[Federal Register Volume 90, Number 149 (Wednesday, August 6, 2025)]
[Proposed Rules]
[Pages 37808-37810]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2025-14890]


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Proposed Rules
                                                Federal Register
________________________________________________________________________

This section of the FEDERAL REGISTER contains notices to the public of 
the proposed issuance of rules and regulations. The purpose of these 
notices is to give interested persons an opportunity to participate in 
the rule making prior to the adoption of the final rules.

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Federal Register / Vol. 90, No. 149 / Wednesday, August 6, 2025 / 
Proposed Rules

[[Page 37808]]



DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2025-1725; Project Identifier AD-2025-00583-E]
RIN 2120-AA64


Airworthiness Directives; CFM International, S.A. Engines

AGENCY: Federal Aviation Administration (FAA), DOT.

ACTION: Notice of proposed rulemaking (NPRM).

-----------------------------------------------------------------------

SUMMARY: The FAA proposes to supersede Airworthiness Directive (AD) 
2018-19-16, which applies to all CFM International, S.A. (CFM) Model 
LEAP-1A23, -1A24, -1A24E1, -1A26, -1A26E1, -1A26CJ, -1A29, -1A29CJ, -
1A30, -1A32, -1A33, -1A33B2, and -1A35A engines with certain full 
authority digital engine control (FADEC) and prognostic health 
monitoring (PHM) software installed. AD 2018-19-16 requires removing 
certain FADEC and PHM software and installing versions eligible for 
installation. Since the FAA issued AD 2018-19-16, the manufacturer has 
developed a new pressure subsystem (PSS) with a heater element to 
evaporate potential moisture on the PSS manifold/transducer interface 
and prevent freezing at low temperature. This proposed AD would require 
replacing certain FADEC and PHM software with new versions that are 
eligible for installation, replacement of certain harnesses with newly 
designed harnesses, and replacement of the PSS with a newly designed 
heated PSS. 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 September 
22, 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-2025-1725; 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, any comments received, and other 
information. The street address for Docket Operations is listed above.

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:

Comments Invited

    The FAA invites you to send any written relevant data, views, or 
arguments about this proposal. Send your comments using a method listed 
under the ADDRESSES section. Include ``Docket No. FAA-2025-1725; 
Project Identifier AD-2025-00583-E'' at the beginning of your comments. 
The most helpful comments reference a specific portion of the proposal, 
explain the reason for any recommended change, and include supporting 
data. The FAA will consider all comments received by the closing date 
and may revise 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 Mehdi 
Lamnyi, Aviation Safety Engineer, FAA, 2200 South 216th Street, Des 
Moines, WA 98198. 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 2018-19-16, Amendment 39-19416 (83 FR 50818, 
October 10, 2018) (AD 2018-19-16), for certain CFM Model LEAP-1A23, -
1A24, -1A24E1, -1A26, -1A26E1, -1A26CJ, -1A29, -1A29CJ, -1A30, -1A32, -
1A33, -1A33B2, and -1A35A engines. AD 2018-19-16 was prompted by 
aborted takeoffs after engines did not advance to the desired takeoff 
fan speed due to icing in the pressure sensor line. AD 2018-19-16 
requires removing certain FADEC and PHM software and installing 
versions eligible for installation. The agency issued AD 2018-19-16 to 
prevent icing in the pressure sensor lines and inaccurate pressure 
sensor readings, which could result in failure of one or more engines, 
loss of thrust control, and loss of the airplane.

Actions Since AD 2018-19-16 Was Issued

    The preamble to AD 2018-19-16 specifies that the FAA considers that 
AD ``interim action,'' that the manufacturer was developing a 
modification to address the unsafe condition, and that the FAA might 
consider further rulemaking once the modification is developed, 
approved, and available. Since the FAA issued AD 2018-19-16, the 
manufacturer has developed a new pressure subsystem

[[Page 37809]]

with a heater element to evaporate potential moisture on the PSS 
manifold/transducer interface and prevent freezing at low temperature, 
which would mitigate the unsafe condition specified in AD 2018-19-16. 
The FAA has determined that this modification should be required.

FAA's Determination

    The FAA is issuing this NPRM after determining that the unsafe 
condition described previously is likely to exist or develop on other 
products of the same type design.

Proposed AD Requirements in This NPRM

    This proposed AD would retain none of the requirements of AD 2018-
19-16. This proposed AD would require replacing certain FADEC and PHM 
software with new versions that are eligible for installation, 
replacement of the HJ6A and HJ6B harnesses with newly designed 
harnesses, and replacement of the PSS with a newly designed heated PSS.

