[Federal Register Volume 90, Number 118 (Monday, June 23, 2025)]
[Proposed Rules]
[Pages 26466-26469]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2025-11417]
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DEPARTMENT OF TRANSPORTATION
Federal Aviation Administration
14 CFR Part 39
[Docket No. FAA-2025-0482; Project Identifier MCAI-2024-00152-T]
RIN 2120-AA64
Airworthiness Directives; De Havilland Aircraft of Canada Limited
(Type Certificate Previously Held by Bombardier, Inc.) Airplanes
AGENCY: Federal Aviation Administration (FAA), DOT.
ACTION: Notice of proposed rulemaking (NPRM).
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SUMMARY: The FAA proposes to supersede Airworthiness Directive (AD)
2019-16-09, which applies to certain De Havilland Aircraft of Canada
Limited Model DHC-8-400 series airplanes. AD 2019-16-09 requires one-
time inspections for cracks and damage of the elevator power control
unit (PCU) brackets and surrounding area, horizontal stabilizer rear
spar, and elevator front spar, and related investigative and corrective
actions if necessary. Since the FAA issued AD 2019-16-09, new findings
have been reported as a result of maintenance activities and/or
inspections. This proposed AD would continue to require certain actions
in AD 2019-16-09, and would also require repeating the inspections one
time and performing applicable on-condition actions, remove an airplane
from the applicability, and provide optional terminating action for the
repetitive inspections. The FAA is proposing this AD to address the
unsafe condition on these products.
DATES: The FAA must receive comments on this proposed AD by August 7,
2025.
ADDRESSES: 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-2025-0482; 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.
Material Incorporated by Reference:
For Transport Canada material identified in this proposed
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. It is also
available at regulations.gov under Docket No. FAA-2025-0482.
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.
FOR FURTHER INFORMATION CONTACT: Yaser Osman, Aviation Safety Engineer,
FAA, 1600 Stewart Avenue, Suite 410, Westbury, NY 11590; telephone 516-
228-7300; email [email protected].
SUPPLEMENTARY INFORMATION:
Comments Invited
The FAA invites you to send any written relevant data, views, or
arguments about this proposal. Send your comments to an address listed
under the ADDRESSES section. Include ``Docket No. FAA-2025-0482;
Project Identifier MCAI-2024-00152-T'' at the beginning of your
comments. The most helpful comments reference a specific portion of the
proposal, explain the reason for any recommended change,
[[Page 26467]]
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
regulations.gov, including any personal information you provide. The
agency will also post a report summarizing each substantive verbal
contact received about this NPRM.
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 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 Yaser
Osman, Aviation Safety Engineer, FAA, 1600 Stewart Avenue, Suite 410,
Westbury, NY 11590; telephone 516-228-7300; email [email protected]. Any commentary that the FAA receives which is not
specifically designated as CBI will be placed in the public docket for
this rulemaking.
Background
The FAA issued AD 2019-16-09, Amendment 39-19712 (84 FR 46434,
September 4, 2019) (AD 2019-16-09), for certain De Havilland Aircraft
of Canada Limited Model DHC-8-400, -401, and -402 airplanes. AD 2019-
16-09 was prompted by an MCAI originated by Transport Canada, which is
the aviation authority for Canada. Transport Canada issued AD CF-2018-
34, dated December 17, 2018 (Transport Canada AD CF-2018-34), to
correct an unsafe condition.
AD 2019-16-09 requires one-time inspections for cracks and damage
of the elevator PCU fittings (brackets) and surrounding area,
horizontal stabilizer rear spar, and elevator front spar, and related
investigative and corrective actions if necessary. The FAA issued AD
2019-16-09 to address failure of an elevator PCU fitting (bracket) or
fracture of the front spar into two segments; either structural failure
may cause a jam in one elevator or a loss of airplane pitch control if
both elevators are affected.
Actions Since AD 2019-16-09 Was Issued
Since the FAA issued AD 2019-16-09, Transport Canada superseded AD
CF-2018-34 and issued Transport Canada AD CF-2024-10, dated March 1,
2024 (Transport Canada AD CF-2024-10), to correct an unsafe condition
for certain De Havilland Aircraft of Canada Limited Model DHC-8-401 and
-402 airplanes. Transport Canada AD CF-2024-10 states that new findings
have been reported as a result of maintenance activities and/or
inspections performed in accordance with De Havilland Aircraft of
Canada Limited Service Bulletin 84-55-09, dated June 7, 2018 (the
service information required by FAA AD 2019-16-09). Transport Canada AD
CF-2024-10 requires repeating the inspections one time and performing
applicable on-condition actions, while maintaining the requirements of
AD 2019-16-09. Transport Canada AD CF-2024-10 also removes the
requirement to report findings to the manufacturer.
Transport Canada also issued AD CF-2025-19, dated March 24, 2025
(Transport Canada AD CF-2025-19), which provides a new design solution
to address the unsafe condition identified in this NPRM and terminates
the actions specified in Transport Canada AD CF-2024-10.
