Document ID: FAA-2022-0587-0003
Agency: faa
Document Type: Rule
Title: Airworthiness Directives: General Electric Company Turbofan Engines
Posted Date: 2022-09-20T04:00Z

[Federal Register Volume 87, Number 181 (Tuesday, September 20, 2022)]
[Rules and Regulations]
[Pages 57377-57379]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2022-20289]

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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; 
Amendment 39-22170; AD 2022-19-01]
RIN 2120-AA64

Airworthiness Directives; General Electric Company Turbofan 
Engines

AGENCY: Federal Aviation Administration (FAA), DOT.

ACTION: Final rule.

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SUMMARY: The FAA is adopting a new airworthiness directive (AD) for 
certain General Electric Company (GE) GEnx-2B67/P model turbofan 
engines. This 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 AD 
requires 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 issuing this AD to address the unsafe 
condition on these products.

DATES: This AD is effective October 25, 2022.

ADDRESSES: AD Docket: You may examine the AD docket at 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 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.

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: 

Background

    The FAA issued a notice of proposed rulemaking (NPRM) to amend 14 
CFR part 39 by adding an AD that would apply to certain GE GEnx-2B67/P 
model turbofan engines with an affected LPTR stage 4 disk or LPTR stage 
6 disk installed, identified by part number and serial number. The NPRM 
published in the Federal Register on June 22, 2022 (87 FR 37247). The 
NPRM was prompted by the engine manufacturer notifying the FAA 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. In the NPRM, the FAA proposed to 
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 issuing this AD to address the unsafe 
condition on these products.

Discussion of Final Airworthiness Directive

Comments

    The FAA received one comment, from The Boeing Company (Boeing). 
Boeing concurred with the contents of the NPRM.

Conclusion

    The FAA reviewed the relevant data, considered the comment 
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

[[Page 57378]]

changes, this AD is adopted as proposed in the NPRM.

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.

Costs of Compliance

    The FAA estimates that this AD affects 4 engines installed on 
airplanes of U.S. registry.
    The FAA estimates the following costs to comply with this 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.
----------------------------------------------------------------------------------------------------------------

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

    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 adding the following new airworthiness 
directive:

2022-19-01 General Electric Company: Amendment 39-22170; Docket No. 
FAA-2022-0587; Project Identifier AD-2022-00394-E.

(a) Effective Date

    This airworthiness directive (AD) is effective October 25, 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].

(k) Material Incorporated by Reference

    None.

[[Page 57379]]

    Issued on August 29, 2022.
Ross Landes,
Deputy Director for Regulatory Operations, Compliance & Airworthiness 
Division, Aircraft Certification Service.
[FR Doc. 2022-20289 Filed 9-19-22; 8:45 am]
BILLING CODE 4910-13-P