Airworthiness Directives; CFM International, S.A. Engines

Issuing agencies

Abstract

The FAA proposes to adopt a new airworthiness directive (AD) for all CFM International, S.A. (CFM) Model CFM56-7B engines. This proposed AD was prompted by an event involving a CFM Model CFM56-7B26/3 engine where a fan blade separated and resulted in an engine in-flight shutdown (IFSD) with debris penetrating the fuselage, which caused a loss of pressurization and prompted an emergency descent. This proposed AD would require a visual inspection of the fan blades for findings considered not serviceable and, depending on the results of the inspection, replacement with a serviceable part and additional fan blade inspections. This proposed AD would also require sending the inspection results to CFM if any finding considered not serviceable is found. The FAA is proposing this AD to address the unsafe condition on these products.

Full Text

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<title>Federal Register, Volume 91 Issue 206 (Tuesday, October 27, 2026)</title>
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[Federal Register Volume 91, Number 206 (Tuesday, October 27, 2026)]
[Proposed Rules]
[Pages 67532-67535]
From the Federal Register Online via the Government Publishing Office [<a href="http://www.gpo.gov">www.gpo.gov</a>]
[FR Doc No: 2026-21852]


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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2026-11817; Project Identifier AD-2026-01020-E]
RIN 2120-AA64


Airworthiness Directives; CFM International, S.A. Engines

AGENCY: Federal Aviation Administration (FAA), DOT.

ACTION: Notice of proposed rulemaking (NPRM).

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SUMMARY: The FAA proposes to adopt a new airworthiness directive (AD) 
for all CFM International, S.A. (CFM) Model CFM56-7B engines. This 
proposed AD was prompted by an event involving a CFM Model CFM56-7B26/3 
engine where a fan blade separated and resulted in an engine in-flight 
shutdown (IFSD) with debris penetrating the fuselage, which caused a 
loss of pressurization and prompted an emergency descent. This proposed 
AD would require a visual inspection of the fan blades for findings 
considered not serviceable and, depending on the results of the 
inspection, replacement with a serviceable part and additional fan 
blade inspections. This proposed AD would also require sending the 
inspection results to CFM if any finding considered not serviceable is 
found. 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 November 
27, 2026.

ADDRESSES: You may send comments, using the procedures found in 14 CFR 
11.43 and 11.45, by any of the following methods:
    <bullet> Federal eRulemaking Portal: Go to <a href="http://regulations.gov">regulations.gov</a>. Follow 
the instructions for submitting comments.
    <bullet> Fax: (202) 493-2251.
    <bullet> 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.
    <bullet> 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 <a href="http://regulations.gov">regulations.gov</a> under 
Docket No. FAA-2026-11817; 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.
    Material Incorporated by Reference:
    <bullet> For CFM material identified in this proposed AD, contact 
CFM, GE Aviation Fleet Support, 1 Neumann Way, M/D Room 285, 
Cincinnati, OH 45215; phone: (877) 432-3272; email: 
<a href="/cdn-cgi/l/email-protection#a9c8dfc0c8ddc0c6c787cfc5ccccdddadcd9d9c6dbdde9cecc87cac6c4"><span class="__cf_email__" data-cfemail="3756415e56435e585919515b525243444247475845437750521954585a">[email&#160;protected]</span></a>.
    <bullet> You may view this material 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.

FOR FURTHER INFORMATION CONTACT: Alexei Marqueen, Aviation Safety 
Engineer, FAA, 2200 South 216th Street, Des Moines, WA 98198; phone: 
(781) 238-7178; email: <a href="/cdn-cgi/l/email-protection#30515c554855591e441e5d5142414555555e705651511e575f46"><span class="__cf_email__" data-cfemail="fc9d9099849995d288d2919d8e8d89999992bc9a9d9dd29b938a">[email&#160;protected]</span></a>.

