DEPARTMENT OF TRANSPORTATION
<SUBAGY>Federal Aviation Administration</SUBAGY>
<CFR>14 CFR Part 39</CFR>
<DEPDOC>[Docket No. FAA-2025-5030; Project Identifier MCAI-2025-00322-R]</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>
Notice of proposed rulemaking (NPRM).
<SUM>
<HD SOURCE="HED">SUMMARY:</HD>
The FAA proposes to adopt a new airworthiness directive (AD) for certain Bell Textron Canada Limited Model 429 helicopters. This proposed AD was prompted by reports of incorrectly installed lockwire on the stability and control augmentation system (SCAS) actuator jam nut. This proposed AD would require inspecting the installation of the lockwire on the SCAS actuator jam nut and, if the lockwire is incorrectly installed, removing the lockwire and installing a new lockwire correctly. This proposed AD would also prohibit the installation of an affected SCAS actuator assembly unless certain requirements are met. The FAA is proposing this AD to address the unsafe condition on these products.
</SUM>
<EFFDATE>
<HD SOURCE="HED">DATES:</HD>
The FAA must receive comments on this NPRM by January 8, 2026.
</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-2025-5030; 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 NPRM, 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>
website:
<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.
<FURINF>
<HD SOURCE="HED">FOR FURTHER INFORMATION CONTACT:</HD>
Kim-Anh Tran, Aviation Safety Engineer, FAA, 1600 Stewart Avenue, Suite 410, Westbury, NY 11590; phone: (316) 946-4190; email:
<E T="03">kim-anh.t.tran@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 relevant data, views, or arguments about this proposal. Send your comments using a method listed under the
<E T="02">ADDRESSES</E>
section. Include “Docket No. FAA-2025-5030; Project Identifier MCAI-2025-00322-R” at the beginning of your comments. The most helpful comments reference a specific portion of the proposal, 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 proposal 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 NPRM.
<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 NPRM 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 NPRM, 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 NPRM. Submissions containing CBI should be sent to Kim-Anh Tran, 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-2025-16, dated March 17, 2025 (Transport Canada AD CF-2025-16) (also referred to as the MCAI), to correct an unsafe condition on Bell Textron Canada Limited Model 429 helicopters, serial numbers 57001 and subsequent, with SCAS actuator part numbers (P/N) 429-001-065-107, 429-001-065-109, or 429-001-065-111 installed. The MCAI states that there have been several reports of incorrectly installed lockwire on the SCAS actuator jam nut. The MCAI further states that the incorrect installation of the lockwire could allow the actuator jam nut to loosen. This condition, if not addressed, could lead to the SCAS actuator rotating on the axis of the tube, interfering with the adjacent structure and limiting or completely jamming control movement, resulting in partial or complete 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-2025-5030.
<HD SOURCE="HD1">Material Incorporated by Reference Under 1 CFR Part 51</HD>
The FAA reviewed Transport Canada AD CF-2025-16, dated March 17, 2025, which specifies procedures for a one-time inspection of the lockwire installation of the jam nuts of the cyclic longitudinal, cyclic lateral, and directional SCAS actuators and, if the lockwire is improperly installed, removal of the lockwire and installation of a new lockwire in the correct direction. Transport Canada AD CF-2025-16 also prohibits the installation of an affected SCAS actuator assembly unless certain requirements are met. 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 civil aviation authority (CAA) 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, that authority has notified the FAA of the unsafe condition described in the MCAI and material referenced above. The FAA is issuing this NPRM 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">Proposed AD Requirements in This NPRM</HD>
This proposed AD would require accomplishing the actions specified in the material already described.
<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 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, the FAA proposes to incorporate Transport Canada AD CF-2025-16 by reference in the FAA final rule. This proposed AD would, therefore, require compliance with Transport Canada AD CF-2025-16 in its entirety through that incorporation, except for any differences identified as exceptions in the regulatory text of this proposed AD. Material required by Transport Canada AD CF-2025-16 for compliance will be available at
<E T="03">regulations.gov</E>
under Docket No. FAA-2025-5030 after the FAA final rule is published.
<HD SOURCE="HD1">Costs of Compliance</HD>
The FAA estimates that this AD, if adopted as proposed, would affect 101 helicopters of U.S. registry.
The FAA estimates the following costs to comply with this proposed AD:
<GPOTABLE COLS="5" OPTS="L2,i1" CDEF="s25,r50,10,10,12">
<TTITLE>Estimated Costs</TTITLE>
<CHED H="1">Action</CHED>
<CHED H="1">Labor cost</CHED>
<CHED H="1">Parts cost</CHED>
Cost on U.S.
operators
</CHED>
<ROW>
<ENT I="01">Inspect lockwire</ENT>
<ENT>1.5 work-hour × $85 per hour = $128</ENT>
<ENT>$0</ENT>
<ENT>$128</ENT>
<ENT>$12,928</ENT>
</ROW>
</GPOTABLE>
The FAA estimates the following costs to do any necessary repairs that would be required based on the results of the proposed inspection. The agency has no way of determining the number of helicopters that might need this repair:
<GPOTABLE COLS="4" OPTS="L2,nj,i1" CDEF="s25,r50,10,16">
<TTITLE>On-Condition Costs</TTITLE>
<CHED H="1">Action</CHED>
<CHED H="1">Labor cost</CHED>
<CHED H="1">Parts cost</CHED>
<CHED H="1">Cost per product</CHED>
<ROW>
<ENT I="01">Replace lockwire</ENT>
<ENT>.5
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