The FAA is proposing this AD to address the unsafe condition on
these products. You may examine Transport Canada ADs CF-2024-10 and CF-
2025-19 in the AD docket at regulations.gov under Docket No. FAA-2025-
0482.
Explanation of Retained Requirements
Although this proposed AD does not explicitly restate the
requirements of AD 2019-16-09, this proposed AD would retain certain
requirements of AD 2019-16-09. Those requirements are referenced in
Transport Canada AD CF-2024-10, which, in turn, is referenced in
paragraph (g) of this proposed AD.
Material Incorporated by Reference Under 1 CFR Part 51
Transport Canada AD CF-2024-10 specifies procedures for performing
detailed visual and fluorescent penetrant inspections for cracks and
damage of the elevator PCU fittings (brackets), horizontal stabilizer
rear spar, and elevator front spar; repeating the inspections one time;
rectifying any cracked or damaged elevator PCU fitting (bracket) (which
includes replacing the elevator PCU fitting (bracket) and performing
related investigative and corrective actions including performing an
eddy current inspection for cracking of certain mating holes of the
horizontal stabilizer rear spar); and repairing any cracked or damaged
horizontal stabilizer rear spar assembly.
Transport Canada AD CF-2025-19 specifies procedures for, among
other actions, replacement of existing PCU fittings with redesigned PCU
fittings. The replacement includes detailed inspections for damage and
eddy current inspections for cracking, repair, installation of new
bushings, and installation of doublers.
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
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 Transport
Canada AD CF-2024-10 referenced above. The FAA is issuing this NPRM
after determining that the unsafe condition described previously is
likely to exist or develop in other products of the same type design.
Proposed AD Requirements in This NPRM
This proposed AD would retain certain requirements of AD 2019-16-
09. This proposed AD would remove an airplane from the applicability
and require accomplishing the actions specified in Transport Canada AD
CF-2024-10 described previously, except for any differences identified
as exceptions in the regulatory text of this proposed AD. This proposed
AD would also provide optional terminating action for the repetitive
inspections, as specified in Transport Canada AD CF-2025-19.
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, the
FAA proposes to
[[Page 26468]]
incorporate Transport Canada ADs CF-2024-10 by reference in the FAA
final rule. This proposed AD would, therefore, require compliance with
Transport Canada AD CF-2024-10 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 ADs CF-2024-10 for compliance will be available at
regulations.gov under Docket No. FAA-2025-0482 after the FAA final rule
is published.
Interim Action
The FAA considers that this proposed AD would be an interim action.
The FAA is considering mandating the optional terminating action
specified in Transport Canada AD CF-2025-19.
Costs of Compliance
The FAA estimates that this AD, if adopted as proposed, would
affect 54 airplanes of U.S. registry. The FAA estimates the following
costs to comply with this proposed AD:
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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13 work-hours x $85 per hour = $1,105.... $0 Up to $1,105............... Up to $59,670.
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Estimated Costs for Optional Actions
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Labor cost Parts cost Cost per product
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48 work-hours x $85 per hour = $16,343 $20,423
$4,080...........................
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The FAA estimates the following costs to do any necessary on-
condition actions that would be required based on the results of any
required actions. The FAA has no way of determining the number of
aircraft that might need this on-condition action:
Estimated Costs of On-Condition Actions
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Labor cost Parts cost Cost per product
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18 work-hours x $85 per hour = $14,233 $15,763
$1,530...........................
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The FAA has received no definitive data on which to base the cost
estimates for the on-condition repairs specified in this proposed AD.
According to the manufacturer, some or all of the costs of this
proposed AD may be covered under warranty, thereby reducing the cost
impact on affected individuals. The FAA does not control warranty
coverage for affected individuals. As a result, the FAA has included
all known costs in the cost estimate.
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
The FAA determined that this proposed AD would not have federalism
implications under Executive Order 13132. This proposed AD would 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 this proposed
regulation:
(1) Is not a ``significant regulatory action'' under Executive
Order 12866,
(2) Would not affect intrastate aviation in Alaska, and
(3) Would 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 Proposed Amendment
Accordingly, under the authority delegated to me by the
Administrator, the FAA proposes to amend 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:
0
a. Removing Airworthiness Directive (AD) 2019-16-09, Amendment 39-19712
(84 FR 46434, September 4, 2019); and
0
b. Adding the following new AD:
De Havilland Aircraft of Canada Limited (Type Certificate Previously
Held by Bombardier, Inc.): Docket No. FAA-2025-0482; Project
Identifier MCAI-2024-00152-T.
(a) Comments Due Date
The FAA must receive comments on this airworthiness directive
(AD) by August 7, 2025.
(b) Affected ADs
This AD replaces AD 2019-16-09, Amendment 39-19712 (84 FR 46434,
September 4, 2019) (AD 2019-16-09).
[[Page 26469]]
(c) Applicability
This AD applies to De Havilland Aircraft of Canada Limited (type
certificate previously held by Bombardier, Inc.) Model DHC-8-401 and
-402 airplanes, certificated in any category, as identified in
Transport Canada AD CF-2024-10, dated March 1, 2024 (Transport
Canada AD CF-2024-10).