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-2026-11817; 
Project Identifier AD-2026-01020-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 
<a href="http://regulations.gov">regulations.gov</a>, 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 
Alexei Marqueen, 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 received a report that a Boeing 737-800 Model airplane 
powered by CFM56-7B26/3 engines experienced a fan blade separation 
during flight that resulted in an engine IFSD with debris penetrating 
the fuselage, which caused a loss of pressurization and prompted an 
emergency descent. The manufacturer investigation into the root cause 
of the fan blade failure is ongoing, but preliminary investigation 
indicates deformation to the fan blades induced a localized vibratory 
response in the failed blade. This condition, if not addressed, could 
result in debris penetrating the fuselage and cause a loss of 
pressurization and prompt an emergency descent.
    On April 17, 2018, a Southwest Airlines flight experienced a CFM56-
7B engine failure due to a fractured fan blade that led to the engine 
inlet cowl

[[Page 67533]]

disintegrating and debris penetrating the fuselage. The FAA has 
received no factual information that indicates that the April 17, 2018 
incident on a Southwest Airlines flight is related to the unsafe 
condition addressed by this proposed AD. It is noted here for 
completeness only.
    The FAA is providing a 30-day comment period for this NPRM instead 
of the standard 45-day comment period. This shortened timeframe is 
necessary to align the effective implementation of this safety action 
with the European Union Aviation Safety Agency (EASA), which is the 
Technical Agent for the Member States of the European Union, and in 
consideration of the recent in-service engine event. The FAA has 
determined that a 30-day comment period provides sufficient opportunity 
for public input while ensuring harmonization with EASA.

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.

Material Incorporated by Reference Under 1 CFR Part 51

    The FAA reviewed CFM Service Bulletin CFM56-7B S/B 72-1119, dated 
September 8, 2026, which specifies procedures for visual inspection of 
the fan blades for findings considered not serviceable (cracks, tears, 
tip curls, local distortion on leading edge), and additional 
inspections of adjacent (forward looking aft) fan blades. 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.

Proposed AD Requirements in This NPRM

    This proposed AD would require a visual inspection of the fan 
blades for findings considered not serviceable (cracks, tears, tip 
curls, local distortion on leading edge) and, depending on the results 
of the inspection, replacement with a serviceable part and additional 
fan blade inspections. This proposed AD would also require sending the 
inspection results to CFM if any unserviceable finding is found.

Interim Action

    This AD is considered to be interim action. The inspection reports 
that are required by this AD will enable the manufacturer to obtain 
better insight into the nature, cause, and extent of the fan blade 
failure, and eventually allow the manufacturer to develop final action 
to address the unsafe condition. Once final action has been identified, 
the FAA might consider further rulemaking.

Costs of Compliance

    The FAA estimates that this AD, if adopted as proposed, would 
affect 3,450 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
----------------------------------------------------------------------------------------------------------------
Visually inspect fan blades..............  1 work-hour x $85 per hour            $0          $85        $293,250
                                            = $85.
----------------------------------------------------------------------------------------------------------------

    The FAA estimates the following costs to do any necessary 
replacements and additional inspections that would be required based on 
the results of the proposed inspection. The agency has no way of 
determining the number of engines that might need these replacements 
and additional inspections:

                                               On-Condition Costs
----------------------------------------------------------------------------------------------------------------
                    Action                                Labor cost              Parts cost   Cost per product
----------------------------------------------------------------------------------------------------------------
Remove and replace fan blade.................  1 work-hour x $85 per hour = $85      $51,400             $51,485
Inspect adjacent fan blade...................  2 work-hours x $85 per hour =               0                 170
                                                $170.
Report inspection results....................  1 work-hour x $85 per hour = $85            0                  85
----------------------------------------------------------------------------------------------------------------

Paperwork Reduction Act

    A federal agency may not conduct or sponsor, and a person is not 
required to respond to, nor shall a person be subject to a penalty for 
failure to comply with a collection of information subject to the 
requirements of the Paperwork Reduction Act unless that collection of 
information displays a currently valid OMB Control Number. The OMB 
Control Number for this information collection is 2120-0056. Public 
reporting for this collection of information is estimated to be 
approximately 1 hour per response, including the time for reviewing 
instructions, searching existing data sources, gathering and 
maintaining the data needed, and completing and reviewing the 
collection of information. All responses to this collection of 
information are mandatory. Send comments regarding this burden estimate 
or any other aspect of this collection of information, including 
suggestions for reducing this burden, to: Information Collection 
Clearance Officer, Federal Aviation Administration, 10101 Hillwood 
Parkway, Fort Worth, TX 76177-1524.

