[Federal Register Volume 90, Number 124 (Tuesday, July 1, 2025)]
[Rules and Regulations]
[Pages 27977-27979]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2025-12245]
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DEPARTMENT OF TRANSPORTATION
Federal Aviation Administration
14 CFR Part 39
[Docket No. FAA-2025-0619; Project Identifier MCAI-2024-00372-T;
Amendment 39-23070; AD 2025-13-04]
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.
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SUMMARY: The FAA is adopting a new airworthiness directive (AD) for all
MHI RJ Aviation ULC Model CL-600-2C10 (Regional Jet Series 700, 701, &
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 an engine
indicating and crew alerting system (EICAS) STAB TRIM Caution message
that was posted, and subsequent repair that found prematurely worn
teeth on a rubber bull gear (RBG) wheel in the horizontal stabilizer
trim actuator (HSTA). This AD requires an inspection for part numbers
and on-condition replacement of affected RBG wheels. This AD also
prohibits the installation of affected parts under certain conditions.
The FAA is issuing this AD to address the unsafe condition on these
products.
DATES: This AD is effective August 5, 2025.
The Director of the Federal Register approved the incorporation by
reference of a certain publication listed in this AD as of August 5,
2025.
ADDRESSES:
AD Docket: You may examine the AD docket at regulations.gov under
Docket No. FAA-2025-0619; 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 Transport Canada material identified in this AD,
contact Transport Canada, Transport Canada National Aircraft
Certification, 159 Cleopatra Drive, Nepean, Ontario K1A 0N5, Canada;
telephone 888-663-3639; email [email protected]. You may find this material on the
Transport Canada website at tc.canada.ca/en/aviation.
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-2025-0619.
FOR FURTHER INFORMATION CONTACT: Isabel Saltzman, Aviation Safety
Engineer, FAA, 1600 Stewart Avenue, Suite 410, Westbury, NY 11590;
phone: 516-228-7300; email: [email protected].
SUPPLEMENTARY INFORMATION:
Background
The FAA issued a notice of proposed rulemaking (NPRM) to amend 14
CFR part 39 by adding an AD that would apply to all MHI RJ Aviation ULC
(type certificate previously held by Bombardier Inc.) Model CL-600-2C10
(Regional Jet Series 700, 701, & 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 was published in the Federal Register on April 15, 2025 (90 FR
15664). The NPRM was prompted by AD CF-2024-25, dated June 28, 2024
(Transport Canada AD CF-2024-25) (also referred to as ``the MCAI''),
issued by Transport Canada, which is the aviation authority for Canada.
The MCAI states that an in-service event occurred where an EICAS STAB
TRIM Caution message was posted. Subsequent repair found prematurely
worn teeth on an RBG wheel in the HSTA. Investigation determined that
this quality issue affects a limited number of RBG wheels and HSTA
serial numbers. Wear of the RBG wheel teeth could cause a failure of
the horizontal stabilizer trim system.
In the NPRM, the FAA proposed to require an inspection for part
numbers and on-condition replacement of affected RBG wheels, as
specified in Transport Canada AD CF-2024-25. The NPRM also proposed to
prohibit the installation of affected parts under certain conditions,
as specified in Transport Canada AD CF-2024-25. The FAA is issuing this
AD to address the unsafe condition on these products.
You may examine the MCAI in the AD docket at regulations.gov under
Docket No. FAA-2025-0619.
Discussion of Final Airworthiness Directive
Comments
The FAA received comments from Air Line Pilots Association,
International, and an individual, who both supported the NPRM without
change.
Conclusion
These products have been approved by the civil 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, that authority has notified the FAA of the unsafe condition
described in the MCAI referenced above. The FAA reviewed the relevant
data, considered any 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 these products. This AD is
adopted as proposed in the NPRM.
Material Incorporated by Reference Under 1 CFR Part 51
The FAA reviewed Transport Canada AD CF-2024-25, which specifies
procedures for a part number check and, if necessary, replacement of
affected RBG wheels in certain HSTAs. Transport Canada AD CF-2025-24
also prohibits the installation of affected parts under certain
conditions. 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 460 airplanes of U.S.
registry. The FAA estimates the following costs to comply with this AD:
[[Page 27978]]
Estimated Costs for Required Actions
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Labor cost Parts cost Cost per product Cost on U.S. operators
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1 work-hour x $85 per hour = $85....... None....................... $85 $39,100
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The FAA estimates the following costs to do any on-condition
replacement that would be required based on the results of determining
whether the part is an affected part. The FAA has no way of determining
the number of airplanes that might need this replacement:
Estimated Costs of On-Condition Actions
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Labor cost Parts cost Cost per product
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30 work-hours x $85 per hour = * $0 At least $2,550 (up to
$2,550. 32 affected parts in
the fleet).
