[Federal Register Volume 89, Number 145 (Monday, July 29, 2024)]
[Proposed Rules]
[Pages 60838-60841]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2024-16473]
-----------------------------------------------------------------------
DEPARTMENT OF TRANSPORTATION
Federal Aviation Administration
14 CFR Part 39
[Docket No. FAA-2024-1898; Project Identifier AD-2023-01013-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 adopt a new airworthiness directive (AD)
for certain CFM International, S.A. (CFM) Model LEAP-1B engines. This
proposed AD was prompted by a report of a quality escape involving
certain high-pressure compressor (HPC) stage 2 seals manufactured
without detailed finish machining, which could result in deeper rubs
and mechanical damage to the seal teeth of the stage 3-4 compressor
rotor blisk (stage 3-4 blisk) of the mating compressor rotor during
initial operation. This proposed AD would require a visual inspection
of the HPC stage 2 seal, a visual inspection of the forward arm seal
teeth of the stage 3-4 blisk, an eddy current inspection (ECI) of the
forward arm seal teeth of the stage 3-4 blisk, and replacement of the
HPC stage 2 seal and the stage 3-4 blisk, if necessary. 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
12, 2024.
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-2024-1898; 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
[[Page 60839]]
received, and other information. The street address for Docket
Operations is listed above.
Material Incorporated by Reference:
For CFM material identified in this proposed AD, 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 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: 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 to an address listed
under the ADDRESSES section. Include ``Docket No. FAA-2024-1898;
Project Identifier AD-2023-01013-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 was notified by the manufacturer of a quality escape
involving certain HPC stage 2 seals installed on certain CFM Model
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) engines. The suspect HPC stage 2 seals were
manufactured without detailed finish machining, which could result in
deeper rubs and mechanical damage to the seal teeth of the stage 3-4
blisk of the mating compressor rotor during initial operation, which
could lead to failure of the stage 3-4 blisk. This condition, if not
addressed, could result in uncontained part release, damage to the
engine, and damage to the aircraft.
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.
Related Material Under 1 CFR Part 51
The FAA reviewed CFM International, S.A. Service Bulletin LEAP-1B-
72-00-0394-01A-930A-D, Issue 002-00, dated January 23, 2024, which
specifies procedures for an on-wing borescope inspection (BSI) of the
honeycomb structure of the affected stage 2 seals and rotating seal
teeth coating condition and provides instructions for determining the
serviceability of affected components that fail the BSI. This material
also specifies procedures for an in-shop visual inspection of the HPC
stage 2 seal and the forward arm seal teeth of the stage 3-4 blisk, an
ECI of the forward arm seal teeth of the stage 3-4 blisk, and
replacement of the HPC stage 2 seal and the stage 3-4 blisk. 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 HPC stage
2 seal and the forward arm seal teeth of the stage 3-4 blisk, an ECI of
the forward arm seal teeth of the stage 3-4 blisk, and replacement of
the HPC stage 2 seal and the stage 3-4 blisk, if necessary.
Costs of Compliance
The FAA estimates that this AD, if adopted as proposed, would
affect 31 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
----------------------------------------------------------------------------------------------------------------
Visual inspection of HPC stage 2 seal. 1 work-hour x $85 per $0 $85 $2,635
hour = $85.
Visual inspection of stage 3-4 blisk.. 1 work-hour x $85 per 0 85 2,635
hour = $85.
ECI of stage 3-4 blisk................ 4 work-hours x $85 per 0 340 10,540
hour = $340.
----------------------------------------------------------------------------------------------------------------
The FAA estimates the following costs to do any necessary
replacements 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:
[[Page 60840]]
On-Condition Costs
----------------------------------------------------------------------------------------------------------------
Cost per
Action Labor cost Parts cost product
----------------------------------------------------------------------------------------------------------------
Replacement of HPC stage 2 seal............... 8 work-hours x $85 per hour = $55,312 $55,992
$680.
Replacement of stage 3-4 blisk................ 8 work-hours x $85 per hour = 518,500 519,180
$680.
----------------------------------------------------------------------------------------------------------------
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 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-2024-1898; Project
Identifier AD-2023-01013-E.
(a) Comments Due Date
The FAA must receive comments on this airworthiness directive
(AD) by September 12, 2024.
(b) Affected ADs
None.
(c) Applicability
This AD applies to CFM International, S.A. (CFM) Model LEAP-
1B21, LEAP-1B23, LEAP-1B25, LEAP-1B27, LEAP-1B28, LEAP-1B28B1, LEAP-
1B28B2, LEAP-1B28B2C, LEAP-1B28B3, LEAP-1B28BBJ1, and LEAP-1B28BBJ2
engines having an engine serial number (ESN) identified in Table 1
to paragraph (c) of this AD.
