[Federal Register Volume 89, Number 60 (Wednesday, March 27, 2024)]
[Rules and Regulations]
[Pages 21181-21190]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2024-06419]


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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2023-2401; Project Identifier AD-2023-01278-E; 
Amendment 39-22703; AD 2024-05-11]
RIN 2120-AA64


Airworthiness Directives; International Aero Engines, LLC Engines

AGENCY: Federal Aviation Administration (FAA), DOT.

ACTION: Final rule.

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SUMMARY: The FAA is superseding Airworthiness Directive (AD) 2022-19-15 
for certain International Aero Engines, LLC (IAE LLC) Model PW1100G 
series engines; and AD 2023-16-07 for certain IAE LLC Model PW1100G 
series engines and PW1400G series engines. AD 2022-19-15 required an 
angled ultrasonic inspection (AUSI) of the high-pressure turbine (HPT) 
1st-stage disk and HPT 2nd-stage disk, and replacement, if necessary. 
AD 2023-16-07 required an AUSI of the HPT 1st-stage hub (also known as 
the HPT 1st-stage disk) and HPT 2nd-stage hub (also known as the HPT 
2nd-stage disk) for cracks, and replacement, if necessary, which is 
terminating action for AD 2022-19-15. This AD was prompted by an 
investigation that determined an increased risk of powdered metal 
anomalies for all powdered metal parts in certain powdered metal 
production campaigns, which are susceptible to failure significantly 
earlier than previously determined. This AD retains the AUSI 
requirement for certain HPT 1st-stage and HPT 2nd-stage hubs from AD 
2023-16-07. This AD requires performing an AUSI of the HPT 1st-stage 
hub, HPT 2nd-stage hub, high-pressure compressor (HPC) 7th-stage 
integrally bladed rotor (IBR-7), and HPC 8th-stage integrally bladed 
rotor (IBR-8) for cracks, and replacing if necessary. This AD also 
requires accelerated replacement of the HPC IBR-7, HPC IBR-8, HPC rear 
hub, HPT 1st-stage hub, and HPT 2nd-stage hub. The FAA is issuing this 
AD to address the unsafe condition on these products.

DATES: This AD is effective April 11, 2024.
    The Director of the Federal Register approved the incorporation by 
reference of certain publications listed in this AD as of April 11, 
2024.
    The Director of the Federal Register approved the incorporation by 
reference of a certain other publication listed in this AD as of August 
28, 2023 (88 FR 56999, August 22, 2023).
    The Director of the Federal Register approved the incorporation by 
reference of a certain other publication listed in this AD as of 
November 7, 2022 (87 FR 59660, October 3, 2022; corrected October 24, 
2022 (87 FR 64156)).

ADDRESSES: 
    AD Docket: You may examine the AD docket at regulations.gov under 
Docket No. FAA-2023-2401; 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.
    Material Incorporated by Reference:
     For Pratt & Whitney (PW) service information that is 
incorporated by reference, contact International Aero Engines, LLC, 400 
Main Street, East Hartford, CT 06118; phone: (860) 565-0140; email: 
[email protected]; website: connect.prattwhitney.com.
     You may view this service information that is incorporated 
by reference at the FAA, Airworthiness Products Section, Operational 
Safety Branch, 1200 District Avenue, Burlington, MA 01803. For 
information

[[Page 21182]]

on the availability of this material at the FAA, call (817) 222-5110. 
It is also available at regulations.gov under Docket No. FAA-2023-2401.

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 (referred to herein 
as the NPRM) to amend 14 CFR part 39 to supersede AD 2022-19-15, 
Amendment 39-22184 (87 FR 59660, October 3, 2022; corrected October 24, 
2022 (87 FR 64156)) (AD 2022-19-15); and AD 2023-16-07, Amendment 39-
22526 (88 FR 56999, August 22, 2023) (AD 2023-16-07). AD 2022-19-15 
applied to certain IAE LLC Model PW1122G-JM, PW1124G1-JM, PW1124G-JM, 
PW1127G1-JM, PW1127GA-JM, PW1127G-JM, PW1129G-JM, PW1130G-JM, PW1133GA-
JM, and PW1133G-JM engines. AD 2023-16-07 applied to certain IAE LLC 
Model PW1122G-JM, PW1124G1-JM, PW1124G-JM, PW1127G-JM, PW1127G1-JM, 
PW1127GA-JM, PW1129G-JM, PW1130G-JM, PW1133G-JM, PW1133GA-JM, PW1428G-
JM, PW1428GA-JM, PW1428GH-JM, PW1431G-JM, PW1431GA-JM, and PW1431GH-JM 
engines. The NPRM published in the Federal Register on December 28, 
2023 (88 FR 89627). The NPRM was prompted by manufacturer analysis of 
an HPC IBR-7 failure that determined it was caused by a powdered metal 
anomaly that is similar in nature to the anomalies outlined in AD 2022-
19-15. The analysis concluded that there is an increased risk of 
failure for additional powdered metal parts in certain powdered metal 
production campaigns, including the HPC IBR-7 and HPC IBR-8, and that 
all affected parts are susceptible to failure significantly earlier 
than previously determined. The condition, if not addressed, could 
result in uncontained hub failure, release of high-energy debris, 
damage to the engine, damage to the airplane, and loss of the airplane.
    To address the unsafe condition, the FAA issued an NPRM (Docket No. 
FAA-2023-2237; Project Identifier AD-2023-01057-E) (referred to herein 
as the previous NPRM) to supersede AD 2022-19-15 and AD 2023-16-07, 
which was published in the Federal Register on December 12, 2023 (88 FR 
86088). However, after the previous NPRM was issued, the FAA received 
information from PW that an error was inadvertently included in the 
previous NPRM's compliance times for some of the HPT 1st-stage and 2nd-
stage hubs, which would have required removal significantly later than 
necessary. Due to the need to shorten the removal timeframe, the FAA 
determined it was necessary to withdraw the previous NPRM and issue the 
NPRM for the unsafe condition with the correct compliance times.
    In the NPRM, the FAA proposed to continue to require performing an 
AUSI of the HPT 1st-stage hub and HPT 2nd-stage hub and replacing as 
necessary. The NPRM proposed to require performing an AUSI of the HPC 
IBR-7 and HPC IBR-8 for cracks and replacing as necessary. The NPRM 
also proposed to require accelerated replacement of the HPC IBR-7, HPC 
IBR-8, HPC rear hub, HPT 1st-stage hub, HPT 1st-stage air seal, HPT 
1st-stage blade retaining plate, HPT 2nd-stage hub, HPT 2nd-stage blade 
retaining plate, and HPT 2nd-stage rear seal. 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 14 commenters, including the Air 
Line Pilots Association, International (ALPA); Air New Zealand; All 
Nippon Airways CO., LTD. (ANA); Delta Air Lines, Inc. (DAL); Hawaiian 
Airlines; Hong Kong Express Airways Limited (HK Express); InterGlobe 
Aviation Limited (IndiGo); JetBlue Airways (JetBlue); Lufthansa Group 
PW1100G-JM Operators: Lufthansa, SWISS International, Austrian, 
Lufthansa Cityline (Lufthansa Group); Lufthansa Technik AG; MTU 
Maintenance Hannover GmbH; PW; United Airlines; and Vietnam Airlines 
JSC. ALPA urged the manufacturer to develop measures to minimize the 
operational impact these inspections will have on operators but 
supported the proposed AD without change. Thirteen commenters requested 
changes to the proposed AD. The following presents the comments 
received on the NPRM and the FAA's response to each comment.

