[Federal Register Volume 90, Number 155 (Thursday, August 14, 2025)]
[Rules and Regulations]
[Pages 39090-39093]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2025-15478]


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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2024-0454; Project Identifier MCAI-2023-00923-T; 
Amendment 39-23098; AD 2025-16-01]
RIN 2120-AA64


Airworthiness Directives; Airbus Canada Limited Partnership (Type 
Certificate Previously Held by C Series Aircraft Limited Partnership 
(CSALP); 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 
Airbus Canada Limited Partnership Model BD-500-1A10 and BD-500-1A11 
airplanes. This AD was prompted by a report of multiple in-service 
failures of engine feed check valves, which have resulted in fuel 
imbalance conditions in flight. This AD requires repetitive replacement 
of the left-and right-side engine feed check valves with new engine 
feed check valves and prohibits flight dispatch under certain 
conditions. The FAA is issuing this AD to address the unsafe condition 
on these products.

DATES: This AD is effective September 18, 2025.
    The Director of the Federal Register approved the incorporation by 
reference of a certain publication listed in this AD as of September 
18, 2025.

ADDRESSES: 
    AD Docket: You may examine the AD docket at regulations.gov under 
Docket No. FAA-2024-0454; 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-2024-0454.

FOR FURTHER INFORMATION CONTACT: Joseph Catanzaro, Aviation Safety 
Engineer, FAA, 2200 South 216th St., Des Moines, WA 98198; telephone 
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 Airbus Canada 
Limited Partnership Model BD-500-1A10 and BD-500-1A11 airplanes. The 
NPRM was published in the Federal Register on March 7, 2024 (89 FR 
16486). The NPRM was prompted by AD CF-2023-59, dated July 26, 2023, 
issued by Transport Canada, which is the aviation authority for Canada 
(Transport Canada AD CF-2023-59). Transport Canada AD CF-2023-59 states 
that there have been multiple in-service failures of engine feed check 
valves, which have resulted in fuel imbalance conditions in flight. An 
investigation found that the engine feed check valve is subject to 
abnormal wear-out failures due to a severe operating environment in the 
engine fuel feed line. In the event of a failure of the check valve, 
flapper valve assembly items can become dislodged and contaminate the 
fuel system, potentially resulting in severe fuel imbalance or loss of 
fuel flow to the engine.
    In the NPRM, the FAA proposed to require repetitive replacement of 
the left- and right-side engine feed check valves with new engine feed 
check valves, as specified in Transport Canada AD CF-2023-59.
    You may examine Transport Canada AD CF-2023-59 in the AD docket at 
regulations.gov under Docket No. FAA-2024-0454.
    The FAA issued a supplemental notice of proposed rulemaking (SNPRM) 
to amend 14 CFR part 39 by adding an AD that would apply to all Airbus 
Canada Limited Partnership Model BD-500-1A10 and BD-500-1A11 airplanes. 
The SNPRM was published in the Federal Register on April 1, 2025 (90 FR 
14343). The SNPRM was prompted by Transport Canada superseding 
Transport Canada AD CF-2023-59, and issuing Transport Canada AD CF-
2024-20, dated June 5, 2024 (Transport Canada AD CF-2024-20) (also 
referred to as the MCAI). Transport Canada AD CF-2024-20 states that 
since issuance of Transport Canada AD CF-2023-59, the manufacturer 
determined that dispatching with either the left or right fuel 
alternating current (AC) boost pump inoperative can further exacerbate 
the risk of severe fuel imbalance, potentially leading to loss of fuel 
flow to both engines. The manufacturer issued Flight Operations 
Transmission (FOT) A220-FOT-28-00-001 to raise awareness of this issue 
and recommend certain dispatch restrictions. The MCAI retains the 
requirements of Transport Canada AD CF-2023-59, which is superseded, 
and prohibits dispatch with either the left or right fuel AC boost pump 
inoperative. In the SNPRM, the FAA proposed to require repetitive 
replacement of the left- and right-side engine feed check valves with 
new engine feed check valves and prohibit flight dispatch under certain 
conditions, as specified in Transport Canada AD CF-2024-20. The FAA is 
issuing this AD to address failure of the check valve. The unsafe 
condition, if not addressed, could result in severe fuel imbalance or 
loss of fuel flow to one or both engines.

Discussion of Final Airworthiness Directive

Comments

    The FAA received comments from Air Line Pilots Association, 
International (ALPA) and JetBlue. The following presents the comments 
received on the SNPRM and the FAA's response to each comment.

