[Federal Register Volume 89, Number 88 (Monday, May 6, 2024)]
[Rules and Regulations]
[Pages 37111-37113]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2024-09564]


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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2024-0030; Project Identifier AD-2023-01066-E; 
Amendment 39-22722; AD 2024-07-02]
RIN 2120-AA64


Airworthiness Directives; CFM International, S.A. Engines

AGENCY: Federal Aviation Administration (FAA), DOT.

ACTION: Final rule.

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SUMMARY: The FAA is adopting a new airworthiness directive (AD) for CFM 
International, S.A. (CFM) Model LEAP-1A23, LEAP-1A24, LEAP-1A24E1, 
LEAP-1A26, LEAP-1A26CJ, LEAP-1A26E1, LEAP-1A29, LEAP-1A29CJ, LEAP-1A30, 
LEAP-1A32, LEAP-1A33, LEAP-1A33B2, and LEAP-1A35A engines. This AD was 
prompted by detection of melt-related freckles in the billet, which may 
reduce the life of certain high-pressure turbine (HPT) rotor interstage 
seals. This AD requires removing the affected HPT rotor interstage 
seals from service and replacing with a part eligible for installation. 
The FAA is issuing this AD to address the unsafe condition on these 
products.

DATES: This AD is effective June 10, 2024.
    The Director of the Federal Register approved the incorporation by 
reference of a certain publication listed in this AD as of June 10, 
2024.

ADDRESSES: 
    AD Docket: You may examine the AD docket at regulations.gov under 
Docket No. FAA-2024-0030; 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, 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:

[[Page 37112]]

     For service information identified, contact CFM 
International, S.A., GE Aviation Fleet Support, 1 Neumann Way, M/D Room 
285, Cincinnati, OH 45215; phone: (877) 432-3272; email: 
[email protected].
     You may view this service information at the FAA, 
Airworthiness Products Section, Operational Safety Branch, 1200 
District Avenue, Burlington, MA 01803. For information on the 
availability of this material at the FAA, call (817) 222-5110. It is 
also available at regulations.gov under Docket No. FAA-2024-0030.

FOR FURTHER INFORMATION CONTACT: Mehdi Lamnyi, Aviation Safety 
Engineer, FAA, 2200 South 216th Street, Des Moines, WA 98198; phone: 
(781) 238-7743; 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 CFM Model LEAP-1A23, 
LEAP-1A24, LEAP-1A24E1, LEAP-1A26, LEAP-1A26CJ, LEAP-1A26E1, LEAP-1A29, 
LEAP-1A29CJ, LEAP-1A30, LEAP-1A32, LEAP-1A33, LEAP-1A33B2, and LEAP-
1A35A engines. The NPRM published in the Federal Register on January 
11, 2024 (89 FR 1847). The NPRM was prompted by detection of melt-
related freckles in the billet, which may reduce the life of certain 
HPT rotor interstage seals. In the NPRM, the FAA proposed to require 
removing the affected HPT rotor interstage seals from service and 
replacing with a part eligible for installation. The FAA is issuing 
this AD to address the unsafe condition on these products.

Discussion of Final Airworthiness Directive

Comments

    The FAA received no comments on the NPRM or on the determination of 
the costs.

Conclusion

    The FAA reviewed the relevant data 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, this AD is adopted as proposed in the NPRM.

Related Service Information Under 1 CFR Part 51

    The FAA reviewed CFM Service Bulletin LEAP-1A-72-00-0492-01A-930A-
D, Issue 001-00, dated April 6, 2023, which provides the serial numbers 
of the affected HPT rotor interstage seals and specifies procedures for 
replacement of the HPT rotor interstage seal. This service information 
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 1 engine installed on an 
airplane of U.S. registry.
    The FAA estimates the following costs to comply with this AD:

                                                 Estimated Costs
----------------------------------------------------------------------------------------------------------------
                                                                                    Cost per       Cost on U.S.
               Action                        Labor cost           Parts cost        product         operators
----------------------------------------------------------------------------------------------------------------
Remove HPT rotor interstage seal....  225 work-hours x $85           $168,000         $187,125         $187,125
                                       per hour = $19,125.
----------------------------------------------------------------------------------------------------------------

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:

2024-07-02 CFM International, S.A.: Amendment 39-22722; Docket No. 
FAA-2024-0030; Project Identifier AD-2023-01066-E.

(a) Effective Date

    This airworthiness directive (AD) is effective June 10, 2024.