Request To Update Service Information

    Three commenters, Delta, JetBlue, and Lufthansa Technik AG 
requested that the FAA revise paragraphs (h)(2), (h)(6), and (m)(3)(ii) 
of the proposed AD to refer to PW ASB PW1000G-C-72-00-0225-00A-930A-D, 
Issue 002, dated December 12, 2023, rather than PW ASB PW1000G-C-72-00-
0225-00A-930A-D, Issue 001, dated November 3, 2023. Lufthansa Technik 
AG noted that it would be beneficial to use the latest SB revision in 
sections (h), (i), and (j) of the proposed AD.
    The FAA agrees. PW Alert Service Bulletin (ASB) PW1000G-C-72-00-
0225-00A-930A-D, Issue No: 002, dated December 12, 2023, adds 
alternative methods of AUSI compliance to the Compliance section, adds 
service information to the References section, and removes unnecessary 
steps from the Accomplishment Instructions. The FAA revised this AD to 
refer to PW ASB PW1000G-C-72-00-0225-00A-930A-D, Issue No: 002, dated 
December 12, 2023. The FAA also revised paragraph (j), Credit for 
Previous Actions, of this AD to allow credit for certain actions 
performed in accordance with PW ASB PW1000G-C-72-00-0225-00A-930A-D, 
Issue No: 001, dated November 3, 2023.

Request To Add Service Information

    One commenter, Lufthansa Technik AG, requested the addition of the 
following documents to the Related Service Information Under 1 CFR part 
51 paragraph of the NPRM:
     Special Instruction (SI) 46F-23A, dated April 4, 2023, 
which provides instructions to inspect IBR-7 parts;
     SI 47F-23A, dated April 4, 2023, which provides 
instructions to inspect IBR-8 parts; and
     SI 169F-23B, dated October 11, 2023, and previous, which 
provides a procedure to inspect all affected hardware in-shop.
    Lufthansa Technik AG noted that SI 169F-23B should be added to the 
proposed AD to ensure that credit can be taken from last accomplishment 
of this SI.
    The FAA disagrees. The Related Service Information Under 1 CFR part 
51 paragraph contains service information that is incorporated by 
reference in this AD, and the above-referenced service information is 
not incorporated by reference. The FAA did not change this final rule 
as a result of this comment.

Request To Allow Future Revisions of Service Information

    Three commenters, ANA, Hawaiian Airlines, and HK Express Airways 
requested the FAA add ``or later'' to SI No. 222F-23 in the AD or to 
consider not requiring a specific SI No. 222F-23 revision. The 
commenters noted that this SI will be revised periodically and 
suggested that the later revisions should also be exempt from the 
proposed AD. One commenter, ANA, also requested that the FAA add the 
phrase ``or later

[[Page 21183]]

revision'' to each service information (Service Bulletin and PW Special 
Instruction) stated in paragraph (m) of the proposed AD.
    The FAA disagrees with adding ``or later'' or ``or later revision'' 
for service information incorporated by reference in this AD. Future 
revisions of the service information have not yet been published by the 
manufacturer or reviewed by the FAA, and therefore cannot be approved 
as required service information. A request for an alternative method of 
compliance (AMOC) can be submitted to the FAA in accordance with the 
requirements of paragraph (k) of this AD if future revisions of the 
service information referenced in this AD are published. Additionally, 
if future revisions of the service information are published by the 
manufacturer and approved by the FAA, the FAA may consider further 
rulemaking. The FAA did not change this AD as a result of these 
comments.

Request To Exclude Unaffected Parts

    Eleven commenters, ANA, DAL, Hawaiian Airlines, HK Express Airways, 
IndiGo, JetBlue, Lufthansa Group, Lufthansa Technik AG, MTU Maintenance 
Hannover GmbH, PW, and United Airlines, recommended the FAA exempt the 
HPC IBR-7, HPC IBR-8, HPC Rear Hub, HPT 1st stage hub, and HPT 2nd 
stage hub serial numbers listed in Tables 1, 2, and 3 of PW SI No. 
222F-23 from the requirements set forth in the proposed AD. PW 
explained that SI No. 222F-23 identifies specific part numbers and 
serial numbers that were manufactured outside the affected population 
of material manufactured from powdered metal addressed by the proposed 
AD. PW requested modifying the ``Applicability'' section of the 
proposed AD to exclude parts which are not in the affected population.
    The FAA agrees. The FAA will revise paragraph (c), Applicability, 
of this AD to reference Tables 1, 2, and 3 of PW SI No. 222F-23, 
Revision A, dated February 13, 2024, which specifies part numbers and 
serial numbers verified as manufactured from powdered metal campaigns 
produced prior to November 1, 2015, or after September 1, 2021, and 
which are therefore outside the population of material manufactured 
from powdered metal addressed by this AD. This change in the 
applicability reduces the affected part numbers and serial numbers.

Request Clarification on IBR-8 Part Numbers

    Lufthansa Technik AG commented that two IBR-8 P/Ns, 30G3808 and 
30G6308, are listed in the Illustrated Parts Catalog and in the 
airworthiness limitations, but not in the proposed AD. The commenter 
asked for clarification that these part numbers do not require AUSI and 
have no additional part replacement but are not allowed for 
reinstallation in accordance with paragraph (i)(5) of the proposed AD. 
The commenter suggested this could be due to low life-limited part 
life.
    For clarity, the FAA did not address HPC IBR-8 having P/N 30G3808 
and 30G6308 in this AD because the FAA has determined that those parts 
are either retired, out of service, or have airworthiness limitations 
that are more restrictive than the requirements of this AD. The FAA did 
not change this AD as a result of this comment.

Request To Modify Paragraph (g) of the Proposed AD To Include Certain 
Part Numbers

    Lufthansa Technik AG requested that the FAA review the inclusion of 
all four affected HPT Stg 1 and Stg 2 part numbers in paragraphs (g)(1) 
and (2) of the proposed AD for completeness of retaining the 
requirements of AD 2023-16-07 with no change.
    The FAA disagrees. Paragraph (g), Retained Inspections from AD 
2023-16-07, With No Changes, of this AD applies to certain part and 
serial numbers as specified. The FAA did not change this AD as a result 
of this comment.

Request To Modify the Compliance Language in Paragraph (g) of the 
Proposed AD

    One commenter, ANA, requested to change the required action 
specified in paragraph (g) of the proposed AD from ``perform an AUSI of 
the affected parts within 30 days,'' to ``remove the affected engine 
from service within 30 days, and thereafter perform an AUSI of the 
affected part before release to service.''
    The FAA disagrees. The commenter provided no justification for the 
request, and the FAA has determined that this AD as written 
accomplishes the same result requested by the commenter. The FAA did 
not change this AD as a result of this comment.

Request To Remove References to Certain Parts

    Two commenters, Air New Zealand and PW, observed that Table 3 of 
the proposed AD includes a reference to components that are not 
affected by the powdered metal issue and are not referenced in PW SB 
PW1000G-C-72-00-0224 and PW1000G-C-72-00-0225. Air New Zealand 
suggested that including these in the proposed AD would create 
confusion and unnecessary complexity when processing and showing 
compliance. PW noted that the proposed AD would not require accelerated 
replacement of HPT 1st-stage front air seal, HPT 2nd-stage rear air 
seal, HPT 1st-stage blade retaining plate, and HPT 2nd-stage blade 
retaining plate, and further noted that these parts would be 
automatically replaced with incorporation of the Block D 1st and 2nd 
stage turbine disks. Air New Zealand requested the removal of the 
references to the HPT 1&2 air seals and the HPT Stage 1 & 2 retaining 
plates.
    The FAA agrees. The FAA will remove the references to HPT 1st-stage 
front air seal, HPT 2nd-stage rear air seal, HPT 1st-stage blade 
retaining plate, and HPT 2nd-stage blade retaining plate from this AD.

