[Federal Register Volume 89, Number 160 (Monday, August 19, 2024)]
[Proposed Rules]
[Pages 67009-67012]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2024-18354]


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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2024-2026; Project Identifier AD-2024-00163-E]
RIN 2120-AA64


Airworthiness Directives; Pratt & Whitney Engines

AGENCY: Federal Aviation Administration (FAA), DOT.

ACTION: Notice of proposed rulemaking (NPRM).

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SUMMARY: The FAA proposes to adopt a new airworthiness directive (AD) 
for certain Pratt & Whitney (PW) Model PW1519G, PW1521G, PW1521GA, 
PW1521G-3, PW1524G, PW1524G-3, PW1525G, PW1525G-3, PW1919G, PW1921G, 
PW1922G, PW1923G, and PW1923G-A engines with a certain high-pressure 
compressor (HPC) 7th-stage axial rotor installed. This proposed AD was 
prompted by an analysis of an event involving an International Aero 
Engines, LLC (IAE LLC) Model PW1127GA-JM engine, which experienced an 
HPC 7th-stage integrally bladed rotor (IBR-7) separation that resulted 
in an aborted takeoff. This proposed AD would require performing 
initial and repetitive angled ultrasonic inspections (AUSI) of certain 
HPC 7th-stage axial rotors for cracks and replacing the HPC 7th-stage 
axial rotors if necessary. The FAA is proposing this AD to address the 
unsafe condition on these products.

DATES: The FAA must receive comments on this proposed AD by October 3, 
2024.

ADDRESSES: You may send comments, using the procedures found in 14 CFR 
11.43 and 11.45, by any of the following methods:
     Federal eRulemaking Portal: Go to regulations.gov. Follow 
the instructions for submitting comments.
     Fax: (202) 493-2251.
     Mail: U.S. Department of Transportation, Docket 
Operations, M-30, West Building Ground Floor, Room W12-140, 1200 New 
Jersey Avenue SE, Washington, DC 20590.
     Hand Delivery: Deliver to Mail address above between 9 
a.m. and 5 p.m., Monday through Friday, except Federal holidays.
    AD Docket: You may examine the AD docket at regulations.gov under 
Docket No. FAA-2024-2026; 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 PW material identified in this proposed AD, contact 
Pratt & Whitney, 400 Main Street, East Hartford, CT 06118; phone: (860) 
565-0140; email: [email protected]; website: 
connect.prattwhitney.com.
     You may view this material at the FAA, Airworthiness 
Products Section, Operational Safety Branch, 1200 District Avenue, 
Burlington, MA 01803. For information on the availability of this 
material at the FAA, call (817) 222-5110.

FOR FURTHER INFORMATION CONTACT: Carol Nguyen, Aviation Safety 
Engineer, FAA, 2200 South 216th Street, Des Moines, WA 98198; phone: 
(781) 238-7655; email: [email protected].

SUPPLEMENTARY INFORMATION:

Comments Invited

    The FAA invites you to send any written relevant data, views, or 
arguments about this proposal. Send your comments to an address listed 
under the ADDRESSES section. Include ``Docket No. FAA-2024-2026; 
Project Identifier AD-2024-00163-E'' at the beginning of your comments. 
The most helpful comments reference a specific portion of the proposal, 
explain the reason for any recommended change, and include supporting 
data. The FAA will consider all comments received by the closing date 
and may revise this proposal because of those comments.
    Except for Confidential Business Information (CBI) as described in 
the following paragraph, and other information as described in 14 CFR 
11.35, the FAA will post all comments received, without change, to 
regulations.gov, including any personal information you provide. The 
agency will also post a report summarizing each substantive verbal 
contact received about this NPRM.

[[Page 67010]]

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

    On December 24, 2022, 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 aborted take-off. 
Following this event, the manufacturer conducted a records review of 
production and field-returned parts and re-evaluated their engineering 
analysis methodology. The new analysis found that the failure of the 
HPC IBR-7 was caused by a nickel powdered metal anomaly, similar in 
nature to an anomaly previously observed, and these parts are 
susceptible to failure much earlier than previously determined. As a 
result, the FAA issued multiple ADs requiring AUSIs for certain 
affected parts, however the overall mitigation plan included several 
actions that were not available when those ADs were published. Since 
that time, PW has developed the AUSI for the HPC 7th-stage axial 
rotors. This condition, if not addressed, could result in uncontained 
HPC 7th-stage axial rotor failure, release of high-energy debris, 
damage to the engine, damage to the airplane, and possible loss of the 
airplane.

