
[Federal Register Volume 88, Number 248 (Thursday, December 28, 2023)]
[Proposed Rules]
[Pages 89627-89632]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2023-28693]


 ========================================================================
 Proposed Rules
                                                 Federal Register
 ________________________________________________________________________
 
 This section of the FEDERAL REGISTER contains notices to the public of 
 the proposed issuance of rules and regulations. The purpose of these 
 notices is to give interested persons an opportunity to participate in 
 the rule making prior to the adoption of the final rules.
 
 ========================================================================
 

  Federal Register / Vol. 88, No. 248 / Thursday, December 28, 2023 / 
Proposed Rules  

[[Page 89627]]



DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2023-2401; Project Identifier AD-2023-01278-E]
RIN 2120-AA64


Airworthiness Directives; International Aero Engines, LLC Engines

AGENCY: Federal Aviation Administration (FAA), DOT.

ACTION: Notice of proposed rulemaking (NPRM).

-----------------------------------------------------------------------

SUMMARY: The FAA proposes to supersede Airworthiness Directive (AD) 
2022-19-15, which applies to certain International Aero Engines, LLC 
(IAE LLC) Model PW1100G series engines; and AD 2023-16-07, which 
applies to certain IAE LLC Model PW1100G series engines and PW1400G 
series engines. AD 2022-19-15 requires 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 requires 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. Since the FAA issued those two ADs, an investigation 
determined an increased risk of powder metal anomalies for all powder 
metal parts in certain powder metal production campaigns, which are 
susceptible to failure significantly earlier than previously 
determined. This proposed AD would retain the AUSI requirement for 
certain HPT 1st-stage and HPT 2nd-stage hubs from AD 2023-16-07. This 
proposed AD would also require 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 replacement if necessary. This proposed AD 
would also 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 proposing this AD to 
address the unsafe condition on these products.

DATES: The FAA must receive comments on this proposed AD by January 17, 
2024.

ADDRESSES: You may send comments, using the procedures found in 14 CFR 
11.43 and 11.45, by any of the following methods:
     Federal eRulemaking Portal: Go to regulations.gov. Follow 
the instructions for submitting comments.
     Fax: (202) 493-2251.
     Mail: U.S. Department of Transportation, Docket 
Operations, M-30, West Building Ground Floor, Room W12-140, 1200 New 
Jersey Avenue SE, Washington, DC 20590.
     Hand Delivery: Deliver to Mail address above between 9 
a.m. and 5 p.m., Monday through Friday, except Federal holidays.
    AD Docket: You may examine the AD docket at regulations.gov under 
Docket No. FAA-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 NPRM, any comments received, and other 
information. The street address for Docket Operations is listed above.
    Material Incorporated by Reference:
     For Pratt & Whitney (PW) service information identified in 
this NPRM, 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 at the FAA, 
Airworthiness Products Section, Operational Safety Branch, 1200 
District Avenue, Burlington, MA 01803. For information on the 
availability of this material at the FAA, call (817) 222-5110.

FOR FURTHER INFORMATION CONTACT: 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 ADDRESSES. Include ``Docket No. FAA-2023-2401; Project Identifier 
AD-2023-01278-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 amend 
the 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.

Background

    The FAA issued AD 2022-19-15, Amendment 39-22184 (87 FR 59660, 
October 3, 2022; corrected October 24, 2022 (87 FR 64156)) (AD 2022-19-
15),

[[Page 89628]]