Request To Include Calculation for Mixed Model Management

    Three commenters, ANA, Lufthansa Group, and Lufthansa Technik AG, 
observed that a mixed model management calculation as defined in PW ASB 
PW1000G-C-72-00-0224-00A-930A-D and PW ASB PW1000G-C-72-00-0225-00A-
930A-D is not mentioned in the proposed AD. Lufthansa Technik AG 
suggested that this calculation is also referenced in SIL 17. Lufthansa 
Group noted that, without a stated reference to the mixed model 
management calculation, it is possible that engines operated at any 
time at the higher thrust rating must be treated as such. The 
commenters requested that the FAA state in the proposed AD that mixed 
model management calculation can be applied to address parts that have 
operated in both Group 1 and Group 2 engines.
    The FAA agrees. The FAA will revise paragraph (h), New Required 
Actions, of this AD to address the calculation of cyclic limits for 
part replacement and AUSI compliance times for parts that have been 
installed in a Group 1 and Group 2 configuration as defined in the note 
to Table 3 of the compliance paragraph of PW ASB PW1000G-C-72-00-0224-
00A-930A-D, Issue No: 001 and PW1000G-C-72-00-0225-00A-930A-D, Issue 
No: 002. The FAA has not reviewed SIL 17 and will not reference this 
service information in this AD.

Request To Add a Cyclic Limit to Paragraph (h)(1) of the Proposed AD

    One commenter, Lufthansa Technik AG, requested the FAA add a cyclic 
limit to paragraph (h)(1) of the proposed AD. The commenter noted that 
all affected hardware is covered by the 100-flight cycle (FC) timeframe 
in paragraph (h)(9) of the proposed AD. The

[[Page 21184]]

commenter suggested that, since there are other unrelated issues in the 
HPC, and as there is no cyclic limitation planned for the AUSI of the 
HPC parts, the FAA exclude the requirement to perform an AUSI in 
accordance with paragraph (h)(1) of the proposed AD below 500 FCs since 
the last AUSI or since new, unless the HPC rotor is disassembled. The 
commenter explained that this would remove the need to inspect parts 
that were recently installed but removed for access.
    The FAA disagrees. The FAA cannot account for all circumstances 
that would require an engine shop visit. Unusual engine shop visit 
circumstances may be considered through the provisions of paragraph 
(k), Alternative Methods of Compliance, of this AD. The FAA did not 
change this AD as a result of this comment.

Request To Clarify Discrepancy in Compliance Times Between the Proposed 
AD and the PW ASB

    Two commenters, DAL and IndiGo, noted a discrepancy between the 
compliance times in the proposed AD and those in the PW ASBs. IndiGo 
requested that the FAA clarify if the compliance timeline in the 
proposed AD supersedes the compliance timeline in the PW ASBs, and if 
the operators can wait for the proposed AD to be issued and follow the 
effective date stated in the proposed AD. DAL requested that the FAA 
add a paragraph or revise paragraph (h)(2) to address the 100-FC 
drawdown periods in the proposed AD and the discrepancy between the 
compliance times of the AD and the PW ASBs.
    The FAA disagrees with adding a paragraph. Operators are required 
to comply within the compliance times specified in this AD. However, 
how an operator reacts to recommended actions from the design approval 
holder (DAH) should be spelled out in their approved maintenance 
program and is not governed by this AD. The FAA did not change this AD 
as a result of this comment.

Request To Adjust Compliance Time To Account for Cycle Count

    One commenter, Vietnam Airlines, observed that the drawdown cycles 
for mandated actions (such as part replacement or inspection) shall be 
contingent upon the cycle count surpassing the compliance threshold 
outlined in Table 1 to Paragraph (h)(2) and Table 2 to Paragraph (h)(3) 
of the proposed AD. The commenter suggested that there should be 
distinctions in treatment between an engine exceeding the threshold by 
1,000 cycles and one exceeding the threshold by 200 cycles. Should the 
former exhibit a drawdown period of 100 cycles, the commenter 
recommended that the latter be allocated a longer period for 
compliance.
    The FAA disagrees. The FAA determined that a tiered drawdown is not 
necessary because all parts exceeding the compliance time or cycle 
limit stated in Table 1 to paragraph (h)(2) and Table 2 to paragraph 
(h)(3) of this AD must be removed within 100 FCs after the effective 
date of this AD. The FAA did not change this AD as a result of this 
comment.

Request To Include Life Reduction for Certain HPC Rear Hub

    One commenter, ANA, noted that the compliance times for HPC rear 
hub having P/N 30G4008 are specified in ASB PW1000G-C-72-00-0224-00A-
930A-D, but they are not included in Table 3 of the proposed AD. 
Therefore, the commenter observed, an engine may be used beyond the 
compliance times specified in ASB PW1000G-C-72-00-0224-00A-930A-D. ANA 
requested that the proposed AD be revised to include the compliance 
times for P/N 30G4008 specified in ASB PW1000G-C-72-00-0224-00A-930A-D.
    The FAA disagrees. This AD requires the removal of HPC rear hub 
having P/N 30G4008 at either the next HPC engine shop visit or the next 
HPT engine shop visit, whichever occurs first. The FAA determined that 
it is not necessary to specify a compliance time for HPC rear hub 
having P/N 30G4008 due to the cycle limits for the associated HPC and 
HPT parts. The FAA did not change this AD as a result of this comment.

Request To Change ``Crack'' to ``Defect'' in Paragraph (h)(8) of the 
Proposed AD

    One commenter, Lufthansa Technik AG, observed that paragraph (h)(8) 
of the proposed AD requires to remove only parts found with a crack. 
The commenter stated that due to AUSI procedure, it cannot be 
determined if it is a crack or just an anomaly. Therefore, the 
commenter requested that the FAA change the wording so that all parts 
with defects will be removed from service.
    The FAA partially agrees. The FAA does not agree with the wording 
proposed by the commenter. The FAA agrees to meet the commenter's 
intent by changing the wording of paragraph (h)(9) of this AD from ``if 
any crack is found,'' to ``if any crack indication is found.''

Request To Include Reference to New Parts

    One commenter, Lufthansa Technik AG, requested that the FAA change 
paragraph (h)(9) of the proposed AD to read ``[. . .] 100 FCs or less 
since the last AUSI OR NEW, (re-)inspection [. . .].'' The commenter 
explained that this would allow also counting from reinstallation of 
new hardware (where it cannot be determined if the AUSI was performed 
during production at OEM).
    The FAA disagrees. Paragraph (h)(10) of this AD applies to 
repetitive inspections of affected parts installed within the last 100 
FCs. Parts that are not included in paragraph (c), Applicability, of 
this AD are not subject to the repetitive AUSI requirement. The FAA did 
not change this AD as a result of this comment.