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

[[Page 67534]]

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 adding the following new airworthiness 
directive:

CFM International, S.A.: Docket No. FAA-2026-11817; Project 
Identifier AD-2026-01020-E.

(a) Comments Due Date

    The FAA must receive comments on this airworthiness directive 
(AD) by November 27, 2026.

(b) Affected ADs

    None.

(c) Applicability

    This AD applies to all CFM International, S.A. (CFM) Model 
CFM56-7B20, CFM56-7B20/2, CFM56-7B20/3, CFM56-7B20E, CFM56-7B22, 
CFM56-7B22/2, CFM56-7B22/3, CFM56-7B22/3B1, CFM56-7B22/B1, CFM56-
7B22E, CFM56-7B22E/B1, CFM56-7B24, CFM56-7B24/2, CFM56-7B24/3, 
CFM56-7B24/3B1, CFM56-7B24/B1, CFM56-7B24E, CFM56-7B24E/B1, CFM56-
7B26, CFM56-7B26/2, CFM56-7B26/3, CFM56-7B26/3B1, CFM56-7B26/3B2, 
CFM56-7B26/3B2F, CFM56-7B26/3F, CFM56-7B26/B1, CFM56-7B26/B2, CFM56-
7B26E, CFM56-7B26E/B1, CFM56-7B26E/B2, CFM56-7B26E/B2F, CFM56-7B26E/
F, CFM56-7B27, CFM56-7B27/2, CFM56-7B27/3, CFM56-7B27/3B1, CFM56-
7B27/3B1F, CFM56-7B27/3B3, CFM56-7B27/3F, CFM56-7B27/B1, CFM56-7B27/
B3, CFM56-7B27A, CFM56-7B27A/3, CFM56-7B27AE, CFM56-7B27E, CFM56-
7B27E/B1, CFM56-7B27E/B1F, CFM56-7B27E/B3, and CFM56-7B27E/F 
engines.

(d) Subject

    Joint Aircraft System Component (JASC) Code 7230, Turbine Engine 
Compressor Section.

(e) Unsafe Condition

    This AD was prompted by an event involving a CFM Model CFM56-
7B26/3 engine, which experienced a fan blade separation that 
resulted in an in-flight engine shutdown and debris penetrating the 
fuselage, causing a loss of pressurization and prompting an 
emergency descent. The FAA is issuing this AD to prevent failure of 
the fan blade. The unsafe condition, if not addressed, could result 
in debris penetrating the fuselage and cause a loss of 
pressurization and prompt an emergency descent.

(f) Compliance

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

(g) Definition

    For the purpose of this AD, a ``serviceable fan blade'' is a 
new, zero-hour fan blade or a fan blade that has passed the 
inspections required by paragraph (h)(1) of this AD.

(h) Required Actions

    (1) Perform a visual inspection of the fan blades in accordance 
with the Accomplishment Instructions, paragraph 3.C., of CFM Service 
Bulletin (SB) CFM56-7B S/B 72-1119, dated September 8, 2026 (CFM56-
7B S/B 72-1119), as follows:
    (i) For engines installed on aircraft as of the effective date 
of this AD, within 400 flight cycles or within 90 days after the 
effective date of this AD, whichever occurs first.
    (ii) For engines not installed on aircraft as of the effective 
date of this AD, before further flight.
    (2) If any findings considered not serviceable are detected, 
before further flight, do the following:
    (i) Remove the fan blade from service and replace with a 
serviceable fan blade.
    (ii) Perform an inspection of the adjacent clockwise (forward 
looking aft) fan blade for findings considered not serviceable in 
accordance with the Accomplishment Instructions, paragraph 3.D.(2), 
of CFM56-7B S/B 72-1119.
    (iii) If any unserviceable finding is found during the 
inspection required by paragraph (h)(2)(ii) of this AD, before 
further flight, remove the fan blade from service and replace with a 
serviceable fan blade.

