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Final Rule

Airworthiness Directives; Bell Textron Canada Limited Helicopters

Final rule; request for comments.

📖 Research Context From Federal Register API

Summary:

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.

Key Dates
Citation: 90 FR 43544
This AD is effective September 25, 2025.
Comments closed: October 27, 2025
Public Participation
1 comment 1 supporting doc
View on Regulations.gov →
Topics:
Air transportation Aircraft Aviation safety Incorporation by reference Safety

In Plain English

What is this Federal Register notice?

This is a final rule published in the Federal Register by Transportation Department, Federal Aviation Administration. Final rules have completed the public comment process and establish legally binding requirements.

Is this rule final?

Yes. This rule has been finalized. It has completed the notice-and-comment process required under the Administrative Procedure Act.

Who does this apply to?

Final rule; request for comments.

When does it take effect?

This document has been effective since September 25, 2025.

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Document Details

Document Number2025-17384
FR Citation90 FR 43544
TypeFinal Rule
PublishedSep 10, 2025
Effective DateSep 25, 2025
RIN2120-AA64
Docket IDDocket No. FAA-2025-2276
Pages43544–43546 (3 pages)
Text FetchedYes

Agencies & CFR References

CFR References:

Linked CFR Parts

PartNameAgency
14 CFR 39 Airworthiness Directives... Federal Aviation Administration

Paired Documents

TypeProposedFinalMethodConf
No paired documents

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Full Document Text (2,737 words · ~14 min read)

Text Preserved
<RULE> DEPARTMENT OF TRANSPORTATION <SUBAGY>Federal Aviation Administration</SUBAGY> <CFR>14 CFR Part 39</CFR> <DEPDOC>[Docket No. FAA-2025-2276; Project Identifier MCAI-2025-00699-R; Amendment 39-23137; AD 2025-18-10]</DEPDOC> <RIN>RIN 2120-AA64</RIN> <SUBJECT>Airworthiness Directives; Bell Textron Canada Limited Helicopters</SUBJECT> <HD SOURCE="HED">AGENCY:</HD> Federal Aviation Administration (FAA), DOT. <HD SOURCE="HED">ACTION:</HD> Final rule; request for comments. <SUM> <HD SOURCE="HED">SUMMARY:</HD> 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. </SUM> <EFFDATE> <HD SOURCE="HED">DATES:</HD> This AD is effective September 25, 2025. The Director of the Federal Register approved the incorporation by reference of a certain publication listed in this AD as of September 25, 2025. The FAA must receive comments on this AD by October 27, 2025. </EFFDATE> <HD SOURCE="HED">ADDRESSES:</HD> You may send comments, using the procedures found in 14 CFR 11.43 and 11.45, by any of the following methods: • <E T="03">Federal eRulemaking Portal:</E> Go to <E T="03">regulations.gov</E> . Follow the instructions for submitting comments. • <E T="03">Fax:</E> (202) 493-2251. • <E T="03">Mail:</E> U.S. Department of Transportation, Docket Operations, M-30, West Building Ground Floor, Room W12-140, 1200 New Jersey Avenue SE, Washington, DC 20590. • <E T="03">Hand Delivery:</E> Deliver to Mail address above between 9 a.m. and 5 p.m., Monday through Friday, except Federal holidays. <E T="03">AD Docket:</E> You may examine the AD docket at <E T="03">regulations.gov</E> 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. <E T="03">Material Incorporated by Reference:</E> • 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: <E T="03">TC.AirworthinessDirectives-Consignesdenavigabilite.TC@tc.gc.ca.</E> You may find the Transport Canada material on the Transport Canada website at <E T="03">tc.canada.ca/en/aviation.</E> • 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 <E T="03">regulations.gov</E> under Docket No. FAA-2025-2276. <FURINF> <HD SOURCE="HED">FOR FURTHER INFORMATION CONTACT:</HD> Steven Warwick, Aviation Safety Engineer, FAA, 1600 Stewart Avenue, Suite 410, Westbury, NY 11590; phone: (817) 222-5225; email: <E T="03">steven.r.warwick@faa.gov.</E> </FURINF> <SUPLINF> <HD SOURCE="HED">SUPPLEMENTARY INFORMATION:</HD> <HD SOURCE="HD1">Comments Invited</HD> 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 <E T="02">ADDRESSES</E> 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 <E T="03">regulations.gov,</E> including any personal information you provide. The agency will also post a report summarizing each substantive verbal contact received about this final rule. <HD SOURCE="HD1">Confidential Business Information</HD> 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. <HD SOURCE="HD1">Background</HD> 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 <E T="03">regulations.gov</E> under Docket No. FAA-2025-2276. <HD SOURCE="HD1">Material Incorporated by Reference Under 1 CFR Part 51</HD> 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 <E T="02">ADDRESSES</E> section. <HD SOURCE="HD1">FAA's Determination</HD> 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. <HD SOURCE="HD1">AD Requirements</HD> 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. <HD SOURCE="HD1">Explanation of Required Compliance Information</HD> 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 <E T="03">regulations.gov</E> under Docket No. FAA-2025-2276 after this AD is published. <HD SOURCE="HD1">Justification for Immediate Adoption and Determination of the Effective Date</HD> Section 553(b) of the Administrative Procedure Act (APA) (5 U.S.C. 551 <E T="03">et seq.</E> ) 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 cool ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━ Preview showing 10k of 19k characters. Full document text is stored and available for version comparison. ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━
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