Document ID: FAA-2022-0587-0001
Agency: faa
Document Type: Proposed Rule
Title: Airworthiness Directives: General Electric Company Turbofan Engines
Posted Date: 2022-06-22T04:00Z

[Federal Register Volume 87, Number 119 (Wednesday, June 22, 2022)]
[Proposed Rules]
[Pages 37247-37249]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2022-13202]

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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2022-0587; Project Identifier AD-2022-00394-E]
RIN 2120-AA64

Airworthiness Directives; General Electric Company Turbofan 
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 General Electric Company (GE) GEnx-2B67/P model turbofan 
engines. This proposed AD was prompted by the detection of an iron 
inclusion in a forging, which may reduce the fatigue life of certain 
low-pressure turbine rotor (LPTR) stage 4 disks and LPTR stage 6 disks. 
This proposed AD would require the removal of certain LPTR stage 4 
disks and LPTR stage 6 disks from service and replacement with parts 
eligible for installation. 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 August 8, 
2022.

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 https://www.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.
    For service information identified in this NPRM, contact General 
Electric Company, 1 Neumann Way, Cincinnati, OH 45215; phone: (513) 
552-3272; email: [email protected]; website: https://www.ge.com. You may view this service information at the

[[Page 37248]]

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.

Examining the AD Docket

    You may examine the AD docket at https://www.regulations.gov by 
searching for and locating Docket No. FAA-2022-0587; 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.

FOR FURTHER INFORMATION CONTACT: Alexei Marqueen, Aviation Safety 
Engineer, ECO Branch, FAA, 1200 District Avenue, Burlington, MA 01803; 
phone: (781) 238-7178; 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-2022-0587; Project Identifier 
AD-2022-00394-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 
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 
https://www.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 
Alexei Marqueen, 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 was notified by the engine manufacturer of the detection of 
an iron inclusion in a forging, which may reduce the fatigue life of 
certain LPTR stage 4 disks and LPTR stage 6 disks. The manufacturer's 
investigation determined that the inclusion is a melt-related defect 
and that, as a result of the inclusion forming in the forging, certain 
LPTR stage 4 disks and LPTR stage 6 disks may have reduced material 
properties and a lower fatigue life capability. Reduced material 
properties may cause premature LPTR stage 4 disk and LPTR stage 6 disk 
fracture, which could result in uncontained debris release. As a result 
of its investigation, the manufacturer published service information 
that specifies procedures for the removal and replacement of certain 
LPTR stage 4 disks and LPTR stage 6 disks installed on GEnx-2B67/P 
model turbofan engines. This condition, if not addressed, could result 
in uncontained debris release, damage to the engine, and damage to 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.

Related Service Information

    The FAA reviewed GE GEnx-2B service bulletin (SB) 72-0448 R00, 
dated February 7, 2022. This SB describes procedures for removing the 
affected LPTR stage 4 disks and LPTR stage 6 disks from service.

Proposed AD Requirements in This NPRM

    This proposed AD would require the removal and replacement of 
certain LPTR stage 4 disks and LPTR stage 6 disks.

Costs of Compliance

    The FAA estimates that this AD, if adopted as proposed, would 
affect 4 engines installed on airplanes of U.S. registry. The FAA 
estimates that the affected disk population on engines installed on 
airplanes of U.S. registry would include three LPTR stage 4 disks and 
one LPTR stage 6 disk.
    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
----------------------------------------------------------------------------------------------------------------
Replace the LPTR stage 4 disk.........  500 work-hours x $85 per        $378,400        $420,900      $1,262,700
                                         hour = $42,500.
Replace the LPTR stage 6 disk.........  500 work-hours x $85 per         208,900         251,400         251,400
                                         hour = $42,500.
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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

[[Page 37249]]

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:

General Electric Company: Docket No. FAA-2022-0587; Project 
Identifier AD-2022-00394-E.

(a) Comments Due Date

    The FAA must receive comments on this airworthiness directive 
(AD) by August 8, 2022.

(b) Affected ADs

    None.

(c) Applicability

    This AD applies to General Electric Company (GE) GEnx-2B67/P 
model turbofan engines with an installed:
    (1) Low-pressure turbine rotor (LPTR) stage 4 disk, part number 
(P/N) 2440M64P01, with serial number (S/N) JHVPD762, JHVPD763, 
JHVPD764, or JHVPD765; or
    (2) LPTR stage 6 disk, P/N 2440M66P01, with S/N JHVVD753 or 
JHVVD754.

(d) Subject

    Joint Aircraft System Component (JASC) Code 7250, Turbine 
Section.

(e) Unsafe Condition

    This AD was prompted by the detection of an iron inclusion in a 
forging, which may reduce the fatigue life of certain LPTR stage 4 
disks and LPTR stage 6 disks. The FAA is issuing this AD to prevent 
fracture and subsequent uncontainment of the LPTR stage 4 disk and 
LPTR stage 6 disk. The unsafe condition, if not addressed, could 
result in uncontained debris 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 the affected LPTR stage 4 disk exceeds 3,000 cycles 
since new (CSN), remove the affected LPTR stage 4 disk from service 
and replace with an LPTR stage 4 disk eligible for installation.
    (2) Before the affected LPTR stage 6 disk exceeds 5,000 CSN, 
remove the affected LPTR stage 6 disk from service and replace with 
an LPTR stage 6 disk eligible for installation.

(h) Definitions

    (1) For the purpose of this AD, an ``LPTR stage 4 disk eligible 
for installation'' is an LPTR stage 4 disk that does not have P/N 
2440M64P01, with S/N JHVPD762, JHVPD763, JHVPD764, or JHVPD765.
    (2) For the purpose of this AD, an ``LPTR stage 6 disk eligible 
for installation'' is an LPTR stage 6 disk that does not have P/N 
2440M66P01, with S/N JHVVD753 or JHVVD754.

(i) Alternative Methods of Compliance (AMOCs)

    (1) The Manager, ECO 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 (j) of this AD and email to: [email protected].
    (2) Before using any approved AMOC, notify your appropriate 
principal inspector, or lacking a principal inspector, the manager 
of the local flight standards district office/certificate holding 
district office.

(j) Related Information

    For more information about this AD, contact Alexei Marqueen, 
Aviation Safety Engineer, ECO Branch, FAA, 1200 District Avenue, 
Burlington, MA 01803; phone: (781) 238-7178; email: 
[email protected].

    Issued on May 16, 2022.
Gaetano A. Sciortino,
Deputy Director for Strategic Initiatives, Compliance & Airworthiness 
Division, Aircraft Certification Service.
[FR Doc. 2022-13202 Filed 6-21-22; 8:45 am]
BILLING CODE 4910-13-P