[Federal Register Volume 90, Number 113 (Friday, June 13, 2025)]
[Proposed Rules]
[Pages 25002-25004]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2025-10764]
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DEPARTMENT OF TRANSPORTATION
Federal Aviation Administration
14 CFR Part 39
[Docket No. FAA-2025-0926; Project Identifier AD-2025-00200-E]
RIN 2120-AA64
Airworthiness Directives; International Aero Engines AG 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 certain International Aero Engines AG (IAE AG) Model V2522-A5,
V2524-A5, V2525-D5, V2527-A5, V2527E-A5, V2527M-A5, V2528-D5, V2530-A5,
V2531-E5, and V2533-A5 engines. This proposed AD was prompted by a
manufacturer investigation that revealed a quality escape following
angled ultrasonic inspections (AUSIs) performed on certain high-
pressure turbine (HPT) 1st-stage hubs and HPT 2nd-stage hubs. This
proposed AD would require removal and replacement of certain HPT 1st-
stage hubs and HPT 2nd-stage hubs. 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 July 28,
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-2025-0926; 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: Carol Nguyen, Aviation Safety
Engineer, FAA, 2200 South 216th Street, Des Moines, WA 98198; phone:
(781) 238-7655; 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-2025-0926;
Project Identifier AD-2025-00200-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 Carol
Nguyen, 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.
[[Page 25003]]
Background
The FAA received a report of a quality escape on HPT 1st-stage hubs
and HPT 2nd-stage hubs that had AUSIs performed at production and are
installed on certain IAE AG Model V2522-A5, V2524-A5, V2525-D5, V2527-
A5, V2527E-A5, V2527M-A5, V2528-D5, V2530-A5, V2531-E5, and V2533-A5
engines. A manufacturer investigation of these AUSIs revealed that the
quality escape resulted from the misinterpretation of a rejection
criteria for the AUSIs performed on affected HPT 1st-stage hubs and HPT
2nd-stage hubs. This condition, if not addressed, could result in an
uncontained hub failure, release of high-energy debris, damage to the
engine, damage to the airplane, and loss of the airplane.
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 require removal and replacement of certain
HPT 1st-stage hubs and HPT 2nd-stage hubs.
Costs of Compliance
The FAA estimates that this AD, if adopted as proposed, would
affect two engines of U.S. registry. The FAA estimates that two engines
would need replacement of the HPT 1st-stage hub and no engines would
need replacement of the HPT 2nd-stage hub.
The FAA estimates the following costs to comply with this proposed
AD:
Estimated Costs
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Cost per Cost on U.S.
Action Labor cost Parts cost product operators
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Replace HPT 1st-stage hub.............. 100 work-hours x $85 per hour = $460,000 $468,500 $937,000
$8,500.
Replace HPT 2nd-stage hub.............. 100 work-hours x $85 per hour = 360,000 368,500 0
$8,500.
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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:
International Aero Engines AG: Docket No. FAA-2025-0926; Project
Identifier AD-2025-00200-E.
(a) Comments Due Date
The FAA must receive comments on this airworthiness directive
(AD) by July 28, 2025.
(b) Affected ADs
None.
(c) Applicability
This AD applies to International Aero Engines AG (IAE AG) Model
V2522-A5, V2524-A5, V2525-D5, V2527-A5, V2527E-A5, V2527M-A5, V2528-
D5, V2530-A5, V2531-E5, and V2533-A5 engines.
(d) Subject
Joint Aircraft System Component (JASC) Code 7250, Turbine
Section.
(e) Unsafe Condition
This AD was prompted by a manufacturer investigation that
revealed a quality escape following angled ultrasonic inspections
performed on certain high-pressure turbine (HPT) 1st-stage hubs and
HPT 2nd-stage hubs. The FAA is issuing this AD to prevent failure of
the HPT 1st-stage hub and HPT 2nd-stage hub. The unsafe condition,
if not addressed, could result in an uncontained hub failure,
release of high-energy debris, damage to the engine, damage to the
airplane, and loss of the airplane.
(f) Compliance
Comply with this AD within the compliance times specified,
unless already done.
(g) Required Actions
For engines with an installed part, part number (P/N) and serial
number (S/N) identified in table 1 to paragraph (g) of this AD, at
the next engine shop visit after the effective date of this AD
before exceeding the applicable removal cycle limit listed in table
1 to paragraph (g) of this AD or within 100 flight cycles from the
effective date of this AD, whichever occurs later, remove the
affected part from service and replace with a part eligible for
installation.
[[Page 25004]]
Table 1 to Paragraph (g)--Affected HPT 1st Stage and HPT 2nd Stage Hubs
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Removal cycle limit
Part P/N S/N (cycles since new)
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HPT 1st-stage hub........................................ 2A5001 PKLBSK9287 100
HPT 1st-stage hub........................................ 2A5001 PKLBSS9200 4,800
HPT 1st-stage hub........................................ 2A5001 PKLBST5011 5,500
HPT 1st-stage hub........................................ 2A5001 PKLBST7489 6,200
HPT 2nd-stage hub........................................ 2A4802 PKLBST5005 4,000
HPT 2nd-stage hub........................................ 2A4802 PKLBSS9840 3,900
HPT 2nd-stage hub........................................ 2A4802 PKLBSS0301 5,000
HPT 2nd-stage hub........................................ 2A4802 PKLBSR2100 6,000
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(h) Installation Prohibition
After the effective date of this AD, do not install an HPT 1st-
stage hub or HPT 2nd-stage hub that has a P/N and S/N listed in
table 1 to paragraph (g) of this AD in any engine.
(i) Definitions
For the purpose of this AD:
(1) A ``part eligible for installation'' is an HPT 1st-stage hub
or HPT 2nd-stage hub having a P/N and S/N that is not listed in
table 1 to paragraph (g) of this AD.
(2) An ``engine shop visit'' is the induction of an engine into
the shop for maintenance involving the separation of any major
mating engine flanges, H-P, except for the following situations,
which do not constitute an engine shop visit:
(i) Separation of engine flanges solely for the purposes of
transportation without subsequent engine maintenance.
(ii) Engine removal for the purpose of performing field
maintenance activities at a maintenance facility in lieu of
performing them on-wing.
(j) 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 (k) 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.
(k) Additional Information
For more information about this AD, contact Carol Nguyen,
Aviation Safety Engineer, FAA, 2200 South 216th Street, Des Moines,
WA 98198; phone: (781) 238-7655; email: [email protected].
(l) Material Incorporated by Reference
None.
Issued on June 9, 2025.
Lona C. Saccomando,
Acting Deputy Director, Integrated Certificate Management Division,
Aircraft Certification Service.
[FR Doc. 2025-10764 Filed 6-12-25; 8:45 am]
BILLING CODE 4910-13-P