[Federal Register Volume 90, Number 130 (Thursday, July 10, 2025)]
[Rules and Regulations]
[Pages 30585-30588]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2025-12860]


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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2025-1356; Project Identifier MCAI-2025-00834-T; 
Amendment 39-23080; AD 2025-14-02]
RIN 2120-AA64


Airworthiness Directives; Airbus SAS Airplanes

AGENCY: Federal Aviation Administration (FAA), DOT.

[[Page 30586]]


ACTION: Final rule; request for comments.

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SUMMARY: The FAA is adopting a new airworthiness directive (AD) for all 
Airbus SAS Model A350-941 and -1041 airplanes. This AD was prompted by 
a design review that identified a potential thrust asymmetry condition 
during derated takeoff operations under certain conditions. This AD 
requires revising the existing airplane flight manual (AFM) to provide 
the flightcrew with procedures for derated takeoff limitations. The FAA 
is issuing this AD to address the unsafe condition on these products.

DATES: This AD is effective July 25, 2025.
    The Director of the Federal Register approved the incorporation by 
reference of a certain publication listed in this AD as of July 25, 
2025.
    The FAA must receive comments on this AD by August 25, 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-2025-1356; 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.
    Material Incorporated by Reference:
     For European Union Aviation Safety Agency (EASA) material 
identified in this AD, contact EASA, Konrad-Adenauer-Ufer 3, 50668 
Cologne, Germany; telephone +49 221 8999 000; email [email protected]. 
You may find this material on the EASA website at ad.easa.europa.eu.
     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-2025-1356.

FOR FURTHER INFORMATION CONTACT: Anthony Decaro, Aviation Safety 
Engineer, FAA, 2200 South 216th St., Des Moines, WA 98198; phone: 562-
627-5374; email: [email protected].

SUPPLEMENTARY INFORMATION:

Comments Invited

    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 ADDRESSES section. Include ``Docket No. FAA-2025-1356; Project 
Identifier MCAI-2025-00834-T'' 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 
regulations.gov, including any personal information you provide. The 
agency will also post a report summarizing each substantive verbal 
contact received about this final rule.

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 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 Anthony 
Decaro, Aviation Safety Engineer, FAA, 2200 South 216th St., Des 
Moines, WA 98198; phone: 562-627-5374; 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

    EASA, which is the Technical Agent for the Member States of the 
European Union, has issued EASA AD 2025-0105, dated May 7, 2025 (EASA 
AD 2025-0105) (also referred to as ``the MCAI''), to correct an unsafe 
condition on all Airbus SAS Model A350-941 and -1041 airplanes. The 
MCAI states that, during a design review, a potential thrust asymmetry 
condition was identified during derated takeoff operations when one 
engine is operating within a restricted N1 zone due to keep out zone 
(KOZ) limitations. Investigation revealed that the root cause lies in 
the interaction between derated logic and KOZ-limited engine control 
laws, which may result in significant thrust differences between 
engines. This condition, if not corrected, could lead to increased 
flightcrew workload during critical phases of flight, possibly 
resulting in reduced control of the airplane.
    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-2025-1356.

Material Incorporated by Reference Under 1 CFR Part 51

    The FAA reviewed EASA AD 2025-0105. This material specifies 
revising the limitations section of the existing AFM to provide the 
flightcrew with procedures for derated takeoff limitations.
    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

    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 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.

Requirements of This AD

    This AD requires accomplishing the actions specified in EASA AD 
2025-0105 described previously, except for any differences identified 
as exceptions in the regulatory text of this AD.

[[Page 30587]]

Compliance With AFM Revision

    EASA AD 2025-0105 requires operators to ``inform all flight crews'' 
of revisions to the AFM, and thereafter to ``operate the aeroplane 
accordingly.'' However, this AD does not specifically require those 
actions as those actions are already required by FAA regulations. FAA 
regulations require that operators furnish to pilots any changes to the 
AFM (for example, 14 CFR 121.137) and ensure the pilots are familiar 
with the AFM (for example, 14 CFR 91.505). As with any other flightcrew 
training requirement, training on the updated AFM content is tracked by 
the operators and recorded in each pilot's training record, which is 
available for the FAA to review. FAA regulations also require pilots to 
follow the procedures in the AFM including all updates. Section 91.9 
requires that any person operating a civil aircraft must comply with 
the operating limitations specified in the AFM. Therefore, including a 
requirement in this AD to operate the airplane according to the revised 
AFM would be redundant and unnecessary.

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, 
EASA AD 2025-0105 is incorporated by reference in this AD. This AD 
requires compliance with EASA AD 2025-0105 in its entirety through that 
incorporation, except for any differences identified as exceptions in 
the regulatory text of this AD. Using common terms that are the same as 
the heading of a particular section in EASA AD 2025-0105 does not mean 
that operators need comply only with that section. For example, where 
the AD requirement refers to ``all required actions and compliance 
times,'' compliance with this AD requirement is not limited to the 
section titled ``Required Action(s) and Compliance Time(s)'' in EASA AD 
2025-0105. Material required by EASA AD 2025-0105 for compliance will 
be available at regulations.gov under Docket No. FAA-2025-1356 after 
this AD is published.

