra Drive, Nepean, Ontario, K1A 0N5, Canada; phone: (888) 663-3639; email: TC.AirworthinessDirectives-Consignesdenavigabilite.TC@tc.gc.ca. You may find the Transport Canada material on the Transport Canada website at tc.canada.ca/en/aviation. - You may view this material at the FAA, Office of the Regional Counsel, Southwest Region, 10101 Hillwood Parkway, Room 6N-321, Fort Worth, TX 76177. For information on the availability of this material at the FAA, call (817) 222-5110. It is also available at regulations.gov under Docket No. FAA-2025-2276.

Steven Warwick, Aviation Safety Engineer, FAA, 1600 Stewart Avenue, Suite 410, Westbury, NY 11590; phone: (817) 222-5225; email: steven.r.warwick@faa.gov.