FAA's Determination

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

Material Incorporated by Reference Under 1 CFR Part 51

    The FAA reviewed the following material:
     PW Alert Service Bulletin (ASB) PW1000G-A-72-00-0157-00A-
930A-D, Issue No: 002, dated May 22, 2024; and PW ASB PW1000G-A-72-00-
0210-00A-930A-D, Issue No: 002, dated May 22, 2024; which specify 
procedures for performing initial AUSIs on affected HPC 7th-stage axial 
rotors. This material also includes the serial numbers of affected HPC 
7th-stage axial rotors. This material is distinct because it applies to 
different engine models in different configurations.
     PW ASB PW1000G-A-72-00-0158-00B-930A-D, Issue No: 002, 
dated August 1, 2024; and PW ASB PW1000G-A-72-00-0211-00A-930A-D, Issue 
No: 002, dated August 1, 2024; which specify procedures for performing 
repetitive AUSIs on affected HPC 7th-stage axial rotors. This material 
is distinct because it applies to different engine models in different 
configurations.
    This material is reasonably available because the interested 
parties have access to it through their normal course of business or by 
the means identified in ADDRESSES.

Proposed AD Requirements in This NPRM

    This proposed AD would require performing initial and repetitive 
AUSIs of certain HPC 7th-stage axial rotors for cracks and replacement 
if necessary.

Interim Action

    The FAA considers this AD to be an interim action. This 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 121 engines installed on airplanes of U.S. registry.
    The FAA estimates the following costs to comply with this proposed 
AD:

                                                 Estimated Costs
----------------------------------------------------------------------------------------------------------------
                                                                                    Cost per       Cost on U.S.
               Action                        Labor cost           Parts cost        product         operators
----------------------------------------------------------------------------------------------------------------
AUSI of HPC 7th-stage axial rotor...  20 work-hours x $85 per              $0           $1,700         $205,700
                                       hour = $1,700.
----------------------------------------------------------------------------------------------------------------

    The FAA estimates the following costs to do any necessary 
replacements that would be required based on the results of the 
proposed inspection. The agency has no way of determining the number of 
engines that might need these replacements:

                                               On-Condition Costs
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                                                                                                     Cost per
                    Action                                Labor cost               Parts cost        product
----------------------------------------------------------------------------------------------------------------
Replacement of HPC 7th-stage axial rotor.....  1 work-hours x $85 per hour =           $84,640          $84,725
                                                $85.
----------------------------------------------------------------------------------------------------------------

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.

[[Page 67011]]

This regulation is within the scope of that authority because it 
addresses an unsafe condition that is likely to exist or develop on 
products identified in this rulemaking action.

Regulatory Findings

    The FAA determined that this proposed AD would not have federalism 
implications under Executive Order 13132. This proposed AD would not 
have a substantial direct effect on the States, on the relationship 
between the national government and the States, or on the distribution 
of power and responsibilities among the various levels of government.
    For the reasons discussed above, I certify this proposed 
regulation:
    (1) Is not a ``significant regulatory action'' under Executive 
Order 12866,
    (2) Would not affect intrastate aviation in Alaska, and
    (3) Would not have a significant economic impact, positive or 
negative, on a substantial number of small entities under the criteria 
of the Regulatory Flexibility Act.

List of Subjects in 14 CFR Part 39

    Air transportation, Aircraft, Aviation safety, Incorporation by 
reference, Safety.

The Proposed Amendment

    Accordingly, under the authority delegated to me by the 
Administrator, the FAA proposes to amend 14 CFR part 39 as follows:

PART 39--AIRWORTHINESS DIRECTIVES

0
1. The authority citation for part 39 continues to read as follows:

    Authority:  49 U.S.C. 106(g), 40113, 44701.