Request To Revise Heading of Table 1 to Paragraph (h)(2) of the 
Proposed AD

    One commenter, Lufthansa Technik AG, noted that it would avoid 
confusion to reference HPT hub stage 1 and 2 only in the heading of 
Table 1 to (h)(2). The commenter requested that the FAA include the 
part names in the header of the table.
    The FAA disagrees. The FAA has determined that including the part 
names in the header is not necessary because paragraph (h)(2) specifies 
the parts and part numbers subject to the compliance time specified in 
Table 1 to Paragraph (h)(2) of this AD. The FAA did not change this AD 
as a result of this comment.

Request To Reference AUSI Performed in Service in Table 1 to (h)(2) of 
the Proposed AD

    One commenter, Lufthansa Technik AG, suggested that the new 
production parts inspection regime was updated and that Table 1 to 
(h)(2) of the proposed AD is not covering this AUSI inspection at 
production. The commenter requested that the second column of Table 1 
to (h)(2) of the proposed AD be revised to state that this reflects 
only ``AUSI performed in service prior to the effective date of this 
AD.''
    The FAA disagrees. However, the FAA has updated paragraph (c), 
Applicability, of this AD to exempt serial numbers listed in Tables 1, 
2, and 3 of SI 222F-23, Revision A, which includes parts subject to 
AUSI at production.

Request To Add Airworthiness Limitation to Table 2 to Paragraph (h)(3) 
of the Proposed AD

    One commenter, Lufthansa Technik AG, noted that in Table 2 to 
paragraph

[[Page 21185]]

(h)(3) of the proposed AD, for Group 1 engines, the 1st-Stage Hub P/N 
30G4201 or 30G6201 with AUSI performed refers to 3,800 FCs since the 
last AUSI. The commenter also noted that for Group 2 engines, the 1st-
Stage Hub P/N 30G4201 or 30G6201 with AUSI performed refers to 2,800 
FCs since the last AUSI. The commenter observed that the part needs 
removal within the airworthiness limitation. The commenter requested 
that the FAA add a statement similar to the 2nd-stage hubs.
    The FAA disagrees. The FAA has determined that adding such a 
statement is unnecessary because the existing airworthiness limitations 
are more restrictive. The FAA did not change this AD as a result of 
this comment.

Request To Make Changes to Tables

    Three commenters, HK Express Airways, JetBlue, and Lufthansa 
Technik AG, expressed that the lack of borderlines in Table 2 for 
paragraph (h)(3) and Table 3 for paragraph (h)(4) of the proposed AD is 
confusing. Lufthansa Technik AG notes that on the first look, it seems 
that the compliance time for part removal at next HPT shop visit is 
applicable to one row only, but in fact should be applicable for all 
parts listed below. The commenters requested that the FAA complete the 
engine group and compliance time boxes for each line item listed in 
Table 2 and Table 3 of the proposed AD.
    The FAA agrees. The FAA has revised Table 2 to paragraph (h)(3) and 
Table 3 to paragraph (h)(4) of this AD to complete the engine group and 
compliance time columns for each line item.

Request To Provide Additional Cycles for Alternate Climb Operations

    One commenter, JetBlue, stated that JetBlue has been operating with 
the Alternate Climb modification on the fleet. The commenter explained 
that the Alternate Climb modification is performed pre-delivery and 
decreases work/stress on the engine during the entire climb duration, 
which effectively alleviates stress/fatigue. The commenter requested 
that the FAA analyze the data to check the feasibility of providing 
additional cycles for the Alternate Climb modification to meet the 
proposed AD timelines.
    The FAA disagrees. Operators can submit a request for an AMOC to 
the FAA in accordance with the requirements of paragraph (k) of this AD 
with the data that shows the modification provides an acceptable level 
of safety. The FAA did not change this AD in response to this comment.

Request To Modify Definition for Part Eligible for Installation

    One commenter, HK Express Airways, noted that PW SI 222F-23 
identifies parts exempted from repetitive AUSI and early retirement 
carrying the same part number, and the commenter observed that the 
proposed AD did not mention this SI in paragraph (i). HK Express 
Airways requested adding reference to SI 222F-23 to the definition of 
``part eligible for installation,'' so the parts listed in the SI are 
deemed to be eligible for installation. The commenter also noted that 
SI 222F-23 will be updated quarterly by PW, therefore the AD should not 
fix the SI version.
    The FAA agrees to revise the definition of ``part eligible for 
installation'' in paragraph (i) of this AD to reference part serial 
numbers identified in Tables 1, 2, and 3 of SI 222F-23, Revision A. The 
FAA does not agree to include an undated reference to SI 222F-23. 
Future revisions of service information have not yet been published by 
the manufacturer or reviewed by the FAA, and therefore cannot be 
approved as required service information. A request for an AMOC can be 
submitted to the FAA in accordance with paragraph (k) of this AD if 
future revisions of the service information referenced in this AD are 
published. Additionally, if future revisions of the service information 
are published by the manufacturer and approved by the FAA, the FAA may 
consider further rulemaking.

Request To Clarify if Newly Produced Parts Are Eligible for 
Installation

    Three commenters, DAL, HK Express Airways, and Lufthansa Technik 
AG, observed that the proposed AD did not address newly produced parts 
carrying the same part number in the definition of ``part eligible for 
installation'' in paragraph (i)(5) of the proposed AD. Therefore, the 
commenters reasoned, the proposed AD does not define installation 
eligibility for any new/not service run HPC/HPT hardware that is not 
currently installed on a Group 1 or Group 2 engine. The commenters 
requested that paragraph (i)(5) of the proposed AD be revised to add 
installation eligibility for new production parts.
    The FAA agrees. If the newly produced parts are manufactured from 
powdered metal material produced prior to November 1, 2015, or after 
September 1, 2021, as identified in the original manufacturing records 
or in Tables 1, 2, and 3 of SI No. 222F-23, Revision A, those parts are 
not affected by this AD. The FAA revised the definition of ``part 
eligible for installation'' in paragraph (i)(5) of this AD to reference 
parts identified as not affected by this AD in paragraph (c)(2) of this 
AD. Therefore, parts identified in Tables 1, 2, and 3 of SI No. 222F-
23, Revision A, will meet the definition of ``part eligible for 
installation.'' To meet the updated definition of ``part eligible for 
installation,'' affected parts need to be inspected in accordance with 
this AD. Unaffected parts can be installed without performing the 
requirements of this AD.

Request To Clarify Meaning of Induction as Used in Paragraph (i), 
Definitions, of the Proposed AD

    One commenter, ANA, asked the FAA to clarify that the definition of 
``induction'' in paragraph (i) of the proposed AD is the timing when 
the engine disassembly is started. ANA asked the FAA to clarify a 
particular situation to have a correct understanding. ANA noted that, 
in terms of paragraph (h)(1) and (2) of the proposed AD, if an engine 
is already in shop for maintenance involving the separation H-flange or 
M-flange, then assembly has already been started at the effective date 
of this AD. The commenter asked if an angled ultrasonic scan inspection 
should therefore not be performed in this shop visit.
    The FAA agrees to clarify. The FAA does not have a set definition 
for induction. Reference your approved maintenance program to determine 
what ADs apply to your engines during an engine shop visit. In the 
example provided, if the engine were already at an engine shop visit on 
the effective date of this AD, the requirements of paragraphs (h)(1) 
and (2) would apply at the next engine shop visit after the effective 
date of this AD. The FAA did not change this AD in response to this 
comment.

Request To Include 2nd-Stage HPT Retaining Plates in Paragraph (i), 
Definitions, of the Proposed AD

    One commenter, Lufthansa Technik AG, requested that the FAA include 
2nd-stage HPT retaining plates in the definition of parts eligible for 
installation.
    The FAA disagrees. The FAA revised this final rule to remove 
references to HPT retaining plates in response to another comment. The 
FAA did not change this AD in response to this comment.