Table 1 to Paragraph (c)--Applicable ESNs
----------------------------------------------------------------------------------------------------------------
ESN ESN ESN ESN ESN
----------------------------------------------------------------------------------------------------------------
60A635 60A647 60A662 60A678 60A691
60A639 60A650 60A663 60A679 60A696
60A642 60A653 60A669 60A682 60A702
60A643 60A655 60A670 60A686 ....................
60A644 60A656 60A671 60A687 ....................
60A645 60A660 60A673 60A689 ....................
60A646 60A661 60A676 60A690 ....................
----------------------------------------------------------------------------------------------------------------
(d) Subject
Joint Aircraft System Component (JASC) Code 7230, Turbine Engine
Compressor Section.
(e) Unsafe Condition
This AD was prompted by a report of a quality escape involving
certain high-pressure compressor (HPC) stage 2 seals manufactured
without detailed finish machining, which could result in deeper rubs
and mechanical damage to the seal teeth of the stage 3-4 compressor
rotor blisk (stage 3-4 blisk) of the mating compressor rotor during
initial operation. The FAA is issuing this AD to prevent uncontained
failure of the stage 3-4 blisk. The unsafe condition, if not
addressed, could result in uncontained part release, damage to the
engine, and damage to the aircraft.
(f) Compliance
Comply with this AD within the compliance times specified,
unless already done.
(g) Required Actions
(1) Before accumulating 2,900 cycles since new (CSN) or within
10 flight cycles after the effective date of this AD, whichever
occurs later, perform the following:
(i) A visual inspection of the HPC stage 2 seal in accordance
with the Accomplishment Instructions, paragraph 5.B.(3) of CFM
Service Bulletin (SB) LEAP-1B-72-00-0394-01A-930A-D, Issue 002-00,
dated January 23, 2024 (CFM SB LEAP-1B-72-00-0394-01A-930A-D, Issue
002-00).
(ii) A visual inspection of the forward arm seal teeth of the
stage 3-4 blisk in accordance with the Accomplishment Instructions,
paragraph 5.B.(4) of CFM SB LEAP-1B-72-00-0394-01A-930A-D, Issue
002-00.
(iii) An eddy current inspection of the forward arm seal teeth
of the stage 3-4 blisk in accordance with the Accomplishment
Instructions, paragraph 5.B.(5) of CFM SB LEAP-1B-72-00-0394-01A-
930A-D, Issue 002-00.
(2) If, during the inspection required by paragraph (g)(1)(i) of
this AD, any of the HPC stage 2 seal segments fail to meet the
serviceability criteria specified in the Accomplishment
Instructions, paragraph
[[Page 60841]]
5.B.(3) of CFM SB LEAP-1B-72-00-0394-01A-930A-D, Issue 002-00,
before further flight, remove the unserviceable HPC stage 2 seal
segments from service.
(3) If, during the inspections required by paragraphs (g)(1)(ii)
and (iii) of this AD, the stage 3-4 blisk fails to meet the
serviceability criteria specified in the Accomplishment
Instructions, paragraph 5.B.(6) of CFM SB LEAP-1B-72-00-0394-01A-
930A-D, Issue 002-00, before further flight:
(i) Remove the stage 3-4 blisk from service;
(ii) Remove all four HPC stage 2 seal segments from service; and
(iii) Replace the stage 3-4 blisk in accordance with the
Accomplishment Instructions, paragraph 5.B.(7)(a) of CFM SB LEAP-1B-
72-00-0394-01A-930A-D, Issue 002-00.
(4) If, during the actions required by paragraphs (g)(2) and (3)
of this AD, the HPC stage 2 seal is removed, before further flight,
replace the HPC stage 2 seal in accordance with the Accomplishment
Instructions, paragraph 5.B.(7)(b) of CFM SB LEAP-1B-72-00-0394-01A-
930A-D, Issue 002-00.
(h) 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 (i) 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.
(i) 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].
(j) 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 International, S.A. Service Bulletin LEAP-1B-72-00-0394-
01A-930A-D, Issue 002-00, dated January 23, 2024.
(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) 432-3272; email:
[email protected].
(4) You may view this material 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/ibr-locations or email [email protected].
Issued on July 23, 2024.
Peter A. White,
Deputy Director, Integrated Certificate Management Division, Aircraft
Certification Service.
[FR Doc. 2024-16473 Filed 7-26-24; 8:45 am]
BILLING CODE 4910-13-P