(i) Credit for Previous Actions

    This paragraph provides credit for actions required by paragraph 
(h) of this AD, if those actions were performed prior to the 
effective date of this AD using the material identified in, and 
meeting the applicable conditions specified in, paragraphs (i)(1) 
through (3) of this AD.
    (1) Credit is allowed for the actions required by paragraph (h) 
of this AD if an engine shop manual piece-part inspection was 
performed on each fan blade in the set within 100 flight cycles 
prior to the effective date of this AD; or
    (2) Credit is allowed if the actions required by paragraph (h) 
of this AD were performed within 100 flight cycles prior to the 
effective date of this AD using CFM SB CFM56-7B S/B 72-1033, 
Revision 3, dated November 6, 2018; CFM56-7B S/B 72-1033, Revision 
4, dated September 12, 2019; CFM56-7B S/B 72-1033, Revision 5, dated 
July 28, 2026; or CFM56-7B S/B 72-1033, Revision 6, dated August 14, 
2026; or
    (3) Credit is allowed if the actions required by paragraph (h) 
of this AD were performed using CFM SB CFM56-7B S/B 72-1118, dated 
June 1, 2026.

(j) Reporting Requirement

    Report the results of the inspections required by paragraph (h) 
of this AD to CFM within 30 days after the inspection or within 30 
days after the effective date of this AD, whichever occurs later, in 
accordance with the Accomplishment Instructions, paragraph 3.D.(3), 
of CFM56-7B S/B 72-1119.

(k) 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 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 (l)(1) of this AD and email to: <a href="/cdn-cgi/l/email-protection#6e2f23212d2e080f0f40090118"><span class="__cf_email__" data-cfemail="efaea2a0acaf898e8ec1888099">[email&#160;protected]</span></a>. 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.

(l) Additional Information

    (1) For more information about this AD, contact Alexei Marqueen, 
Aviation Safety Engineer, FAA, 2200 South 216th Street, Des Moines, 
WA 98198; phone: (781) 238-7178; email: <a href="/cdn-cgi/l/email-protection#66070a031e030f4812480b071417130303082600070748010910"><span class="__cf_email__" data-cfemail="8dece1e8f5e8e4a3f9a3e0ecfffcf8e8e8e3cdebececa3eae2fb">[email&#160;protected]</span></a>.
    (2) For material identified in this AD that is not incorporated 
by reference, contact CFM International, S.A., GE Aviation Fleet 
Support, 1 Neumann Way, M/D Room 285, Cincinnati, OH 45215; phone: 
(877) 432-3272; email: <a href="/cdn-cgi/l/email-protection#0766716e66736e686929616b626273747277776875734760622964686a"><span class="__cf_email__" data-cfemail="97f6e1fef6e3fef8f9b9f1fbf2f2e3e4e2e7e7f8e5e3d7f0f2b9f4f8fa">[email&#160;protected]</span></a>.

(m) Material Incorporated by Reference

    (1) The Director of the Federal Register approved the 
incorporation by reference (IBR) 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 the AD specifies otherwise.
    (i) CFM Service Bulletin CFM56-7B S/B 72-1119, dated September 
8, 2026.
    (ii) [Reserved]
    (3) For CFM material identified in this AD, contact CFM 
International, S.A., GE Aviation Fleet Support, 1 Neumann Way, M/D 
Room 285, Cincinnati, OH 45215; phone: (877)

[[Page 67535]]

432-3272; email: <a href="/cdn-cgi/l/email-protection#0e6f78676f7a6761602068626b6b7a7d7b7e7e617c7a4e696b206d6163"><span class="__cf_email__" data-cfemail="bedfc8d7dfcad7d1d090d8d2dbdbcacdcbceced1cccafed9db90ddd1d3">[email&#160;protected]</span></a>.
    (4) You may view this material 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.
    (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 <a href="http://www.archives.gov/federal-register/cfr/ibr-locations">www.archives.gov/federal-register/cfr/ibr-locations</a> or email <a href="/cdn-cgi/l/email-protection#e88e9ac681869b988d8b9c818786a886899a89c68f879e"><span class="__cf_email__" data-cfemail="aec8dc80c7c0dddecbcddac7c1c0eec0cfdccf80c9c1d8">[email&#160;protected]</span></a>.

    Issued on October 22, 2026.
Brian Knaup,
Acting Deputy Director, Integrated Certificate Management Division, 
Aircraft Certification Service.
[FR Doc. 2026-21852 Filed 10-26-26; 8:45 am]
BILLING CODE 4910-13-P


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