[[Page 21186]]

Request To Identify Previous AUSI Service Information in Paragraph (j), 
Credit for Previous Actions, of the Proposed AD

    One commenter, Lufthansa Technik AG, observed that, in addition to 
the credit for paragraphs (g)(1) and (2) of the proposed AD, it should 
be required to note down which procedures qualify as ``AUSI performed'' 
for cyclic requirements under paragraphs (h)(2) with table 1 and (h)(8) 
of the proposed AD to correctly determine the remaining life and if the 
AUSI was performed prior to AD e[fflig]ectivity. The commenter listed 
the following service information: For HPT hubs in accordance with 
(h)(2) and (8) of the proposed AD:
     SI 169F-23;
     SB PW1000G-C-72-00-0188-00A-930A-D, Issue 1 dated 
September 13, 2021; and
     PW1000G-C-72-00-0188-00A-930A-D, Issue 2 dated July 8, 
2022.
    For HPC parts in accordance with paragraph (h)(8) of the proposed 
AD:
     SI 46F-23; and
     SI 47F-23.
    The FAA infers that the commenter requested that the FAA add the 
service information identified to paragraph (j), Credit for Previous 
Actions, of this AD. The FAA disagrees. PW SB PW1000G-C-72-00-0188-00A-
930A-D, Issue No: 001, dated September 13, 2021, is referenced in 
paragraph (j), Credit for Previous Actions, of this AD. The FAA revised 
paragraph (j), Credit for Previous Actions, of this AD to include PW 
ASB PW1000G-C-72-00-0225-00A-930A-D, Issue No. 001, dated November 3, 
2023, which provides methods for AUSI that may have been previously 
used, in response to a separate comment. The FAA did not change this AD 
in response to this comment.

Request To Add Special Flights Permit Paragraph

    One commenter, HK Express Airways, noted that according to PW, non-
revenue maintenance or check flights are permitted if the aircraft is 
required to re-locate to base maintenance facilities for storage or 
engine removal after the compliance time. The commenter requested that 
the FAA add a paragraph to the proposed AD to clearly state that non-
revenue maintenance flights are permitted within the proposed AD.
    The FAA disagrees because 14 CFR 39.23 allows for special flight 
permits unless specified as limited or prohibited in the AD. The FAA 
did not change this AD in response to this comment.

Additional Change Made to the Applicability

    Since the NPRM published, the FAA determined the need to add IAE 
LLC Models PW1127G1A-JM and PW1127G1B-JM to paragraph (c), 
Applicability, in this AD. These engine models were recently 
certificated but are not in production yet. The FAA revised the 
applicability of this AD to include these additional engine models. 
None of the engines added to the applicability of this AD are on the 
U.S. Register. Additional notice and opportunity for public comment 
before issuing this AD are therefore unnecessary. Since there are no 
additional engines on the U.S. registry, no changes have been made to 
the Costs of Compliance paragraph in this final rule.

Updated Service Information for Paragraph (c)(2) of the Applicability

    Since the NPRM comment period closed, PW updated SI 222F-23, 
Revision A, to add additional part numbers and serial numbers verified 
as manufactured from powdered metal campaigns produced prior to 
November 1, 2015, or after September 1, 2021, and which are therefore 
outside the population of material manufactured from powdered metal 
addressed by this AD. For this reason, the FAA updated paragraph (c)(2) 
of the Applicability to reference Tables 1, 2, and 3 of PW SI No. 222F-
23, Revision B, dated March 1, 2024. This change to the applicability 
of this AD reduces the affected part numbers and serial numbers.

Conclusion

    The FAA reviewed the relevant data, considered any 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, 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.

Related Service Information Under 1 CFR Part 51

    The FAA reviewed the following service information:
     PW ASB PW1000G-C-72-00-0224-00A-930A-D, Issue No: 001, 
dated November 3, 2023, which specifies procedures for performing an 
AUSI for cracks on affected HPC IBR-7 and HPC IBR-8;
     PW ASB PW1000G-C-72-00-0225-00A-930A-D, Issue No: 002, 
dated December 12, 2023, which specifies procedures for performing an 
AUSI for cracks on affected HPT 1st-stage hubs and HPT 2nd-stage hubs;
     PW SI No. 198F-23, dated November 3, 2023, which specifies 
the list of affected HPT 1st-stage hubs and HPT 2nd-stage hubs, 
identified by part number and serial number, installed on certain IAE 
LLC engines;
     PW SI No. 222F-23, Revision B, dated March 1, 2024, which 
specifies the list of part numbers and serial numbers that were 
manufactured outside of the affected population of material 
manufactured from powdered metal;
     PW Service Bulletin PW1000G-C-72-00-0188-00A-930A-D, Issue 
No: 002, dated July 8, 2022, which was previously approved for 
incorporation by reference on November 7, 2022 (87 FR 59660, October 3, 
2022; corrected October 24, 2022 (87 FR 64156)). This service 
information specifies procedures for performing an AUSI for cracks on 
affected HPT 1st-stage hubs and HPT 2nd-stage hubs; and
     PW SI No. 149F-23, dated August 4, 2023, which was 
previously approved for incorporation by reference on August 28, 2023 
(88 FR 56999, August 22, 2023). This service information specifies the 
list of affected HPT 1st-stage hubs and HPT 2nd-stage hubs, identified 
by part number and serial number, installed on certain IAE LLC engines.
    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 the ADDRESSES section.

Interim Action

    The FAA considers this AD to be an interim action. The unsafe 
condition is still under investigation by the manufacturer and, 
depending on the results of that investigation, the FAA may consider 
further rulemaking action.

Justification for Determination of the Effective Date

    Section 553(d) of the Administrative Procedure Act (APA) (5 U.S.C. 
551 et seq.) authorizes agencies to make rules effective in less than 
thirty days, upon a finding of ``good cause.'' The FAA has found that 
the risk to the flying public justifies a shortened effective date for 
this rule due to powdered metal anomalies in HPT 1st-stage hub, HPT 
2nd-stage hub, HPC IBR-7, and HPC IBR-8 that could lead to premature 
fracture and uncontained failure, which could lead to the release of 
high-energy debris, damage to the engine, damage to the airplane, and 
loss of the airplane. The compliance time for replacement of

[[Page 21187]]

certain parts is within 100 flight cycles after the effective date of 
this AD, which is on average one calendar month of operation. The 
longer these parts remain in service, the higher the probability of 
failure. Additionally, the FAA did not receive any adverse comments or 
useful information about this AD from U.S. operators that necessitates 
waiting 30 days for this AD to become effective. Accordingly, the FAA 
finds that good cause exists pursuant to 5 U.S.C. 553(d) for making 
this amendment effective in less than 30 days.