for 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 2022-19-15 was prompted by an analysis 
of an event involving an International Aero Engines AG V2533-A5 model 
turbofan engine, which experienced an uncontained failure of an HPT 
1st-stage disk that resulted in high-energy debris penetrating the 
engine cowling. AD 2022-19-15 requires performing an AUSI of the HPT 
1st-stage disk and HPT 2nd-stage disk and, depending on the results of 
the inspections, replacing the HPT 1st-stage disk or HPT 2nd-stage 
disk. The agency issued AD 2022-19-15 to prevent failure of the HPT 
1st-stage disk and HPT 2nd-stage disk.
    Since the FAA issued AD 2022-19-15, an Airbus Model A320neo 
airplane powered by IAE LLC Model PW1127GA-JM engines experienced a 
failure of the HPC IBR-7 that resulted in an engine shutdown and an 
aborted take-off. Following this event, the manufacturer conducted a 
records review of production and field-returned parts and then re-
evaluated their engineering analysis methodology. The new analysis 
identified HPT 1st-stage hubs and HPT 2nd-stage hubs that are 
susceptible to failure significantly earlier than previously 
determined. On August 4, 2023, PW issued service information with 
procedures for an AUSI to detect cracks and prevent premature failure. 
The manufacturer's updated analysis also identified PW1400G series 
engines that contain HPT 1st-stage hubs and HPT 2nd-stage hubs that are 
also subject to the unsafe condition. The FAA determined that the new 
service information necessitated action much earlier than the 
compliance time mandated in AD 2022-19-15 and that the additional 
engines should also be subject to these actions. As a result, the FAA 
issued AD 2023-16-07, Amendment 39-22526 (88 FR 56999, August 22, 2023) 
(AD 2023-16-07) for 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. AD 2023-16-07 
requires performing 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, depending on the results of the 
inspections, replacing the HPT 1st-stage hub or HPT 2nd-stage hub, 
which was terminating action for the requirements of AD 2022-19-15. The 
FAA issued AD 2023-16-07 to prevent failure of the HPT 1st-stage hub 
and HPT 2nd-stage hub.

Actions Since the Previous ADs Were Issued

    Since the FAA issued AD 2023-16-07, additional manufacturer 
analysis found that the failure of the HPC IBR-7 was caused by a powder 
metal anomaly, similar in nature to the anomalies outlined in AD 2022-
19-15. The analysis also concluded that there is an increased risk of 
failure for additional powder metal parts in certain powder metal 
production campaigns, specifically 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.

Previous NPRM

    To address the unsafe condition, the FAA issued an NPRM (Docket No. 
FAA-2023-2237; Project Identifier AD-2023-01057-E) 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, since that NPRM 
was issued, the FAA has received information from PW that an error was 
inadvertently included in the NPRM compliance times for some of the HPT 
1st-stage and 2nd-stage hubs, which would have required removal 
significantly later than necessary. Because the removal timeframe 
needed to be shortened, the FAA determined it is necessary to withdraw 
the NPRM and issue a new NPRM for the unsafe condition with the correct 
compliance times.
    The FAA received comments on the previous NPRM (Docket No. FAA-
2023-2237; Project Identifier AD-2023-01057-E), which will be copied to 
Docket No. FAA-2023-2401 and addressed in the final rule.
    Since the requirements in this proposed AD are similar to those 
proposed in the withdrawn NPRM, and because the comment period on the 
withdrawn NPRM was 30 days, we have good cause to make the comment 
period for this proposed AD 20 days.

FAA's Determination

    The FAA is issuing this NPRM after determining that the unsafe 
condition described previously is likely to exist or develop on other 
products of the same type design.

Related Service Information Under 1 CFR Part 51

    The FAA reviewed the following service information:
     PW Alert Service Bulletin (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: 001, 
dated November 3, 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 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;
     PW Special Instruction (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; and
    This service information is reasonably available because the 
interested parties have access to it through their normal course of 
business or by the means identified in ADDRESSES.

Proposed AD Requirements in This NPRM

    This proposed AD would retain none of the requirements of AD 2022-
19-15, however, it would retain certain requirements of AD 2023-16-07. 
This proposed AD would require performing an AUSI of the HPT 1st-stage 
hub and HPT 2nd-stage hub and replacing as necessary. This proposed AD 
would also require performing an AUSI of the HPC IBR-7 and HPC IBR-8 
for cracks and replacing as necessary. This proposed AD would also 
require accelerated replacement of the HPC IBR-7, HPC IBR-8, HPC rear 
hub, HPT

[[Page 89629]]

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.

Interim Action

    The FAA considers this proposed 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.

