[Federal Register Volume 89, Number 136 (Tuesday, July 16, 2024)]
[Rules and Regulations]
[Pages 57725-57728]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2024-15466]


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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2024-0763; Project Identifier AD-2023-00924-E; 
Amendment 39-22785; AD 2024-14-04]
RIN 2120-AA64


Airworthiness Directives; International Aero Engines, LLC

AGENCY: Federal Aviation Administration (FAA), DOT.

ACTION: Final rule.

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SUMMARY: The FAA is adopting a new airworthiness directive (AD) for all 
International Aero Engines, LLC (IAE LLC) Model PW1122G-JM, PW1124G1-
JM, PW1124G-JM, PW1127G1-JM, PW1127G1A-JM, PW1127G1B-JM, PW1127G-JM, 
PW1127GA-JM, PW1129G-JM, PW1130G-JM, PW1133G-JM, and PW1133GA-JM 
engines. This AD was prompted by an in-flight shutdown (IFSD) caused by 
the fracture of a low-pressure compressor (LPC) 1st-stage integrally 
bladed rotor (IBR-1). This AD requires removal and replacement of 
affected LPC key washers and affected LPC IBR-1 and installation of 
inlet guide vane (IGV) spacers. The FAA is issuing this AD to address 
the unsafe condition on these products.

DATES: This AD is effective August 20, 2024.

ADDRESSES: 
    AD Docket: You may examine the AD docket at regulations.gov under 
Docket No. FAA-2024-0763; 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: Carol Nguyen, Aviation Safety 
Engineer, FAA, 2200 South 216th Street, Des Moines, WA 98198; phone: 
(781) 238-7655; 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 all IAE LLC Model 
PW1122G-JM, PW1124G1-JM, PW1124G-JM, PW1127G1-JM, PW1127G1A-JM, 
PW1127G1B-JM, PW1127G-JM, PW1127GA-JM, PW1129G-JM, PW1130G-JM, PW1133G-
JM, and PW1133GA-JM engines. The NPRM published in the Federal Register 
on March 25, 2024 (89 FR 20551). The NPRM was prompted by an incident 
involving an Airbus Model A320neo airplane powered by IAE LLC Model 
PW1127G-JM engines that experienced an IFSD. A manufacturer 
investigation determined that the IFSD was caused by a fractured LPC 
IBR-1, which resulted from an aerodynamic excitation. The most likely 
cause of the aerodynamic excitation was a misaligned IGV located 
directly upstream of the IBR-1. As a result, Pratt & Whitney (PW) 
redesigned the LPC IGV arm assembly by adding a spacer to provide 
additional torque capability and to prevent a misaligned vane. PW also 
redesigned the IBR-1 to better withstand an aerodynamic excitation from 
a misaligned IGV. In the NPRM, the FAA proposed to require removal and 
replacement of affected LPC key washers and affected LPC IBR-1 and 
installation of LPC IGV spacers. 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 four commenters. The commenters were 
the Air Line Pilots Association, International (ALPA), All Nippon 
Airways CO., LTD. (ANA), Delta Air Lines, Inc (DAL), and Frontier 
Airlines (Frontier). ALPA supported the NPRM without change. The 
following presents the comments received on the NPRM and the FAA's 
response to each comment.

Request To Update Paragraph (g)(1)

    Frontier requested that the FAA update paragraph (g)(1) of the 
proposed AD to read as follows: ``For engines that are pre-PW Service 
Bulletin (SB) PW1000G-C-72-00-0180-00A-930A-D, Issue No. 001, dated 
October 10, 2020 (PW SB PW1000G-C-72-00-0180-00A-

[[Page 57726]]

930A-D) with installed LPC key washers having P/N 5375416, at the next 
engine shop visit after the effective date of this AD, remove the 
affected LPC key washers and replace them with LPC key washers and LPC 
IGV spacers that are eligible for installation.'' Frontier noted that 
tracking installed washers on engines is very difficult since they are 
not tracked parts, and post service bulletin engines have LPC key 
washers and LPT IGV spacers that are eligible for installation.
    The FAA agrees to update paragraph (g)(1) of this AD to include 
reference to engines that have not incorporated PW SB PW1000G-C-72-00-
0180-00A-930A-D.

Request To Update Paragraph (g)(2)

    Frontier requested that the FAA update paragraph (g)(2) of the 
proposed AD to read as follows: ``For engines that are pre-service 
bulletin SB PW1000G-C-72-00-0189-00A-930A-D, with an installed LPC IBR-
1 having PN 5373831, at the next piece-part exposure after effective 
date of this AD, remove the affected LPC IBR-1 and replace with an LPC 
IBR-1 eligible for installation.''
    The FAA disagrees with the request because the LPC IBR-1 is a 
tracked life-limited part, so adding qualifying language for ``pre-PW 
SB PW1000G-C-72-00-0189-00A-930A-D'' engines is unnecessary. The FAA 
did not change this AD as a result of this comment.

