Document ID: FAA-2022-0515-0006
Agency: faa
Document Type: Rule
Title: Airworthiness Directives: CFM International, S.A. Turbofan Engines
Posted Date: 2022-09-15T04:00Z

[Federal Register Volume 87, Number 178 (Thursday, September 15, 2022)]
[Rules and Regulations]
[Pages 56569-56571]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2022-19946]

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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2022-0515; Project Identifier AD-2022-00287-E; 
Amendment 39-22140; AD 2022-17-02]
RIN 2120-AA64

Airworthiness Directives; CFM International, S.A. Turbofan 
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 
certain CFM International, S.A. (CFM) LEAP-1B model turbofan engines. 
This AD was prompted by multiple commanded in-flight shutdowns (IFSDs) 
due to inner radial drive shaft (RDS) failure. This AD requires initial 
and repetitive inspections of the transfer gearbox (TGB) scavenge 
screens and, depending on the results of the inspections, replacement 
or rework of the affected inner RDS. As a mandatory terminating action 
to the initial and repetitive inspections of the TGB scavenge screens, 
this AD requires replacement or rework of the affected inner RDS. This 
AD also prohibits the installation of an engine with an affected inner 
RDS onto an airplane that already has one engine with an affected inner 
RDS installed. The FAA is issuing this AD to address the unsafe 
condition on these products.

DATES: This AD is effective October 20, 2022.
    The Director of the Federal Register approved the incorporation by 
reference of certain publications listed in this AD as of October 20, 
2022.

ADDRESSES: For service information identified in this final rule, 
contact CFM International, S.A., Aviation Operations Center, 1 Neumann 
Way, M/D Room 285, Cincinnati, OH 45125; 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 www.regulations.gov by searching for and locating 
Docket No. FAA-2022-0515.

Examining the AD Docket

    You may examine the AD docket at www.regulations.gov by searching 
for and locating Docket No. FAA-2022-0515; 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.

FOR FURTHER INFORMATION CONTACT: Mehdi Lamnyi, Aviation Safety 
Engineer, ECO Branch, FAA, 1200 District Avenue, Burlington, MA 01803; 
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 certain CFM LEAP-1B21, 
LEAP-1B23, LEAP-1B25, LEAP-1B27, LEAP-1B28, LEAP-1B28B1, LEAP-1B28B2, 
LEAP-1B28B2C, LEAP-1B28B3, LEAP-1B28BBJ1, and LEAP-1B28BBJ2 (LEAP-1B) 
model turbofan engines. The NPRM published in the Federal Register on 
June 06, 2022 (87 FR 34221). The NPRM was prompted by reports of 
multiple IFSDs on CFM LEAP-1B model turbofan engines beginning in 
August 2018. The manufacturer's investigations determined that some of 
these IFSD events were the result of inadequate oil flow to the RDS 
bearing, which caused the RDS bearing and RDS bearing cage to fail. The 
FAA issued AD 2019-12-01, Amendment 39-19656 (84 FR 28202, June 18, 
2019), which required initial and repetitive inspections of the TGB 
scavenge screens and, depending on the results of the inspection, 
possible removal of the engine from service.
    After the FAA issued AD 2019-12-01, further investigation by the 
manufacturer identified an additional contributing factor to the RDS 
bearing failures. The manufacturer revised the service information to 
include a repetitive TGB screen inspection until the RDS accumulates 
1,500 flight hours (FHs) since new and borescope inspections of the RDS 
bearing at 1,500 FHs since new and 6,000 FHs since new. The FAA 
superseded AD 2019-12-01 by issuing AD 2020-06-01, Amendment 39-21103 
(85 FR 14413, March 12, 2020), which requires revision to the 
airworthiness limitations section (ALS) of the applicable engine shop 
manual to incorporate the new inspections.
    Since the FAA issued AD 2020-06-01, the FAA received further 
reports of commanded IFSDs due to inner RDS failure. The manufacturer 
initiated an investigation and identified a subpopulation of inner RDS 
susceptible to rivet fatigue failure occurring after the inspection 
thresholds required by the ALS revision in AD 2020-06-01. In the NPRM, 
the FAA proposed to require initial and repetitive inspections of the 
TGB1 and TGB2 scavenge screens and, depending on the results of the 
inspections, replacement or rework of the affected inner RDS. As a 
mandatory terminating action to the initial and repetitive inspections 
of the TGB1 and TGB2 scavenge screens, the FAA proposed to require 
replacement or rework of the affected inner RDS. The FAA also proposed 
prohibiting the installation of an engine with an affected inner RDS 
onto an airplane that already has one engine with an affected inner RDS 
installed. The FAA is issuing this AD to address the unsafe condition 
on these products.

Discussion of Final Airworthiness Directive

Comments

    The FAA received comments from three commenters. Commenters 
included The Boeing Company, Air Line Pilots Association, 
International, and United Airlines. All commenters supported the NPRM 
without change.

Conclusion

    The FAA reviewed the relevant data, considered the comments 
received, and determined that air safety requires adopting the 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 (SB) LEAP-1B-72-00-0258-01A-
930A-C, Issue 002, dated September 15, 2020. This service

[[Page 56570]]

information specifies procedures for replacement or rework of the inner 
RDS. The FAA also reviewed CFM SB LEAP-1B-72-00-0365-01A-930A-D, Issue 
003-00, dated April 26, 2022. This service information identifies the 
affected serial numbers of the inner RDS susceptible to rivet fatigue 
failure and specifies procedures for performing inspections of TGB1 and 
TGB2 scavenge screens. This service information also specifies 
procedures for accomplishing applicable corrective actions if metallic 
particles are found. 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 ADDRESSES.