Costs of Compliance

    The FAA estimates that this AD, if adopted as proposed, would 
affect 430 engines installed on airplanes of U.S. registry. The FAA 
estimates that 366 engines would need replacement of the HPT 1st-stage 
hub; 351 engines would need replacement of the HPT 2nd-stage hub; 408 
engines would need replacement of the HPC IBR-7; 368 engines would need 
replacement of the HPC IBR-8; 283 engines would need replacement of the 
HPC rear hub; and 206 engines would need replacement of the HPT 1st-
stage air seal, HPT 1st-stage blade retaining plate, HPT 2nd-stage 
blade retaining plate, and HPT 2nd-stage rear seal.
    The FAA estimates the following costs to comply with this proposed 
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.
Replace HPT 1st-stage air seal, HPT    20 work-hours x $85 per              35,000       36,700        7,560,200
 1st-stage blade retaining plate, HPT   hour = $1,700.
 2nd-stage blade retaining plate, and
 HPT 2nd-stage rear seal.
----------------------------------------------------------------------------------------------------------------

    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 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 that the 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:
0
a. Removing Airworthiness Directive 2022-19-15, Amendment 39-22184 (87 
FR 64156, October 24, 2022; corrected October 24, 20 (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:

International Aero Engines, LLC: Docket No. FAA-2023-2401; Project 
Identifier AD-2023-01278-E.

(a) Comments Due Date

    The FAA must receive comments on this airworthiness directive 
(AD) by January 17, 2024.

(b) Affected ADs

    (1) This AD replaces AD 2022-19-15, Amendment 39-22184 (87 FR 
64156, October 24, 2022; corrected October 24, 20 (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

    This AD applies to International Aero Engines, LLC (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.

[[Page 89630]]

(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 a high-
pressure compressor (HPC) 7th-stage integrally bladed rotor (IBR-7) 
that resulted in an engine shutdown and aborted takeoff. The FAA is 
issuing this AD to failure of the high-pressure turbine (HPT) 1st-
stage hub, HPT 2nd-stage hub, HPC IBR-7, and HPC 8th-stage 
integrally bladed rotor (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 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 002.

(h) New Required Actions

    (1) For Group 1 and Group 2 engines with an installed HPC IBR-7 
having part number (P/N) 30G2307 or 30G4407 or an installed 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.
    (2) 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, 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)(6) 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: 001, dated November 3, 2023 (PW ASB PW1000G-C-
72-00-0225-00A-930A-D). 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 interval
                              AD
----------------------------------------------------------------------------------------------------------------
1................  No.....................  Before accumulating 3,800 cycles   Thereafter at each HPT engine
                                             since new (CSN) or within 100      shop visit or before exceeding
                                             flight cycles (FCs) after the      3,800 FCs from the last AUSI of
                                             effective date of this AD,         the affected hub, whichever
                                             whichever occurs later.            occurs first.
1................  Yes....................  At the next HPT engine shop        Thereafter at each HPT engine
                                             visit, not to exceed 3,800 FCs     shop visit or before exceeding
                                             since the previous AUSI, or        3,800 FCs from the last AUSI of
                                             within 100 FCs after the           the affected hub, whichever
                                             effective date of this AD,         occurs first.
                                             whichever occurs later.
2................  No.....................  Before accumulating 2,800 CSN or   Thereafter at each HPT engine
                                             within 100 FCs after the           shop visit or before exceeding
                                             effective date of this AD,         2,800 FCs from the last angled
                                             whichever occurs later.            AUSI of the affected hub,
                                                                                whichever occurs first.
2................  Yes....................  At the next HPT engine shop        Thereafter at each HPT engine
                                             visit, not to exceed 2,800 FCs     shop visit or before exceeding
                                             since the previous AUSI, or        2,800 FCs from the last AUSI of
                                             within 100 FCs after the           the affected hub, whichever
                                             effective date of this AD,         occurs first.
                                             whichever occurs later.
----------------------------------------------------------------------------------------------------------------