Request To Remove ``Or Later Revision''

    ALPA, while supporting other parts of the proposed AD, disagreed 
with allowing later revisions of service information as compliance 
documents as specified in the MCAI. ALPA stated that it does not 
support referencing a service bulletin that has not been finalized.
    The FAA agrees to clarify. This AD refers to Transport Canada AD 
CF-2024-20, as the appropriate source of

[[Page 39091]]

service information for accomplishing the required actions. Transport 
Canada AD CF-2024-20 specifies to use certain service information ``or 
later revisions approved by the Chief, Continuing Airworthiness, 
Transport Canada.'' That phrase indicates that service information must 
be finalized and approved by a regulatory authority (Transport Canada, 
which is the state of design authority in this case) before it may be 
used to show compliance with this AD. Referring to the MCAI instead of 
a service bulletin minimizes the need for Alternative Methods of 
Compliance. No change has been made to the AD in this regard.

Request for Revision of Paragraph Header for Paragraph (i) of the 
Proposed AD

    JetBlue requested a revision to the header of paragraph (i) of the 
proposed AD from ``Terminating Action for AD 2023-16-02'' to ``Changes 
for Repeat Inspection for AD 2023-16-02.'' JetBlue reasoned that its 
requested change is necessary because the proposed AD wouldn't 
terminate AD 2023-16-02, Amendment 39-22521 (88 FR 56459, August 18, 
2023) (AD 2023-16-02), instead it allows a change to the repetitive 
inspection by use of a concurrent action.
    The FAA agrees to revise the header of paragraph (i) of this AD, to 
clarify that the actions are not terminating. The FAA has revised the 
text to ``Method of Compliance for Certain Action in AD 2023-16-02.''

Request To Clarify Number of Affected Check Valves for a Condition

    JetBlue requested an edit to paragraph (i)(2) of the proposed AD to 
clarify the number of check valves that may qualify for relief from 
certain requirements. JetBlue suggested that the language in paragraph 
(i)(2) of the proposed AD added ambiguity to the number of check valves 
and suggested revised language that would clarify the valves that are 
affected by both ADs, i.e., change the text from ``Only one check valve 
. . .'' to ``Only the replaced check valve . . .''.
    The FAA agrees to revise paragraph (i)(2) of this AD as suggested 
but with one minor change. The FAA has replaced the text ``Only one 
check valve'' with ``Only the check valve'' so that paragraph (i)(2) of 
this AD now reads ``Only the check valve (P/N 2090199-101) that has 
been replaced as specified in paragraph (g) of this AD may be granted 
relief from the on-condition inspection and replacement requirements of 
AD 2023-16-02.''

Clarification of the Exception in Paragraph (h)(1) of This AD

    The compliance time exception in paragraph (h)(1) of the proposed 
AD only referred to the effective date of Transport Canada AD CF-2024-
20; however, it should have also referred to the effective date of 
Transport Canada AD CF-2023-59, dated July 26, 2023, which is referred 
to in paragraph A. of Transport Canada AD CF-2024-20. Therefore, the 
FAA has revised paragraph (h)(1) of this AD to specify that ``where 
Transport Canada AD CF-2024-20 refers to its effective date or to the 
effective date of AD CF-2023-59, this AD requires using the effective 
date of this AD.''

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. Except for 
minor editorial changes, and any other changes described previously, 
this AD is adopted as proposed in the SNPRM. None of the changes will 
increase the economic burden on any operator.

Material Incorporated by Reference Under 1 CFR Part 51

    The FAA reviewed Transport Canada AD CF-2024-20, which specifies 
procedures for repetitive replacement of the left- and right-side 
engine feed check valves with new engine feed check valves and 
prohibits dispatch with either the left or right fuel AC boost pump 
inoperative. 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.

Interim Action

    The FAA considers that this AD is an interim action. If final 
action is identified, the FAA might consider further rulemaking then.

Costs of Compliance

    The FAA estimates that this AD affects 91 airplanes of U.S. 
registry. The FAA estimates the following costs to comply with this 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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9 work-hours x $85 per hour = $765     $2,830 per replacement   $3,595 per replacement   $327,145 per
 per replacement cycle.                 cycle.                   cycle.                   replacement cycle.
----------------------------------------------------------------------------------------------------------------

    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

[[Page 39092]]

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:

2025-16-01 Airbus Canada Limited Partnership (Type Certificate 
Previously Held by C Series Aircraft Limited Partnership (CSALP); 
Bombardier, Inc.): Amendment 39-23098; Docket No. FAA-2024-0454; 
Project Identifier MCAI-2023-00923-T.