(d) Subject
Air Transport Association (ATA) of America Code 27, Flight
controls.
(e) Unsafe Condition
This AD was prompted by reports of cracked elevator power
control unit (PCU) fittings (brackets) on the horizontal stabilizer
rear spar and cracking on the elevator front spar. The FAA is
issuing this AD to address this condition, which, if not detected
and corrected, may cause failure of an elevator PCU fitting
(bracket) or fracture the front spar into two segments; either
structural failure may cause a jam in one elevator or a loss of
airplane pitch control if both elevators are affected.
(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-2024-10.
(h) Exceptions to Transport Canada AD CF-2024-10
(1) Where Transport Canada AD CF-2024-10 refers to ``the
effective date of AD CF-2018-34 (31 December 2018),'' this AD
requires using October 8, 2019 (the effective date of AD 2019-16-
09).
(2) Where Transport Canada AD CF-2024-10 refers to hours air
time, this AD requires using flight hours.
(3) Where Transport Canada AD CF-2024-10 refers to ``if cracks
or damage'', this AD requires replacing that text with ``if any
crack or damage''.
(4) Where Transport Canada AD CF-2024-10 specifies actions if
certain conditions are found on ``rear spar assembly P/N 85517044
and/or elevator assembly P/N 85527021'', this AD requires replacing
that text with ``rear spar assembly P/N 85517044 or elevator
assembly P/N 85527021''.
(5) Where Transport Canada AD CF-2024-10 specifies ``after
inspecting as required by AD CF-2018-34'', this AD requires
replacing that text with ``after inspecting as specified in
Bombardier Service Bulletin 84-55-09 or de Havilland Aircraft of
Canada Limited Service Bulletin 84-55-09''.
(6) Where paragraph B. of Part I and paragraph A. of Part II of
Transport Canada AD CF-2024-10 specify a compliance time to do a
repeat inspection, this AD allows the inspection to be done within
90 days after the effective date of this AD.
(i) No Reporting Requirement
Although the material referenced in Transport Canada AD CF-2024-
10 specifies to submit certain information to the manufacturer, this
AD does not include that requirement.
(j) Optional Terminating Action for Repetitive Inspections
(1) For airplane serial numbers 4001 and 4003 through 4058
inclusive on which any inspection specified in Section 3.B. of the
Accomplishment Instructions of Bombardier Service Bulletin 84-55-09
or de Havilland Aircraft of Canada Limited Service Bulletin 84-55-09
has been done: Replacement of existing PCU fittings with redesigned
PCU fittings in accordance with Part I, paragraph B., of Transport
Canada AD CF-2025-19, dated March 24, 2025, terminates the
requirements of paragraph (g) of this AD.
(2) For airplane serial numbers 4059 through 4580 inclusive on
which any inspection specified in Section 3.B. of the Accomplishment
Instructions of Bombardier Service Bulletin 84-55-09 or de Havilland
Aircraft of Canada Limited Service Bulletin 84-55-09 has been done:
Replacement of existing PCU fittings with redesigned PCU fittings in
accordance with Part II, paragraphs B. and C., of Transport Canada
AD CF-2025-19, dated March 24, 2025, terminates the requirements of
paragraph (g) of this AD.
(k) Credit for Previous Actions
This paragraph provides credit for the actions specified in
paragraph A. of Part I of Transport Canada AD CF-2024-10, as
required by paragraph (g) of this AD, if those actions were
performed before the effective date of this AD using Bombardier
Service Bulletin 84-55-09, dated June 7, 2018; or de Havilland
Aircraft of Canada Limited Service Bulletin 84-55-09, Revision A,
dated January 10, 2020.
(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,
International Validation Branch, send it to the attention of the
person identified in paragraph (m)(1) of this AD and email to:
[email protected].
(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 De Havilland
Aircraft of Canada Limited'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 Yaser Osman,
Aviation Safety Engineer, FAA, 1600 Stewart Avenue, Suite 410,
Westbury, NY 11590; telephone 516-228-7300; email [email protected].
(2) For Bombardier or De Havilland Aircraft of Canada Limited
material identified in this AD that is not incorporated by
reference, contact De Havilland Aircraft of Canada Limited, Dash 8
Series Customer Response Centre, 5800 Explorer Drive, Mississauga,
Ontario, L4W 5K9, Canada; telephone North America (toll-free): 855-
310-1013, Direct: 647-277-5820; email dehavilland.com">thd@dehavilland.com; website
dehavilland.com.
(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) Transport Canada AD CF-2024-10, dated March 1, 2024.
(ii) Transport Canada AD CF-2025-19, dated March 24, 2025.
(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/ibr-locations, or email [email protected].
Issued on June 16, 2025.
Paul R. Bernado,
Acting Director, Compliance & Airworthiness Division, Aircraft
Certification Service.
[FR Doc. 2025-11417 Filed 6-20-25; 8:45 am]
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