Request To Add ``Credit for Previous Actions'' Paragraph

    DAL requested that the FAA add a ``Credit for Previous Actions'' 
paragraph to the proposed AD to allow credit for the actions required 
by paragraph (g)(1) if PW SB PW1000G-C-72-00-0180-00A-930A-D was 
previously accomplished. ANA also requested that accomplishment of PW 
SB PW1000G-C-72-00-0180-00A-930A-D be accepted as credit for paragraph 
(g)(1) of the proposed AD, and accomplishment of PW SB PW1000G-C-72-00-
0189-00A-930A, Issue 001, dated January 26, 2022, PW SB PW1000G-C-72-
00-0189-00A-930A, Issue 002, dated March 15, 2022, and PW SB PW1000G-C-
72-00-0189-00A-930A, Issue 003, dated November 28, 2022, be accepted as 
credit for paragraph (g)(2) of the proposed AD if these actions were 
performed before the effective date of the proposed AD. DAL noted that 
because the proposed AD does not provide credit for installing the 
post-SB spacers and washers, operators must physically verify that all 
61 spacers are present and all 61 washers are post-SB on all engines, 
regardless of whether or not the engine records show accomplishment of 
PW SB PW1000G-C-72-00-0180-00A-930A-D. DAL also noted that this is a 
very manual, time-intensive task that should be avoided considering PW 
SB PW1000G-C-72-00-0180-00A-930A-D installs key washers P/N 5375416 and 
LPC spacers P/N 5375433, and those parts comply with the ``part 
eligible for installation'' definitions listed in paragraphs (h)(3) and 
(h)(4) of the proposed AD.
    The FAA disagrees with the request to add a ``Credit for Previous 
Actions'' paragraph to this AD. This AD references affected engines 
with specific P/Ns installed in paragraph (g) of this AD, and if the 
service bulletins related to this AD have already been performed on the 
engine, then the affected P/Ns are no longer installed and the AD is no 
longer applicable to those engines. Therefore, previous credit is not 
necessary because the engine no longer has an affected P/N installed. 
The FAA notes that paragraph (g)(1) of this AD has been changed to 
reference PW SB PW1000G-C-72-00-0180-00A-930A-D and to reduce the 
burden on operators. The FAA did not change this AD as a result of this 
comment.

Request To Clarify Meaning of ``At the Next Piece-Part Exposure''

    ANA requested that the FAA clarify the meaning of ``at the next 
piece-part exposure'' in paragraph (g)(2) of the proposed AD. ANA asks 
if LPC IBR-1 is already separated from the LPC module and assembly has 
already begun by the effective date of this AD, should the requirement 
of paragraph (g)(2) not be performed in this shop visit? ANA also 
wondered about the same scenario if the assembly had not begun by the 
effective date of this AD.
    To clarify, the FAA's meaning of ``at the next piece-part 
exposure'' covers both cases. Paragraph (h)(2) of this AD defines a 
``piece-part exposure'' as when the LPC IBR-1 is separated from the LPC 
module. The FAA considers the ``next'' exposure to include any 
separation of the LPC IBR-1 from the LPC module after the effective 
date of this AD. If the LPC IBR-1 is assembled into the module on the 
effective date of this AD, then it is not a ``piece-part exposure.'' If 
the LPC IBR-1 is separated from the LPC module after the effective date 
of the AD, then paragraph (g)(2) of this AD will need to be performed 
because it will meet the definition of ``piece-part exposure''. The FAA 
is not concerned if the assembly of the LPC module has started or not.
    The FAA did not change this AD as a result of this comment.

Request To Clarify ``Major Mating Engine Flanges''

    ANA requested that the FAA clarify if ``major mating engine 
flanges'' referenced in paragraph (h)(1) of the proposed AD are 
considered as flanges E through P.
    To clarify, the FAA considers the major mating engine flanges 
referenced in paragraph (h)(1) of this AD as flanges E through P, 
inclusive. The FAA did not change this AD as a result of this comment.