(a) Effective Date

    This airworthiness directive (AD) is effective September 18, 
2025.

(b) Affected ADs

    This AD affects AD 2023-16-02, Amendment 39-22521 (88 FR 56459, 
August 18, 2023) (AD 2023-16-02).

(c) Applicability

    This AD applies to all Airbus Canada Limited Partnership Model 
BD-500-1A10 and BD-500-1A11 airplanes, certificated in any category.

(d) Subject

    Air Transport Association (ATA) of America Code 28, Fuel.

(e) Unsafe Condition

    This AD was prompted by a report of multiple in-service failures 
of engine feed check valves, which have resulted in fuel imbalance 
conditions in flight. The FAA is issuing this AD to address failure 
of the check valve. The unsafe condition, if not addressed, could 
result in severe fuel imbalance or loss of fuel flow to one or both 
engines.

(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-2024-20, dated June 5, 2024 
(Transport Canada AD CF-2024-20).

(h) Exception to Transport Canada AD CF-2024-20

    (1) Where Transport Canada AD CF-2024-20 refers to its effective 
date or to the effective date of Transport Canada AD CF-2023-59, 
dated July 26, 2023, this AD requires using the effective date of 
this AD.
    (2) Where Transport Canada AD CF-2024-20 refers to hours air 
time, this AD requires using flight hours.

(i) Method of Compliance for Certain Action in AD 2023-16-02

    Accomplishing repetitive replacement of the engine isolation 
feed ejector check valve, P/N 2090199-101, as required by paragraph 
(g) of this AD is an acceptable means of complying with the 
repetitive on-condition inspection requirement of AD 2023-16-02 
provided that all of the conditions in paragraphs (i)(1) through (3) 
of this AD are satisfied.
    (1) Both the replacement and on-condition inspection required by 
paragraph (g) of this AD are accomplished concurrently at intervals 
not to exceed 3,000 flight hours after the most recent inspection 
performed in accordance with AD 2023-16-02.
    (2) Only the check valve (P/N 2090199-101) that has been 
replaced as specified in paragraph (g) of this AD may be granted 
relief from the on-condition inspection and replacement requirements 
of AD 2023-16-02.
    (3) All other applicable requirements of AD 2023-16-02 are 
complied with.

(j) Special Flight Permit

    Special flight permits may be issued in accordance with 14 CFR 
21.197 and 21.199 to operate the airplane to a location where the 
airplane can be modified, provided that only crew are onboard.

(k) Additional AD Provisions

    The following provisions also apply to this AD:
    (1) Alternative Methods of Compliance (AMOCs): The Manager, AIR-
520, Continued Operational Safety 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 of 
the Continued Operational Safety Branch, send it to the attention of 
the person identified in paragraph (l) 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, AIR-520, 
Continued Operational Safety Branch, FAA; or Transport Canada; or 
Airbus Canada's Transport Canada Design Approval Organization (DAO). 
If approved by the DAO, the approval must include the DAO-authorized 
signature.
    (3) Required for Compliance (RC): Except as required by 
paragraph (k)(2) of this AD, if any material contains procedures or 
tests that are identified as RC, those procedures and tests must be 
done to comply with this AD; any procedures or tests that are not 
identified as RC are recommended. Those procedures and tests that 
are not identified as RC may be deviated from using accepted methods 
in accordance with the operator's maintenance or inspection program 
without obtaining approval of an AMOC, provided the procedures and 
tests identified as RC can be done and the airplane can be put back 
in an airworthy condition. Any substitutions or changes to 
procedures or tests identified as RC require approval of an AMOC.

(l) Additional Information

    For more information about this AD, contact Joseph Catanzaro, 
Aviation Safety Engineer, FAA, 2200 South 216th St., Des Moines, WA 
98198; telephone 516-228-7300; email [email protected].

(m) 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-2024-20, dated June 5, 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/ibr-locations or email [email protected].


[[Page 39093]]


    Issued on July 30, 2025.
Peter A. White,
Deputy Director, Integrated Certificate Management Division, Aircraft 
Certification Service.
[FR Doc. 2025-15478 Filed 8-13-25; 8:45 am]
BILLING CODE 4910-13-P