Justification for Immediate Adoption and Determination of the Effective 
Date

    Section 553(b) of the Administrative Procedure Act (APA) (5 U.S.C. 
551 et seq.) 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 interaction between derated takeoff logic and KOZ-limited 
engine control laws can cause significant thrust differences between 
engines (asymmetric thrust). During critical phases of flight this can 
lead to increased flightcrew workload and loss of control of the 
airplane. Additionally, the compliance time in this AD is shorter than 
the time necessary for the public to comment and for publication of the 
final rule. Accordingly, notice and opportunity for prior public 
comment are impracticable and contrary to the public interest pursuant 
to 5 U.S.C. 553(b).
    In addition, the FAA finds that good cause exists pursuant to 5 
U.S.C. 553(d) for making this amendment effective in less than 30 days, 
for the same reasons the FAA found good cause to forgo notice and 
comment.

Regulatory Flexibility Act (RFA)

    The requirements of the RFA do not apply when an agency finds good 
cause pursuant to 5 U.S.C. 553 to adopt a rule without prior notice and 
comment. Because the FAA has determined that it has good cause to adopt 
this rule without notice and comment, RFA analysis is not required.

Costs of Compliance

    The FAA estimates that this AD affects 37 airplanes of U.S. 
registry. The FAA estimates the following costs to comply with this AD:

                                      Estimated Costs for Revising the AFM
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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...................           $0                  $85                    $3,145
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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, and
    (2) Will not affect intrastate aviation in Alaska.

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:

[[Page 30588]]

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:

2025-14-02 Airbus SAS: Amendment 39-23080; Docket No. FAA-2025-1356; 
Project Identifier MCAI-2025-00834-T.

(a) Effective Date

    This airworthiness directive (AD) is effective July 25, 2025.

(b) Affected ADs

    None.

(c) Applicability

    This AD applies to all Airbus SAS Model A350-941 and -1041 
airplanes, certificated in any category.

(d) Subject

    Air Transport Association (ATA) of America Code 76, Engine 
Controls.

(e) Unsafe Condition

    This AD was prompted by a design review that identified a 
potential thrust asymmetry condition during derated takeoff 
operations when one engine is operating within a restricted N1 zone 
due to keep out zone (KOZ) limitations. The FAA is issuing this AD 
to address significant thrust differences between engines caused by 
the interaction between derated takeoff logic and KOZ-limited engine 
control laws. This condition, if not corrected, could lead to 
increased flightcrew workload during critical phases of flight, 
resulting in reduced control of the airplane.

(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, European Union Aviation Safety Agency (EASA) AD 
2025-0105, dated May 7, 2025 (EASA AD 2025-0105).

(h) Exceptions to EASA AD 2025-0105

    (1) Where EASA AD 2025-0105 refers to its effective date, this 
AD requires using the effective date of this AD.
    (2) Where paragraph (1) of EASA AD 2025-0105 specifies to 
``inform all flight crews, and, thereafter, operate the aeroplane 
accordingly,'' this AD does not require those actions as those 
actions are already required by existing FAA operating regulations 
(see 14 CFR 91.9, 91.505, and 121.137).
    (3) Where paragraph (2) of EASA AD 2025-0105 specifies ``which 
includes the same content as the AFM TR'', this AD requires 
replacing that text with ``which includes information identical to 
the information in the AFM TR''.
    (4) This AD does not adopt the ``Remarks'' section of EASA AD 
2025-0105.

(i) 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 (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, AIR-520, 
Continued Operational Safety Branch, FAA; or EASA; or Airbus SAS's 
EASA Design Organization Approval (DOA). If approved by the DOA, the 
approval must include the DOA-authorized signature.

(j) Additional Information

    For more information about this AD, contact Anthony Decaro, 
Aviation Safety Engineer, FAA, 2200 South 216th St., Des Moines, WA 
98198; phone: 562-627-5374; 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) European Union Aviation Safety Agency (EASA) AD 2025-0105, 
dated May 7, 2025.
    (ii) [Reserved]
    (3) For EASA material identified in this AD, contact EASA, 
Konrad-Adenauer-Ufer 3, 50668 Cologne, Germany; telephone +49 221 
8999 000; email [email protected]. You may find this material on 
the EASA website at ad.easa.europa.eu.
    (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 July 2, 2025.
Lona C. Saccomando,
Acting Deputy Director, Integrated Certificate Management Division, 
Aircraft Certification Service.
[FR Doc. 2025-12860 Filed 7-8-25; 4:15 pm]
BILLING CODE 4910-13-P