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* The FAA has received no definitive data on which to base the cost
estimates for the on-condition parts specified in this AD.
The FAA has included all known costs in its cost estimate.
According to the manufacturer, however, some or all 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,
(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(g), 40113, 44701.
Sec. 39.13 [Amended]
0
2. The FAA amends Sec. 39.13 by adding the following new airworthiness
directive:
2025-13-04 MHI RJ Aviation ULC (Type Certificate Previously Held by
Bombardier Inc.): Amendment 39-23070; Docket No. FAA-2025-0619;
Project Identifier MCAI-2024-00372-T.
(a) Effective Date
This airworthiness directive (AD) is effective August 5, 2025.
(b) Affected ADs
None.
(c) Applicability
This AD applies to all MHI RJ Aviation ULC (Type Certificate
previously held by Bombardier Inc.) airplanes identified in
paragraphs (c)(1) through (5) of this AD, certificated in any
category.
(1) Model CL-600-2C10 (Regional Jet Series 700, 701, & 702)
airplanes.
(2) Model CL-600-2C11 (Regional Jet Series 550) airplanes.
(3) Model CL-600-2D15 (Regional Jet Series 705) airplanes.
(4) Model CL-600-2D24 (Regional Jet Series 900) airplanes.
(5) Model CL-600-2E25 (Regional Jet Series 1000) airplanes.
(d) Subject
Air Transport Association (ATA) of America Code 27, Flight
Controls.
(e) Unsafe Condition
This AD was prompted by a report of an in-service event where an
engine indicating and crew alerting system STAB TRIM Caution message
was posted, and subsequent repair found prematurely worn teeth on a
rubber bull gear (RBG) wheel in the horizontal stabilizer trim
actuator. The FAA is issuing this AD to address premature wear of
the RBG wheel teeth. The unsafe condition, if not addressed, could
result in a failure of the horizontal stabilizer trim system.
(f) Compliance
Comply with this AD within the compliance times specified,
unless already done.
(g) Requirements
Except as specified in paragraphs (h) and (i) of this AD: Comply
with all required actions and compliance times specified in, and in
accordance with, Transport Canada AD CF-2024-25, dated June 28, 2024
(Transport Canada AD CF-2024-25).
(h) Exceptions to Transport Canada AD CF-2024-25
(1) Where Transport Canada AD CF-2024-25 refers to its effective
date, this AD requires using the effective date of this AD.
(2) Where Transport Canada AD CF-2024-25 refers to ``Section
1.A. of the applicable MHIRJ SB'', this AD requires replacing that
text with ``Section 1.A. of MHIRJ Service Bulletin 670BA-27-077,
dated April 16, 2024''.
(i) Additional AD Provisions
The following provisions also apply to this AD:
(1) Alternative Methods of Compliance (AMOCs): The Manager,
International Validation Branch, FAA, has the authority to approve
AMOCs for this AD, if requested using the procedures found in 14 CFR
39.19. In accordance with 14 CFR 39.19, send your request to your
principal inspector or
[[Page 27979]]
responsible Flight Standards 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: [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's Transport
Canada Design Approval Organization (DAO). If approved by the DAO,
the approval must include the DAO-authorized signature.
(j) Additional Information
For more information about this AD, contact Isabel Saltzman,
Aviation Safety Engineer, FAA, 1600 Stewart Avenue, Suite 410,
Westbury, NY 11590; phone: 516-228-7300; email: [email protected].
(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 this AD specifies otherwise.
(i) Transport Canada AD CF-2024-25, dated June 28, 2024.
(ii) [Reserved]
(3) For Transport Canada material identified in this AD, contact
Transport Canada, Transport Canada National Aircraft Certification,
159 Cleopatra Drive, Nepean, Ontario K1A 0N5, Canada; telephone 888-
663-3639; email [email protected]. 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, 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/[email protected]">www.archives.gov/federal-register/cfr/[email protected].
Issued on June 18, 2025.
Steven W. Thompson,
Acting Deputy Director, Compliance & Airworthiness Division, Aircraft
Certification Service.
[FR Doc. 2025-12245 Filed 6-30-25; 8:45 am]
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