Sec.  39.13  [Amended]

0
2. The FAA amends Sec.  39.13 by adding the following new airworthiness 
directive:

Pratt & Whitney: Docket No. FAA-2024-2026; Project Identifier AD-
2024-00163-E.

(a) Comments Due Date

    The FAA must receive comments on this airworthiness directive 
(AD) by October 3, 2024.

(b) Affected ADs

    None.

(c) Applicability

    This AD applies to Pratt & Whitney (PW) Model PW1519G, PW1521G, 
PW1521GA, PW1521G-3, PW1524G, PW1524G-3, PW1525G, PW1525G-3, 
PW1919G, PW1921G, PW1922G, PW1923G, and PW1923G-A engines with an 
installed high-pressure compressor (HPC) 7th-stage axial rotor 
having part number (P/N) 30G5307.

(d) Subject

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

(e) Unsafe Condition

    This AD was prompted by an analysis of an event involving an 
International Aero Engines, LLC Model PW1127GA-JM engine, which 
experienced an HPC 7th-stage integrally bladed rotor separation that 
resulted in an aborted takeoff. The FAA is issuing this AD to 
prevent failure of the HPC 7th-stage axial rotor. The unsafe 
condition, if not addressed, could result in uncontained HPC 7th-
stage axial rotor failure, release of high-energy debris, damage to 
the engine, damage to the airplane, and possible loss of the 
airplane.

(f) Compliance

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

(g) Required Actions

    (1) At the next piece-part exposure after the effective date of 
this AD and thereafter at each piece-part exposure, except as 
required by paragraph (g)(2) and (4) of this AD, perform an angled 
ultrasonic inspection (AUSI) of the affected HPC 7th-stage axial 
rotor for cracks in accordance with paragraphs (g)(1)(i) and(ii) of 
this AD, as applicable.
    (i) For Model PW1500G engines: Step 7 of the Accomplishment 
Instructions of PW Alert Service Bulletin (ASB) PW1000G-A-72-00-
0210-00A-930A-D, Issue No: 002, dated May 22, 2024 (PW1000G-A-72-00-
0210-00A-930A-D, Issue No: 002), or step 5.B of the Accomplishment 
Instructions of PW ASB PW1000G-A-72-00-0211-00A-930A-D, Issue No: 
002, dated August 1, 2024.
    (ii) For Model PW1900G engines: Step 7 of the Accomplishment 
Instructions of PW ASB PW1000G-A-72-00-0157-00A-930A-D, Issue No: 
002, dated May 22, 2024 (PW1000G-A-72-00-0157-00A-930A-D, Issue No: 
002), or step 5.B of the Accomplishment Instructions of PW ASB 
PW1000G-A-72-00-0158-00B-930A-D, Issue No: 002, dated August 1, 
2024.
    (2) For engines with an installed HPC 7th-stage axial rotor and 
a serial number listed in Table 1 of PW1000G-A-72-00-0210-00A-930A-
D, Issue No: 002, or Table 1 of PW1000G-A-72-00-0157-00A-930A-D, 
Issue No: 002, that have not had an AUSI performed prior to the 
effective date of this AD, at the next HPC engine shop visit after 
the effective date of this AD, not to exceed 10,000 part cycles 
since new, or within 100 flight cycles (FCs) after the effective 
date of this AD, whichever occurs later, and thereafter at each 
piece-part exposure: perform an AUSI of the HPC 7th-stage axial 
rotor for cracks in accordance with paragraphs (g)(1)(i) and (ii) of 
this AD, as applicable.
    (3) If any crack is found during any inspection required by 
paragraphs (g)(1) or (2) of this AD, before further flight, remove 
the HPC 7th-stage axial rotor from service and replace with a part 
eligible for installation.
    (4) If an HPC 7th-stage axial rotor 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.