Costs of Compliance

    The FAA estimates that this AD affects 430 engines installed on 
airplanes of U.S. registry. The FAA estimates that 366 engines will 
need replacement of the HPT 1st-stage hub; 351 engines will need 
replacement of the HPT 2nd-stage hub; 408 engines will need replacement 
of the HPC IBR-7; 368 engines will need replacement of the HPC IBR-8; 
and 283 engines will need replacement of the HPC rear hub.
    The FAA estimates the following costs to comply with this AD:

                                                 Estimated Costs
----------------------------------------------------------------------------------------------------------------
                                                                        Parts cost
                 Action                          Labor cost            (average pro-    Cost per   Cost on U.S.
                                                                        rated cost)     product      operators
----------------------------------------------------------------------------------------------------------------
AUSI of HPT 1st-stage hub, HPT 2nd-      80 work-hours x$85 per                    $0     $6,800      $2,924,000
 stage hub, HPC IBR-7, and HPC IBR-8      hour = $6,800.
 for cracks.
Replace HPT 1st-stage hub..............  10 work-hours x$85 per                56,000     56,850      20,807,100
                                          hour = $850.
Replace HPT 2nd-stage hub..............  10 work-hours x$85 per                62,000     62,850     $22,060,350
                                          hour = $850.
Replace HPC IBR-7......................  10 work-hours x$85 per                82,000     82,850      33,802,800
                                          hour = $850.
Replace HPC IBR-8......................  10 work-hours x$85 per                93,000     93,850      34,536,800
                                          hour = $850.
Replace HPC rear hub...................  10 work-hours x$85 per               132,000    132,850      37,596,550
                                          hour = $850.
----------------------------------------------------------------------------------------------------------------

    The FAA has included all known costs in its cost estimate. 
According to the manufacturer, however, some of the costs of this AD 
may be covered under warranty, thereby reducing the cost impact on 
affected operators.

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 has determined that 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:
0
a. Removing Airworthiness Directive 2022-19-15, Amendment 39-22184 (87 
FR 59660, October 3, 2022; corrected October 24, 2022 (87 FR 64156)); 
and Airworthiness Directive 2023-16-07, Amendment 39-22526 (88 FR 
56999, August 22, 2023); and
0
b. Adding the following new airworthiness directive:

2024-05-11 International Aero Engines, LLC: Amendment 39-22703; 
Docket No. FAA-2023-2401; Project Identifier AD-2023-01278-E.

(a) Effective Date

    This airworthiness directive (AD) is effective April 11, 2024.

(b) Affected ADs

    (1) This AD replaces AD 2022-19-15, Amendment 39-22184 (87 FR 
59660, October 3, 2022; corrected October 24, 2022 (87 FR 64156)).
    (2) This AD replaces AD 2023-16-07, Amendment 39-22526 (88 FR 
56999, August 22, 2023) (AD 2023-16-07).

(c) Applicability

    (1) This AD applies to International Aero Engines, LLC (IAE LLC) 
Model PW1122G-JM, PW1124G1-JM, PW1124G-JM, PW1127G-JM, PW1127G1-JM, 
PW1127G1A-JM, PW1127G1B-JM, PW1127GA-JM, PW1129G-JM, PW1130G-JM, 
PW1133G-JM, PW1133GA-JM, PW1428G-JM, PW1428GA-JM, PW1428GH-JM, 
PW1431G-JM, PW1431GA-JM, and PW1431GH-JM engines with an installed:
    (i) High-pressure compressor (HPC) 7th-stage integrally bladed 
rotor (IBR-7) having part number (P/N) 30G2307 or 30G4407;
    (ii) HPC 8th-stage integrally bladed rotor (IBR-8) having P/N 
30G5608, 30G5908, or 30G8908;
    (iii) HPC rear hub having P/N 30G4008 or 30G8208;
    (iv) High-pressure turbine (HPT) 1st-stage hub having P/N 
30G4201, 30G6201, or 30G7301; or
    (v) HPT 2nd-stage hub having P/N 30G3902, 30G5502, or 30G6602.
    (2) This AD does not apply to parts identified in paragraphs 
(c)(1)(i) through (v) of this AD if those parts were manufactured 
from powdered metal material produced prior to November 1, 2015, or 
after September 1, 2021, as identified by part serial number in 
Tables 1, 2, and 3 of PW Special Instruction (SI) No. 222F-23, 
Revision B, dated March 1, 2024 (PW SI No. 222F-23, Revision B) or 
in the original manufacturing records for the part.

[[Page 21188]]

    (3) If the original manufacturing records do not identify the 
production date of the powdered metal used to make the parts 
identified in paragraphs (c)(1)(i) through (v) of this AD, and the 
part serial number is not listed in Tables 1, 2, and 3 of PW SI No. 
222F-23, Revision B, then the part is subject to the requirements of 
this AD.

(d) Subject

    Joint Aircraft System Component (JASC) Code 7230, Turbine Engine 
Compressor Section; 7250, Turbine Section.

(e) Unsafe Condition

    This AD was prompted by an analysis of an event involving an IAE 
LLC Model PW1127GA-JM engine, which experienced failure of an HPC 
IBR-7 that resulted in an engine shutdown and aborted takeoff. The 
FAA is issuing this AD to prevent failure of the HPT 1st-stage hub, 
HPT 2nd-stage hub, HPC IBR-7, and HPC IBR-8. The unsafe condition, 
if not addressed, could result in 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) Retained Inspections From AD 2023-16-07, With No Changes

    (1) This paragraph restates the requirements of paragraph (g)(1) 
of AD 2023-16-07. For Group 1 and Group 2 engines with an installed 
HPT 1st-stage hub having part number (P/N) 30G7301 and a serial 
number (S/N) listed in Tables 1, 2, 3, or 4 of PW Special 
Instruction (SI) No. 149F-23, dated August 4, 2023 (PW SI No. 149F-
23), within 30 days after August 28, 2023 (the effective date of AD 
2023-16-07), perform an AUSI of the HPT 1st-stage hubs for cracks in 
accordance with the Accomplishment Instructions, paragraph 9.A. or 
9.B., as applicable, of Pratt & Whitney (PW) Service Bulletin 
PW1000G-C-72-00-0188-00A-930A-D, Issue No: 002, dated July 8, 2022 
(PW1000G-C-72-00-0188-00A-930A-D, Issue No: 002).
    (2) This paragraph restates the requirements of paragraph (g)(2) 
of AD 2023-16-07. For Group 1 and Group 2 engines with an installed 
HPT 2nd-stage hub having P/N 30G6602 and an S/N listed in Tables 1, 
2, 3, or 4 of PW SI No. 149F-23, within 30 days after August 28, 
2023 (the effective date of AD 2023-16-07), perform an AUSI of the 
HPT 2nd-stage hubs for cracks in accordance with the Accomplishment 
Instructions, paragraph 9.C. or 9.D., as applicable, of PW1000G-C-
72-00-0188-00A-930A-D, Issue No: 002.

(h) New Required Actions

    (1) For Group 1 and Group 2 engines with an affected HPC IBR-7 
having P/N 30G2307 or 30G4407, or an affected HPC IBR-8 having P/N 
30G5608, 30G5908, or 30G8908, at the next HPC engine shop visit and 
thereafter at every HPC engine shop visit, perform an angled 
ultrasonic scan inspection (AUSI) of the affected HPC IBR-7 or HPC 
IBR-8, as applicable, for cracks in accordance with the 
Accomplishment Instructions, paragraph 4.E.(1) or 4.E.(2), of PW 
Alert Service Bulletin (ASB) PW1000G-C-72-00-0224-00A-930A-D, Issue 
No: 001, dated November 3, 2023 (PW ASB PW1000G-C-72-00-0224-00A-
930A-D, Issue No: 001).
    (2) For Group 1 and Group 2 engines with an affected HPT 1st-
stage hub having P/N 30G7301 or an HPT 2nd-stage hub having P/N 
30G6602, before exceeding the applicable compliance time in Table 1 
to paragraph (h)(2) of this AD, except as required by paragraphs 
(g)(1) and (2) and paragraph (h)(7) of this AD, perform an AUSI of 
the affected HPT 1st-stage hub or HPT 2nd-stage hub, as applicable, 
for cracks in accordance with the Accomplishment Instructions, 
paragraph 1.D.(7)(a) or 1.D.(7)(b) of PW ASB PW1000G-C-72-00-0225-
00A-930A-D, Issue No: 002, dated December 12, 2023 (PW ASB PW1000G-
C-72-00-0225-00A-930A-D, Issue No: 002). Thereafter, repeat the AUSI 
at the applicable interval in Table 1 to paragraph (h)(2) of this 
AD.