    (3) For Group 1 and Group 2 engines with an installed 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)(5) and (7) 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
    Engine group     to effective date of        Part name            Part number             Cyclic limit
                            this AD
----------------------------------------------------------------------------------------------------------------
1..................  Yes.................  HPT 1st-stage hub...  30G4201 or 30G6201..  3,800 FCs since last
                                                                                        AUSI.
                     No..................  HPT 1st-stage hub...  30G4201 or 30G6201..  3,800 CSN.
                     Yes.................  HPT 2nd-stage hub...  30G3902 or 30G5502..  3,800 FCs since last AUSI
                                                                                        or 7,000 CSN whichever
                                                                                        comes first.
                     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.
                     No..................  HPT 1st-stage hub...  30G4201 or 30G6201..  2,800 CSN.
                     Yes.................  HPT 2nd-stage hub...  30G3902 or 30G5502..  2,800 FCs since last AUSI
                                                                                        or 5,000 CSN whichever
                                                                                        comes first.
                     No..................  HPT 2nd-stage hub...  30G3902 or 30G5502..  2,800 CSN.
----------------------------------------------------------------------------------------------------------------


[[Page 89631]]

    (4) For Group 1 and Group 2 engines with an installed 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 number                    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 and 2..............  HPT 1st-stage front air   30G3994 or 30G4674.....  At the next HPT engine shop visit.
                        seal.
                       HPT 2nd-stage rear air    30G2452................
                        seal.
                       HPT 1st-stage blade       30G2446................
                        retaining plate.
                       HPT 2nd-stage blade       30G2447................
                        retaining plate.
1....................  HPC rear hub............  30G8208................  Before accumulating 7,000 CSN or
                                                                           within 100 FCs after the effective
                                                                           date of this AD, whichever occurs
                                                                           later.
                       HPC IBR-7...............  30G2307 or 30G4407.....
                       HPC IBR-8...............  30G5608 or 30G5908 or
                                                  30G8908.
                       HPT 1st-stage hub.......  30G7301................
                       HPT 2nd-stage hub.......  30G6602................
2....................  HPC rear hub............  30G8208................  Before accumulating 5,000 CSN or
                                                                           within 100 FCs after the effective
                                                                           date of this AD, whichever occurs
                                                                           later.
                       HPC IBR-7...............  30G2307 or 30G4407.....
                       HPC IBR-8...............  30G5608 or 30G5908 or
                                                  30G8908.
                       HPT 1st-stage hub.......  30G7301................
                       HPT 2nd-stage hub.......  30G6602................
----------------------------------------------------------------------------------------------------------------

    (5) 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.
    (6) 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, 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.
    (7) 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, dated November 3, 2023, within 100 FC after the effective 
date of this AD, remove the hub from service and replace with a part 
eligible for installation.
    (8) If any crack is found during any inspection required by this 
AD, before further flight, remove the affected part from service and 
replace with a part eligible for installation.
    (9) 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, 
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 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 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 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 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 later approved P/N.
    (v) An HPC rear hub, P/N 30G8208 or later approved P/N.
    (vi) An HPT 1st-stage front air seal, P/N 30G4617 or later 
approved P/N.
    (vii) An HPT 2nd-stage rear air seal, P/N 30G4811 or later 
approved P/N.
    (viii) An HPT 1st-stage blade retaining plate, P/N 30G6059, 
31G0018 or later approved P/N.

(j) Credit for Previous Actions

    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.

(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

[[Page 89632]]

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 addresses specified in 
paragraphs (m)(6) and (7) 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 
[DATE 35 DAYS AFTER PUBLICATION OF THE FINAL RULE].
    (i) Pratt & Whitney (PW) Alert Service Bulletin PW1000G-C-72-00-
0224-00A-930A-D, Issue No: 001, dated November 3, 2023.
    (ii) PW Alert Service Bulletin PW1000G-C-72-00-0225-00A-930A-D, 
Issue No: 001, dated November 3, 2023.
    (iii) PW Special Instruction NO. 198F-23, dated November 3, 
2023.
    (4) The following service information was approved for IBR on 
August 28, 2023 (88 FR 56999, August 22, 2023).
    (i) PW 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) PW Service Bulletin PW1000G-C-72-00-0188-00A-930A-D, Issue 
No: 002, dated July 8, 2022.
    (ii) [Reserved]
    (6) For PW service information identified in this AD, 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 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 December 21, 2023.
Caitlin Locke,
Director, Compliance & Airworthiness Division, Aircraft Certification 
Service.
[FR Doc. 2023-28693 Filed 12-22-23; 4:15 pm]
BILLING CODE 4910-13-P