Request To Clarify ``Induction of an Engine''

    ANA requested that the FAA clarify the meaning of ``induction of an 
engine'' in paragraph (h)(1) of the proposed AD. ANA asked if an engine 
is already in-shop for maintenance involving the separation of pairs of 
major mating engine flanges at the effective date of this AD, does 
paragraph (g)(1) need to be performed in this shop visit?
    To clarify, the FAA's meaning of ``induction of an engine'' when 
using the example provided by ANA is: ``if the engine was already at an 
engine shop visit on the effective date of this AD, the requirements of 
paragraph (g)(1) would apply at the next engine shop visit after the 
effective date of this AD.'' The FAA did not change this AD as a result 
of this comment.

Conclusion

    The FAA reviewed the relevant data, considered any comments 
received, and determined that air safety requires adopting this AD as 
proposed. Accordingly, the FAA is issuing this AD to address the unsafe 
condition on these products. Except for minor editorial changes, and 
any other changes described previously, this AD is adopted as proposed 
in the NPRM. None of the changes will increase the economic burden on 
any operator.

Costs of Compliance

    The FAA estimates that this AD affects 215 engines installed on 
airplanes of U.S. registry.
    The FAA estimates the following costs to comply with this AD:

[[Page 57727]]



                                                 Estimated Costs
----------------------------------------------------------------------------------------------------------------
                                                                                       Cost per    Cost on U.S.
                  Action                            Labor cost           Parts cost    product       operators
----------------------------------------------------------------------------------------------------------------
Replace LPC IBR-1........................  1 work-hours x $85 per hour      $36,350      $36,435      $7,833,525
                                            = $85.
Replace IGV key washers and install IGV    20 work-hours x $85 per            4,392        6,092       1,309,780
 spacers.                                   hour = $1,700.
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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

    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:

2024-14-04 International Aero Engines, LLC: Amendment 39-22785; 
Docket No. FAA-2024-0763; Project Identifier AD-2023-00924-E.

(a) Effective Date

    This airworthiness directive (AD) is effective August 20, 2024.

(b) Affected ADs

    None.

(c) Applicability

    This AD applies to International Aero Engines Model PW1122G-JM, 
PW1124G1-JM, PW1124G-JM, PW1127G1-JM, PW1127G1A-JM, PW1127G1B-JM, 
PW1127G-JM, PW1127GA-JM, PW1129G-JM, PW1130G-JM, PW1133G-JM, and 
PW1133GA-JM engines.

(d) Subject

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

(e) Unsafe Condition

    This AD was prompted by an in-flight shutdown caused by the 
fracture of a low-pressure compressor (LPC) 1st-stage integrally 
bladed rotor (IBR-1). The FAA is issuing this AD to prevent the 
failure of the LPC IBR-1. The unsafe condition, if not addressed, 
could result in damage to the engine, damage to the airplane, and 
possible loss of the airplane.

(f) Compliance

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

(g) Required Actions

    (1) For affected engines that have not incorporated Pratt & 
Whitney Service Bulletin PW1000G-C-72-00-0180-00A-930A-D (initial 
issue or any revision), and with installed LPC key washers having 
part number (P/N) 5375416, at the next engine shop visit after the 
effective date of this AD, remove the affected LPC key washers and 
replace them with LPC key washers and LPC inlet guide vane (IGV) 
spacers that are eligible for installation.
    (2) For affected engines with an installed LPC IBR-1 having P/N 
5373831, at the next piece-part exposure after the effective date of 
this AD, remove the affected LPC IBR-1 and replace with an LPC IBR-1 
eligible for installation.

(h) Definitions

    For the purposes of this AD:
    (1) An ``engine shop visit'' is the induction of an engine into 
the shop for maintenance involving the separation of pairs of major 
mating engine flanges, except that the separation of engine flanges 
solely for the purposes of transportation without subsequent engine 
maintenance does not constitute an engine shop visit.
    (2) A ``piece-part exposure'' is when the LPC IBR-1 is separated 
from the LPC module.
    (3) ``LPC key washers eligible for installation'' are any LPC 
key washers having P/N 5375434 or later-approved P/N.
    (4) ``LPC IGV spacers eligible for installation'' are any LPC 
IGV spacers having P/N 5375433 or later-approved P/N.
    (5) An ``LPC IBR-1 eligible for installation'' is any LPC IBR-1 
having P/N 5373841 or later-approved P/N.

(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 AIR-520 Continued Operational 
Safety Branch, send it to the attention of the person identified in 
paragraph (j) 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.

(j) 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].

(k) Material Incorporated by Reference

    None.


[[Page 57728]]


    Issued on July 10, 2024.
Peter A. White,
Deputy Director, Integrated Certificate Management Division, Aircraft 
Certification Service.
[FR Doc. 2024-15466 Filed 7-15-24; 8:45 am]
BILLING CODE 4910-13-P