           Table 1 to Paragraph (h)(2)--AUSI Compliance Times
------------------------------------------------------------------------
               AUSI performed prior to
Engine group   effective date of this   Compliance time     Repetitive
                         AD                                  interval
------------------------------------------------------------------------
1...........  No......................  Before           Thereafter at
                                         accumulating     each HPT
                                         3,800 cycles     engine shop
                                         since new        visit or
                                         (CSN) or         before
                                         within 100       exceeding
                                         flight cycles    3,800 FCs from
                                         (FCs) after      the last AUSI
                                         the effective    of the
                                         date of this     affected hub,
                                         AD, whichever    whichever
                                         occurs later.    occurs first.
1...........  Yes.....................  At the next HPT  Thereafter at
                                         engine shop      each HPT
                                         visit, not to    engine shop
                                         exceed 3,800     visit or
                                         FCs since the    before
                                         previous AUSI,   exceeding
                                         or within 100    3,800 FCs from
                                         FCs after the    the last AUSI
                                         effective date   of the
                                         of this AD,      affected hub,
                                         whichever        whichever
                                         occurs later.    occurs first.
2...........  No......................  Before           Thereafter at
                                         accumulating     each HPT
                                         2,800 CSN or     engine shop
                                         within 100 FCs   visit or
                                         after the        before
                                         effective date   exceeding
                                         of this AD,      2,800 FCs from
                                         whichever        the last
                                         occurs later.    angled AUSI of
                                                          the affected
                                                          hub, whichever
                                                          occurs first.
2...........  Yes.....................  At the next HPT  Thereafter at
                                         engine shop      each HPT
                                         visit, not to    engine shop
                                         exceed 2,800     visit or
                                         FCs since the    before
                                         previous AUSI,   exceeding
                                         or within 100    2,800 FCs from
                                         FCs after the    the last AUSI
                                         effective date   of the
                                         of this AD,      affected hub,
                                         whichever        whichever
                                         occurs later.    occurs first.
------------------------------------------------------------------------

    (3) For Group 1 and Group 2 engines with an affected part listed 
in Table 2 to paragraph (h)(3) of this AD, at the next HPT engine 
shop visit not to exceed the applicable cyclic limit specified in 
Table 2 to paragraph (h)(3) of this AD, or 100 FCs after the 
effective date of the AD, whichever occurs later, except as required 
by paragraphs (h)(6) and (8) of this AD, remove the affected part 
from service and replace with a part eligible for installation.

                         Table 2 to Paragraph (h)(3)--Part Replacement Compliance Times
----------------------------------------------------------------------------------------------------------------
                      AUSI performed prior to
   Engine group      effective date of this AD          Part name             Part No.           Cyclic limit
----------------------------------------------------------------------------------------------------------------
1................  Yes..........................  HPT 1st-stage hub...  30G4201 or 30G6201.  3,800 FCs since
                                                                                              last AUSI.
1................  No...........................  HPT 1st-stage hub...  30G4201 or 30G6201.  3,800 CSN.
1................  Yes..........................  HPT 2nd-stage hub...  30G3902 or 30G5502.  3,800 FCs since
                                                                                              last AUSI or 7,000
                                                                                              CSN, whichever
                                                                                              comes first.

[[Page 21189]]

 
1................  No...........................  HPT 2nd-stage hub...  30G3902 or 30G5502.  3,800 CSN.
2................  Yes..........................  HPT 1st-stage hub...  30G4201 or 30G6201.  2,800 FCs since
                                                                                              last AUSI.
2................  No...........................  HPT 1st-stage hub...  30G4201 or 30G6201.  2,800 CSN.
2................  Yes..........................  HPT 2nd-stage hub...  30G3902 or 30G5502.  2,800 FCs since
                                                                                              last AUSI or 5,000
                                                                                              CSN, whichever
                                                                                              comes first.
2................  No...........................  HPT 2nd-stage hub...  30G3902 or 30G5502.  2,800 CSN.
----------------------------------------------------------------------------------------------------------------

    (4) For Group 1 and Group 2 engines with an affected part listed 
in Table 3 to paragraph (h)(4) of this AD, before exceeding the 
applicable compliance times specified in Table 3 to paragraph (h)(4) 
of this AD, remove the affected part from service and replace with a 
part eligible for installation.

                         Table 3 to Paragraph (h)(4)--Part Replacement Compliance Times
----------------------------------------------------------------------------------------------------------------
    Engine group                  Part name                         Part No.                  Compliance time
----------------------------------------------------------------------------------------------------------------
1 and 2.............  HPC rear hub....................  30G4008.........................  At the next HPC shop
                                                                                           visit or HPT shop
                                                                                           visit, whichever
                                                                                           occurs first after
                                                                                           the effective date of
                                                                                           this AD.
1...................  HPC rear hub....................  30G8208.........................  Before accumulating
                                                                                           7,000 CSN or within
                                                                                           100 FCs after the
                                                                                           effective date of
                                                                                           this AD, whichever
                                                                                           occurs later.
1...................  HPC IBR-7.......................  30G2307 or 30G4407..............  Before accumulating
                                                                                           7,000 CSN or within
                                                                                           100 FCs after the
                                                                                           effective date of
                                                                                           this AD, whichever
                                                                                           occurs later.
1...................  HPC IBR-8.......................  30G5608 or 30G5908 or 30G8908...  Before accumulating
                                                                                           7,000 CSN or within
                                                                                           100 FCs after the
                                                                                           effective date of
                                                                                           this AD, whichever
                                                                                           occurs later.
1...................  HPT 1st-stage hub...............  30G7301.........................  Before accumulating
                                                                                           7,000 CSN or within
                                                                                           100 FCs after the
                                                                                           effective date of
                                                                                           this AD, whichever
                                                                                           occurs later.
1...................  HPT 2nd-stage hub...............  30G6602.........................  Before accumulating
                                                                                           7,000 CSN or within
                                                                                           100 FCs after the
                                                                                           effective date of
                                                                                           this AD, whichever
                                                                                           occurs later.
2...................  HPC rear hub....................  30G8208.........................  Before accumulating
                                                                                           5,000 CSN or within
                                                                                           100 FCs after the
                                                                                           effective date of
                                                                                           this AD, whichever
                                                                                           occurs later.
2...................  HPC IBR-7.......................  30G2307 or 30G4407..............  Before accumulating
                                                                                           5,000 CSN or within
                                                                                           100 FCs after the
                                                                                           effective date of
                                                                                           this AD, whichever
                                                                                           occurs later.
2...................  HPC IBR-8.......................  30G5608 or 30G5908 or 30G8908...  Before accumulating
                                                                                           5,000 CSN or within
                                                                                           100 FCs after the
                                                                                           effective date of
                                                                                           this AD, whichever
                                                                                           occurs later.
2...................  HPT 1st-stage hub...............  30G7301.........................  Before accumulating
                                                                                           5,000 CSN or within
                                                                                           100 FCs after the
                                                                                           effective date of
                                                                                           this AD, whichever
                                                                                           occurs later.
2...................  HPT 2nd-stage hub...............  30G6602.........................  Before accumulating
                                                                                           5,000 CSN or within
                                                                                           100 FCs after the
                                                                                           effective date of
                                                                                           this AD, whichever
                                                                                           occurs later.
----------------------------------------------------------------------------------------------------------------

