[Federal Register Volume 88, Number 99 (Tuesday, May 23, 2023)]
[Proposed Rules]
[Pages 32978-32980]
[FR Doc No: 2023-10908]

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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.

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Federal Register / Vol. 88, No. 99 / Tuesday, May 23, 2023 / Proposed
Rules

DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2023-0940; Project Identifier AD-2022-01521-E]
RIN 2120-AA64

Airworthiness Directives; Pratt & Whitney Division Engines

AGENCY: Federal Aviation Administration (FAA), DOT.

ACTION: Notice of proposed rulemaking (NPRM).

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SUMMARY: The FAA proposes to supersede Airworthiness Directive (AD)
2018-21-11, which applies to all Pratt & Whitney Division (PW) Model
PW4074D, PW4077D, PW4084D, PW4090, and PW4090-3 engines with a low-
pressure compressor (LPC) fan hub, part number (P/N) 51B821 or P/N
52B521, installed. AD 2018-21-11 requires performing repetitive eddy
current inspections (ECIs) and fluorescent penetrant inspections (FPIs)
for cracks in certain LPC fan hubs and removing LPC fan hubs from
service that fail any inspection. Since the FAA issued AD 2018-21-11,
the FAA determined that affected LPC fan hub assemblies can meet the
published certificated life limit without the need for the required
repetitive FPI inspections in AD 2018-21-11, and the repetitive ECI
inspections require shortened intervals. Based on a report of another
incident, the FAA determined that the unsafe condition is likely to
exist or develop on additional LPC fan hub assemblies and PW model
engines. This proposed AD would expand the applicability to include
Model PW4074, PW4074D, PW4077, PW4077D, PW4084D, PW4090, and PW4090-3
engines with any part number LPC fan hub assembly installed and would
require performing repetitive ECIs of the LPC fan hub assembly and,
depending on the results of the inspections, removal of the LPC fan hub
assembly from service. The FAA is proposing this AD to address the
unsafe condition on these products.

DATES: The FAA must receive comments on this proposed AD by July 7,
2023.

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:<PHONE_NUMBER>.
     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 by
searching for and locating Docket No. FAA-2023-0940; 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 Division service information
identified in this NPRM, contact Pratt & Whitney Division, 400 Main
Street, East Hartford, CT 06118; phone:<PHONE_NUMBER>; 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<PHONE_NUMBER>.

FOR FURTHER INFORMATION CONTACT: Carol Nguyen, Aviation Safety
Engineer, ECO Branch, FAA, 1200 District Avenue, Burlington, MA 01803;
phone:<PHONE_NUMBER>; 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-2023-0940; Project Identifier
AD-2022-01521-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, ECO Branch, FAA, 1200 District
Avenue, Burlington, MA 01803. 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 2018-21-11, Amendment 39-19469 (83 FR 54663,
October 31, 2018), (``AD 2018-21-11''), for all Pratt & Whitney
Division (PW) PW4074D, PW4077D, PW4084D, PW4090, and PW4090-3 turbofan
engines with low-pressure compressor (LPC) fan hub assembly, part
number (P/N) 51B821 or P/N 52B521, installed. AD 2018-21-11 was
prompted by low-cycle fatigue analysis techniques, updated by the
engine manufacturer, which

indicated certain LPC fan hub assemblies could crack before their
published life limit. AD 2018-21-11 requires performing initial and
repetitive FPI and ECIs of the LPC fan hub assembly and removing the
LPC fan hub assembly from service if it fails any inspection. The
agency issued AD 2018-21-11 to prevent failure of the LPC fan hub
assembly.

Actions Since AD 2018-21-11 Was Issued

    Since the FAA issued AD 2018-21-11, the FAA determined that
affected LPC fan hub assemblies can meet the published certificated
life limit without the need for the required repetitive FPI inspections
in AD 2018-21-11, and the repetitive ECI inspections require shortened
intervals. The FAA also received a report of an uncontained failure of
the fan hub assembly on an Engine Alliance GP7270 engine on an Air
France flight. Investigation of this uncontained failure revealed that,
due to the similarity of design and material processing for the LPC fan
hub assembly, the ECI inspections should be done on all LPC fan hub
assembly part numbers installed on PW Model PW4074, PW4074D, PW4077,
PW4077D, PW4084D, PW4090, and PW4090-3 engines.
    This condition, if not addressed, could result in uncontained
debris release, damage to the engine, and damage to the aircraft.

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 Pratt & Whitney Division Alert Service Bulletin
PW4G-112-A72-362, Revision 1 dated January 20, 2023. This service
information specifies procedures for ECIs of the LPC fan hub assembly
for cracks. This service information also specifies reporting
inspection results to PW.
    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 2018-
21-11. This proposed AD would expand the applicability to include Model
PW4074, PW4074D, PW4077, PW4077D, PW4084D, PW4090, and PW4090-3 engines
with any P/N LPC fan hub assembly installed. This proposed AD would
also require performing repetitive ECIs of the LPC fan hub assembly
and, depending on the results of the inspections, removing the LPC fan
hub assembly from service.

Differences Between This Proposed AD and the Service Information

    Where the service information specifies reporting certain
information to PW, this proposed AD does not include that requirement.