Costs of Compliance

    The FAA estimates that this AD affects 34 engines installed on 
airplanes 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
----------------------------------------------------------------------------------------------------------------
Inspect TGB1 and TGB 2 scavenge       1 work-hour x $85 per                $0              $85           $2,890
 screens.                              hour = $85.
----------------------------------------------------------------------------------------------------------------

    For either replacement or rework of the inner RDS, depending on the 
option selected by the operator to comply with this AD, the FAA 
estimates the following costs:

----------------------------------------------------------------------------------------------------------------
                                                                                                     Cost per
                    Action                                 Labor cost               Parts cost        product
----------------------------------------------------------------------------------------------------------------
Replace inner RDS.............................  600 work-hours x $85 per hour =          $60,000        $111,000
                                                 $51,000.
Rework inner RDS..............................  600 work-hours x $85 per hour =           54,000         105,000
                                                 $51,000.
----------------------------------------------------------------------------------------------------------------

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:

2022-17-02 CFM International, S.A.: Amendment 39-22140; Docket No. 
FAA-2022-0515; Project Identifier AD-2022-00287-E.

(a) Effective Date

    This airworthiness directive (AD) is effective October 20, 2022.

(b) Affected ADs

    None.

(c) Applicability

    This AD applies to CFM International, S.A. (CFM) LEAP-1B21, 
LEAP-1B23, LEAP-1B25, LEAP-1B27, LEAP-1B28, LEAP-1B28B1, LEAP-
1B28B2, LEAP-1B28B2C, LEAP-1B28B3, LEAP-1B28BBJ1, and LEAP-1B28BBJ2 
model turbofan engines with an installed inner radial drive shaft 
(RDS) with a serial number listed in Additional Information, 
paragraph 6.A., Table 1, of CFM Service Bulletin (SB) LEAP-1B-72-00-
0365-01A-930A-D, Issue 003-00, dated April 26, 2022 (CFM SB LEAP-1B-
72-00-0365-01A-930A-D).

(d) Subject

    Joint Aircraft System Component (JASC) Code 7260, Turbine Engine 
Accessory Drive.

(e) Unsafe Condition

    This AD was prompted by multiple commanded in-flight shutdowns 
(IFSDs) due to inner RDS failure. The FAA is issuing this AD to 
prevent failure of the inner RDS and subsequent IFSDs. The unsafe 
condition, if not addressed, could result in failure of one or more 
engines, loss of thrust control, and loss of the airplane.

(f) Compliance

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

(g) Required Actions

    (1) Before exceeding 50 flight hours (FHs) after the effective 
date of this AD, and thereafter at intervals not to exceed 50 FHs 
from the previous inspection, inspect the transfer gearbox (TGB) 
TGB1 and TGB2 scavenge screens in accordance with the Accomplishment 
Instructions, paragraph 5.A.(1), of CFM SB LEAP-1B-72-00-0365-01A-
930A-D.

[[Page 56571]]

    (2) If, during any inspection required by paragraph (g)(1) of 
this AD, any metallic particles are found, before further flight, 
perform the actions in the Accomplishment Instructions, paragraphs 
5.A.(2) and (3), of CFM SB LEAP-1B-72-00-0365-01A-930A-D. Where 
paragraph 5.A.(3)(b) of CFM SB LEAP-1B-72-00-0365-01A-930A-D 
specifies to remove the engine, this AD instead requires replacement 
or rework of the inner RDS in accordance with the Accomplishment 
Instructions, paragraph 5.A., of CFM SB LEAP-1B-72-00-0258-01A-930A-
C Issue 002, dated September 15, 2020 (CFM SB LEAP-1B-72-00-0258-
01A-930A-C).

(h) Mandatory Terminating Action

    As a mandatory terminating action to the initial and repetitive 
inspections of the TGB1 and TGB2 scavenge screens required by 
paragraph (g)(1) of this AD, at the next piece-part exposure after 
the effective date of this AD, replace or rework the inner RDS in 
accordance with the Accomplishment Instructions, paragraph 5.A., of 
CFM SB LEAP-1B-72-00-0258-01A-930A-C.

(i) Installation Prohibition

    After the effective date of this AD, do not install an engine 
with an affected inner RDS onto an airplane that already has one 
engine with an affected inner RDS installed.

(j) Definitions

    For the purpose of this AD, ``piece-part exposure'' is when the 
fan frame shroud is separated from the fan hub.

(k) Alternative Methods of Compliance (AMOCs)

    (1) The Manager, ECO 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 
certification office, send it to the attention of the person 
identified in paragraph (l) 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.

(l) Related Information

    For more information about this AD, contact Mehdi Lamnyi, 
Aviation Safety Engineer, ECO Branch, FAA, 1200 District Avenue, 
Burlington, MA 01803; phone: (781) 238-7743; email: 
[email protected].

(m) 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-1B-72-00-0258-
01A-930A-C, Issue 002, dated September 15, 2020.
    (ii) CFM International, S.A. Service Bulletin LEAP-1B-72-00-
0365-01A-930A-D, Issue 003-00, dated April 26, 2022.
    (3) For service information identified in this AD, contact CFM 
International, S.A., Aviation Operations Center, 1 Neumann Way, M/D 
Room 285, Cincinnati, OH 45125; 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 service information that is incorporated 
by reference at the National Archives and Records Administration 
(NARA). For information on the availability of this material at 
NARA, email: [email protected], or go to: www.archives.gov/federal-register/cfr/ibr-locations.html.

    Issued on August 2, 2022.
Christina Underwood,
Acting Director, Compliance & Airworthiness Division, Aircraft 
Certification Service.
[FR Doc. 2022-19946 Filed 9-14-22; 8:45 am]
BILLING CODE 4910-13-P