Costs of Compliance

    The FAA estimates that this AD, if adopted as proposed, would 
affect 306 engines installed on airplanes of U.S. registry.
    The FAA estimates the following costs to comply with this proposed 
AD:

                                                 Estimated Costs
----------------------------------------------------------------------------------------------------------------
                                                                                       Cost per    Cost on U.S.
                  Action                            Labor cost           Parts cost    product       operators
----------------------------------------------------------------------------------------------------------------
Install electronic engine control          1 work-hour x $85 per hour            $0          $85         $26,010
 software.                                  = $85.
Replace PSS with heated PSS..............  1 work-hours x $85 per hour      185,950      186,035      56,926,710
                                            = $85.
Replace HJ6A and HJ6B harnesses..........  1 work-hour x $85 per hour        57,510       57,595      17,624,070
                                            = $85.
----------------------------------------------------------------------------------------------------------------

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 that the 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 2018-19-16, Amendment 39-19416 (83 
FR 50818, October 10, 2018); and
0
b. Adding the following new airworthiness directive:

CFM International, S.A.: Docket No. FAA-2025-1725; Project 
Identifier AD-2025-00583-E.

(a) Comments Due Date

    The FAA must receive comments on this airworthiness directive 
(AD) by September 22, 2025.

(b) Affected ADs

    This AD replaces AD 2018-19-16, Amendment 39-19416 (83 FR 50818, 
October 10, 2018) (AD 2018-19-16).

(c) Applicability

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

(d) Subject

    Joint Aircraft System Component (JASC) Code 7600, Engine 
Controls.

(e) Unsafe Condition

    This AD was prompted by aborted takeoffs after engines did not 
advance to the desired takeoff fan speed due to icing in the 
pressure sensor line. The FAA is issuing this AD to prevent icing in 
the pressure sensor lines and inaccurate pressure sensor readings. 
The unsafe condition, if not addressed, could result in loss of 
engine thrust control and reduced control of the airplane.

(f) Compliance

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

(g) Required Actions

    At the next engine shop visit after the effective date of this 
AD, do the following actions:
    (1) Install electronic engine control (EEC) full authority 
digital electronic control (FADEC) software having part number (P/N) 
2590M00P13, version L1A0850, or later approved version; and 
prognostic health monitoring (PHM) software having P/N 2784M64P08, 
version PL1A0850, or later approved version.
    Note 1 to paragraph (g)(1): The software release that includes 
EEC FADEC software P/N 2590M00P13, version L1A0850, and PHM software 
P/N 2784M64P08, version PL1A0850, is commonly referred to as 
``FCS8.5.'' Guidance for replacing the EEC FADEC software and PHM 
software may be found in CFM Service Bulletin LEAP-1A-73-00-0050-
01A-930A-D, Issue 001-00, dated January 03, 2024.
    (2) For engines with an installed HJ6A harness having P/N 362-
085-905-0 (significant item number (SIN) 65004), remove the HJ6A 
harness from service and replace with an HJ6A harness having P/N 
362-085-906-0, or later approved P/N.
    (3) For engines with an installed HJ6B harness having P/N 362-
086-004-0 (SIN 65005), remove the HJ6B harness from service and 
replace with an HJ6B harness

[[Page 37810]]

having P/N 362-086-005-0, or later approved P/N.
    (4) For engines with an installed pressure subsystem (PSS) 
having P/N 2474M65P05 (vendor identification number (VIN) 261811055-
0303), remove the PSS from service and replace with a heated PSS 
having P/N 2474M65P08 (VIN 261811055-0410), or later approved P/N.

(h) Definitions

    For the purpose of this AD, an ``engine shop visit'' is the 
induction of the engine into the shop for maintenance involving the 
separation of major mating engine flanges, except for the separation 
of engine flanges solely for the purposes of transportation without 
subsequent engine maintenance.

(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)(1) of this AD. Information may be 
emailed 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

    (1) 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].
    (2) For material identified in this AD that is not incorporated 
by reference, contact CFM, GE Aviation Fleet Support, 1 Neumann Way, 
M/D Room 285, Cincinnati, OH 45215; phone: (877) 432-3272; email: 
[email protected].

(k) Material Incorporated by Reference

    None.

    Issued on July 25, 2025.
Peter A. White,
Deputy Director, Integrated Certificate Management Division, Aircraft 
Certification Service.
[FR Doc. 2025-14890 Filed 8-5-25; 8:45 am]
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