Costs of Compliance

    The FAA estimates that this AD, if adopted as proposed, would
affect 65 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
----------------------------------------------------------------------------------------------------------------
Perform ECI of LPC fan hub          14 work-hours x $85    Not Applicable.......          $1,190         $77,350
 assembly.                           per hour = $1,190.
----------------------------------------------------------------------------------------------------------------

    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 this replacement:

                                               On-Condition Costs
----------------------------------------------------------------------------------------------------------------
                                                                                Cost per
                    Action                                 Labor cost               Parts cost        product
----------------------------------------------------------------------------------------------------------------
Replace LPC fan hub assembly..................  65 work-hours x $85 per hour =        $1,194,000      $1,199,525
                                                 $5,525.
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Authority for This Rulemaking

    Title 49 of the United States Code specifies the FAA's authority to
issue rules on aviation safety. Subtitle I, Section 106, describes the
authority of the FAA Administrator. Subtitle VII, Aviation Programs,
describes in more detail the scope of the Agency's authority.
    The FAA is issuing this rulemaking under the authority described in
Subtitle VII, Part A, Subpart III, Section 44701, General requirements.
Under that section, Congress charges the FAA with promoting safe flight
of civil aircraft in air commerce by prescribing regulations for
practices, methods, and procedures the Administrator finds necessary
for safety in air commerce. This regulation is within the scope of that
authority because it addresses an unsafe condition that is likely to
exist or develop on products identified in this rulemaking action.

Regulatory Findings

    The FAA determined that this proposed AD would not have federalism
implications under Executive Order 13132. This proposed AD would not
have a substantial direct effect on the States, on the relationship
between the national Government and the States, or on the distribution
of power and responsibilities among the various levels of government.
    For the reasons discussed above, I certify 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 2018-21-11, Amendment 39-19469 (83
FR 54663, October 31, 2018); and
0
b. Adding the following new airworthiness directive:

Pratt & Whitney Division: Docket No. FAA-2023-0940; Project
Identifier AD-2022-01521-E.

(a) Comments Due Date

    The FAA must receive comments on this airworthiness directive
(AD) action by July 7, 2023.

(b) Affected ADs

    This AD replaces AD 2018-21-11, Amendment 39-19469 (83 FR 54663,
October 31, 2018); (AD 2018-21-11).

(c) Applicability

    This AD applies to all Pratt & Whitney Division (PW) Model
PW4074, PW4074D, PW4077, PW4077D, PW4084D, PW4090, and PW4090-3
engines.

(d) Subject

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

(e) Unsafe Condition

    This AD was prompted by an updated analysis by the engine
manufacturer, which indicated certain low-pressure compressor (LPC)
fan hubs could crack before their published life limit. We are
issuing this AD to prevent failure of the LPC fan hub. The unsafe
condition, if not addressed, could result in uncontained hub
release, damage to the engine, and damage to the airplane.

(f) Compliance

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

(g) Required Actions

    (1) Before accumulating 550 flight cycles (FC) after the
effective date of this AD, and thereafter at intervals not to exceed
550 FC since the last eddy current inspection (ECI), perform an ECI
of the LPC fan hub assembly, in accordance with the Accomplishment
Instructions, For Engines Installed on Aircraft, paragraph 2., or
For Engines Not Installed on Aircraft, paragraph 3; of PW Alert
Service Bulletin PW4G-112-A72-362, Revision 1 dated January 20, 2023
(ASB PW4G-112-A72-362, Revision 1).
    (2) If a rejectable or reportable indication is found during the
inspections required by paragraph (g)(1) of this AD, before further
flight, replace the LPC fan hub assembly with a part eligible for
installation.

(h) Installation Prohibition

    After the effective date of this AD, do not install an LPC fan
hub assembly on any engine, unless it is a part eligible for
installation as defined in paragraph (j) of this AD.

(i) No Reporting Requirement

    This AD does not require reporting certain information to the
manufacturer as specified in ASB PW4G-112-A72-362, Revision 1.

(j) Definitions

    For the purposes of this AD, a ``part eligible for
installation'' is an affected LPC fan hub assembly that has been
inspected as required by paragraph (g)(1) of this AD and does not
have a rejectable or reportable indication or a LPC fan hub assembly
with zero cycles since new.

(k) Alternative Methods of Compliance (AMOCs)

    (1) The Manager, 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 certification office, send it to the
attention of the person identified in paragraph (l) 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) Related Information

    For more information about this AD, contact Carol Nguyen,
Aviation Safety Engineer, ECO Branch, FAA, 1200 District Avenue;
phone:<PHONE_NUMBER>; email: [email protected].

(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.
    (i) Pratt & Whitney Division Alert Service Bulletin PW4G-112-
A72-362, Revision 1, dated January 20, 2023.
    (ii) [Reserved]
    (3) For service information identified in this AD, contact Pratt
& Whitney Division, 400 Main Street, East Hartford, CT 06118; phone:
(860) 565-0140; email: [email protected]; website:
connect.prattwhitney.com.
    (4) You may view this service information at 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<PHONE_NUMBER>.
    (5) You may view this service information that is incorporated
by reference at the National Archives and Records Administration
(NARA). For information on the availability of this material at
NARA, email: [email protected], or go to: www.archives.gov/federal-register/cfr/ibr-locations.html.

    Issued on May 4, 2023.
Michael Linegang,
Acting Director, Compliance & Airworthiness Division, Aircraft
Certification Service.
[FR Doc. 2023-10908 Filed 5-22-23; 8:45 am]
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