(b) Affected ADs

    None.

(c) Applicability

    This AD applies to CFM International, S.A. (CFM) Model LEAP-
1A23, LEAP-1A24, LEAP-1A24E1, LEAP-1A26, LEAP-1A26CJ, LEAP-1A26E1, 
LEAP-1A29, LEAP-1A29CJ, LEAP-1A30, LEAP-1A32, LEAP-1A33, LEAP-
1A33B2, and LEAP-1A35A engines.

(d) Subject

    Joint Aircraft System Component (JASC) Code 7250, Turbine 
Section.

(e) Unsafe Condition

    This AD was prompted by detection of melt-related freckles in 
the billet, which may reduce the life of certain high-pressure

[[Page 37113]]

turbine (HPT) rotor interstage seals. The FAA is issuing this AD to 
prevent failure of the HPT rotor interstage seal. The unsafe 
condition, if not addressed, could result in release of uncontained 
debris, damage to the engine, and damage to the airplane.

(f) Compliance

    Comply with this AD within the compliance times specified, 
unless already done.

(g) Required Actions

    For engines with an affected HPT rotor interstage seal 
installed, before exceeding the applicable threshold specified in 
Table 1 of paragraph 3.E., Compliance, of CFM Service Bulletin (SB) 
LEAP-1A-72-00-0492-01A-930A-D, Issue 001-00, dated April 6, 2023 
(CFM SB LEAP-1A-72-00-0492-01A-930A-D, Issue 001-00), or at the next 
HPT rotor module exposure, whichever occurs first after the 
effective date of this AD, remove the affected HPT rotor interstage 
seal from service and replace it with a part eligible for 
installation.

(h) Definitions

    (1) For the purpose of this AD, an ``affected HPT rotor 
interstage seal'' is any HPT rotor interstage seal having part 
number 2466M68P02 and a serial number listed in Table 1 of paragraph 
3.E., Compliance, of CFM SB LEAP-1A-72-00-0492-01A-930A-D, Issue 
001-00.
    (2) For the purpose of this AD, a ``part eligible for 
installation'' is any HPT rotor interstage seal having a serial 
number that is not listed in Table 1 of paragraph 3.E., Compliance, 
of CFM SB LEAP-1A-72-00-0492-01A-930A-D, Issue 001-00.
    (3) For the purpose of this AD, an ``HPT rotor module exposure'' 
is an engine shop visit during which the HPT rotor assembly is fully 
removed from the engine core.

(i) Alternative Methods of Compliance (AMOCs)

    (1) 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 local 
Flight Standards District Office, as appropriate. If sending 
information directly to the manager of the AIR-520 Continued 
Operational Safety Branch, send it to the attention of the person 
identified in paragraph (j) of this AD and email to [email protected].
    (2) Before using any approved AMOC, notify your appropriate 
principal inspector, or lacking a principal inspector, the manager 
of the local flight standards district office/certificate holding 
district office.

(j) Additional Information

    For more information about this AD, contact Mehdi Lamnyi, 
Aviation Safety Engineer, FAA, 2200 South 216th Street, Des Moines, 
WA 98198; phone: (781) 238-7743; email: [email protected].

(k) Material Incorporated by Reference

    (1) The Director of the Federal Register approved the 
incorporation by reference (IBR) of the service information listed 
in this paragraph under 5 U.S.C. 552(a) and 1 CFR part 51.
    (2) You must use this service information as applicable to do 
the actions required by this AD, unless the AD specifies otherwise.
    (i) CFM International, S.A. Service Bulletin LEAP-1A-72-00-0492-
01A-930A-D, Issue 001-00, dated April 6, 2023.
    (ii) [Reserved]
    (3) For service information, contact CFM International, S.A., GE 
Aviation Fleet Support, 1 Neumann Way, M/D Room 285, Cincinnati, OH 
45215; phone: (877) 432-3272; email: [email protected].
    (4) You may view this service information at FAA, Airworthiness 
Products Section, Operational Safety Branch, 1200 District Avenue, 
Burlington, MA 01803. For information on the availability of this 
material at the FAA, call (817) 222-5110.
    (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 March 27, 2024.
Victor Wicklund,
Deputy Director, Compliance & Airworthiness Division, Aircraft 
Certification Service.
[FR Doc. 2024-09564 Filed 5-3-24; 8:45 am]
BILLING CODE 4910-13-P