(h) Definitions

    For the purposes of this AD:
    (1) ``Model PW1500G'' engines are PW Model PW1519G, PW1521G, 
PW1521GA, PW1521G-3, PW1524G, PW1524G-3, PW1525G, and PW1525G-3 
engines.
    (2) ``Model PW1900G'' engines are PW Model PW1919G, PW1921G, 
PW1922G, PW1923G, and PW1923G-A engines.
    (3) A ``part eligible for installation'' is any of the 
following:
    (i) An HPC 7th-stage axial rotor, P/N 30G5307, that has passed 
the AUSI required by paragraphs (g)(1) or (g)(2) of this AD.
    (ii) An HPC 7th-stage axial rotor, P/N 30G5307, that has a 
Certificate of Conformance that shows compliance with NDIP-1281.
    (iii) An HPC 7th-stage axial rotor that has a later approved P/
N.
    (4) A ``piece-part exposure'' is when the HPC 7th-stage axial 
rotor is disassembled from the rotor assembly.
    (5) An ``HPC engine shop visit'' is when the HPC rotor assembly 
is removed from the HPC module.

(i) Credit for Previous Actions

    This paragraph provides credit for the initial AUSI required by 
paragraphs (g)(1) and (2) of this AD, if those actions were done 
before the effective date of this AD using any of the following:
    (1) PW ASB PW1000G-A-72-00-0157-00A-930A-D, Issue No: 001, dated 
February 15, 2024.
    (2) PW ASB PW1000G-A-72-00-0158-00B-930A-D, Issue No: 001, dated 
February 19, 2024.
    (3) PW ASB PW1000G-A-72-00-0210-00A-930A-D, Issue No: 001, dated 
February 15, 2024.
    (4) PW ASB PW1000G-A-72-00-0211-00A-930A-D, Issue No: 001, dated 
February 19, 2024.

(j) Alternative Methods of Compliance (AMOCs)

    (1) The Manager, AIR-520 Continued Operational Safety Branch, 
FAA, has the authority to approve AMOCs for this AD, if requested 
using the procedures found in 14 CFR 39.19. In accordance with 14 
CFR 39.19, send your request to your principal inspector or local 
Flight Standards District Office, as appropriate. If sending 
information directly to the manager of AIR-520 Continued Operational 
Safety Branch, send it to the attention of the person identified in 
paragraph (k) of this AD and email to: [email protected].
    (2) Before using any approved AMOC, notify your appropriate 
principal inspector, or lacking a principal inspector, the manager 
of the local flight standards district office/certificate holding 
district office.

(k) Additional Information

    For more information about this AD, contact Carol Nguyen, 
Aviation Safety Engineer, FAA, 2200 South 216th Street, Des

[[Page 67012]]

Moines, WA 98198; phone: (781) 238-7655; email: 
[email protected].

(l) Material Incorporated by Reference

    (1) The Director of the Federal Register approved the 
incorporation by reference (IBR) of the material listed in this 
paragraph under 5 U.S.C. 552(a) and 1 CFR part 51.
    (2) You must use this material as applicable to do the actions 
required by this AD, unless the AD specifies otherwise.
    (i) Pratt & Whitney (PW) Alert Service Bulletin (ASB) PW1000G-A-
72-00-0157-00A-930A-D, Issue No: 002, dated May 22, 2024.
    (ii) PW ASB PW1000G-A-72-00-0158-00B-930A-D, Issue No: 002, 
dated August 1, 2024.
    (iii) PW ASB PW1000G-A-72-00-0210-00A-930A-D, Issue No: 002, 
dated May 22, 2024.
    (iv) PW ASB PW1000G-A-72-00-0211-00A-930A-D, Issue No: 002, 
dated August 1, 2024.
    (3) For PW material identified in this AD, contact Pratt & 
Whitney, 400 Main Street, East Hartford, CT 06118; phone: (860) 565-
0140; email: [email protected]; website: 
connect.prattwhitney.com.
    (4) You may view this material at the FAA, Airworthiness 
Products Section, Operational Safety Branch, 1200 District Avenue, 
Burlington, MA 01803. For information on the availability of this 
material at the FAA, call (817) 222-5110.
    (5) You may view this material at the National Archives and 
Records Administration (NARA). For information on the availability 
of this material at NARA, visit www.archives.gov/federal-register/cfr/ibr-locations or email [email protected].

    Issued on August 12, 2024.
Peter A. White,
Deputy Director, Integrated Certificate Management Division, Aircraft 
Certification Service.
[FR Doc. 2024-18354 Filed 8-16-24; 8:45 am]
BILLING CODE 4910-13-P