    (5) For affected parts that have been operated in a Group 1 and 
Group 2 configuration, calculate part replacement and AUSI times 
required by paragraphs (h)(2) through (4) using the note to Table 3 
of the compliance paragraph of PW ASB PW1000G-C-72-00-0224-00A-930A-
D, Issue No: 001 or PW ASB PW1000G-C-72-00-0225-00A-930A-D, Issue 
No: 002, as applicable, which addresses calculating mixed model 
cycles.
    (6) For Group 1 and Group 2 engines with an installed HPT 1st-
stage hub having P/N 30G6201 or an HPT 2nd-stage hub having P/N 
30G5502 and an S/N listed in Tables 1, 2, 3, or 4 of PW SI No. 149F-
23 that has not had an AUSI performed before the effective date of 
this AD, before further flight, remove the affected hub from 
service.
    (7) For Group 1 and Group 2 engines with an installed HPT 1st-
stage hub having P/N 30G7301 or an HPT 2nd-stage hub having P/N 
30G6602 with an S/N listed in Tables 1, 2, 3, or 4 of PW SI No. 
198F-23, dated November 3, 2023 (PW SI No. 198F-23), within 100 FC 
after the effective date of this AD, perform an AUSI of the affected 
hub for cracks in accordance with the Accomplishment Instructions, 
paragraph 1.D.(7)(a) or 1.D.(7)(b) of PW ASB PW1000G-C-72-00-0225-
00A-930A-D, Issue No: 002.
    (8) For Group 1 and Group 2 engines with an installed HPT 1st-
stage hub having P/N 30G6201 or an HPT 2nd-stage hub having P/N 
30G5502 with an S/N listed in Tables 1, 2, 3, or 4 of PW SI No. 
198F-23, within 100 FC after the effective date of this AD, remove 
the hub from service and replace with a part eligible for 
installation.
    (9) If any crack indication is found during any AUSI required by 
this AD, before further flight, remove the affected part from 
service and replace with a part eligible for installation.
    (10) If an affected part has accumulated 100 FCs or less since 
the last AUSI, reinspection is not required provided that the part 
was not damaged during removal from the engine.

(i) Definitions

    (1) For the purposes of this AD, ``Group 1 engines'' are IAE LLC 
Model PW1122G-JM, PW1124G1-JM, PW1124G-JM, PW1127G-JM, PW1127G1-JM, 
PW1127G1A-JM, PW1127G1B-JM, and PW1127GA-JM engines.
    (2) For the purposes of this AD, ``Group 2 engines'' are IAE LLC 
Model PW1129G-JM, PW1130G-JM, PW1133G-JM, PW1133GA-JM, PW1428G-JM, 
PW1428GA-JM, PW1428GH-JM, PW1431G-JM, PW1431GA-JM, and PW1431GH-JM 
engines.
    (3) For the purposes of this AD, an ``HPC engine shop visit'' is 
the induction of an

[[Page 21190]]

engine into the shop for maintenance involving the separation of the 
H-flange.
    (4) For the purposes of this AD, an ``HPT engine shop visit'' is 
the induction of an engine into the shop for maintenance involving 
the separation of the M-flange.
    (5) For the purposes of this AD, a ``part eligible for 
installation'' is:
    (i) An HPC IBR-7 having P/N 30G2307 or 30G4407 that has passed 
the AUSI required by paragraph (h)(1) of this AD or is identified as 
not affected by this AD in paragraph (c)(2) of this AD, or later 
approved P/N.
    (ii) An HPC IBR-8 having P/N 30G5608, 30G5908, or 30G8908 that 
has passed the AUSI required by paragraph (h)(1) of this AD or is 
identified as not affected by this AD in paragraph (c)(2) of this 
AD, or later approved P/N.
    (iii) An HPT 1st-stage hub having P/N 30G7301 that has passed 
the AUSI required by paragraph (h)(2) of this AD or is identified as 
not affected by this AD in paragraph (c)(2) of this AD, or later 
approved P/N.
    (iv) An HPT 2nd-stage hub having P/N 30G6602 that has passed the 
AUSI required by paragraph (h)(2) of this AD or is identified as not 
affected by this AD in paragraph (c)(2) of this AD, or later 
approved P/N.
    (v) An HPC rear hub having P/N 30G8208 and is identified as not 
affected by this AD in paragraph (c)(2) of this AD, or later 
approved P/N.

(j) Credit for Previous Actions

    (1) This paragraph provides credit for the actions specified in 
paragraph (g)(1) and (2) of this AD, if those actions were performed 
before the effective date of this AD using PW Service Bulletin 
PW1000G-C-72-00-0188-00A-930A-D, Issue No: 001, dated September 13, 
2021. This service information is not incorporated by reference in 
this AD.
    (2) This paragraph provides credit for the actions specified in 
paragraph (h)(2) and (6) of this AD, if those actions were performed 
before the effective date of this AD using PW Alert Service Bulletin 
PW ASB PW1000G-C-72-00-0225-00A-930A-D, Issue No: 001, dated 
November 3, 2023. This service information is not incorporated by 
reference in this AD.

(k) 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 (l)(1) of this AD.
    (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) Additional Information

    (1) 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].
    (2) Service information identified in this AD that is not 
incorporated by reference is available at the address specified in 
paragraph (m)(6) of this AD.

(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.
    (3) The following service information was approved for IBR on 
April 11, 2024.
    (i) Pratt & Whitney Alert Service Bulletin PW1000G-C-72-00-0224-
00A-930A-D, Issue No: 001, dated November 3, 2023.
    (ii) Pratt & Whitney Alert Service Bulletin PW1000G-C-72-00-
0225-00A-930A-D, Issue No: 002, dated December 12, 2023.
    (iii) Pratt & Whitney Special Instruction No. 198F-23, dated 
November 3, 2023.
    (iv) Pratt & Whitney Special Instruction No. 222F-23, Revision 
B, dated March 1, 2024.
    (4) The following service information was approved for IBR on 
August 28, 2023 (88 FR 56999, August 22, 2023).
    (i) Pratt & Whitney Special Instruction No. 149F-23, dated 
August 4, 2023.
    (ii) [Reserved]
    (5) The following service information was approved for IBR on 
November 7, 2022 (87 FR 59660, October 3, 2022; corrected October 
24, 2022 (87 FR 64156)).
    (i) Pratt & Whitney Service Bulletin PW1000G-C-72-00-0188-00A-
930A-D, Issue No: 002, dated July 8, 2022.
    (ii) [Reserved]
    (6) For Pratt & Whitney service information that is incorporated 
by reference, contact International Aero Engines, LLC, 400 Main 
Street, East Hartford, CT 06118; phone: (860) 565-0140; email: 
[email protected]; website: connect.prattwhitney.com.
    (7) You may view this service information that is incorporated 
by reference 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.
    (8) 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 March 8, 2024.
Victor Wicklund,
Deputy Director, Compliance & Airworthiness Division, Aircraft 
Certification Service.
[FR Doc. 2024-06419 Filed 3-22-24; 11:15 am]
BILLING CODE 4910-13-P