Airworthiness Directives; General Electric Company Turbofan Engines, 56217-56220 [2021-21905]

Download as PDF 56217 Proposed Rules Federal Register Vol. 86, No. 193 Friday, October 8, 2021 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. DEPARTMENT OF TRANSPORTATION Federal Aviation Administration Examining the AD Docket 14 CFR Part 39 [Docket No. FAA–2021–0869; Project Identifier AD–2021–00176–E] RIN 2120–AA64 Airworthiness Directives; General Electric Company Turbofan Engines Federal Aviation Administration (FAA), DOT. ACTION: Notice of proposed rulemaking (NPRM). AGENCY: The FAA proposes to adopt a new airworthiness directive (AD) for certain General Electric Company (GE) CF34–8C and CF34–8E model turbofan engines. This proposed AD was prompted by a report of a quality escape during the manufacturing of a highpressure turbine (HPT) rotor stage 1 disk. This proposed AD would require removing the HPT rotor stage 1 disk from service and replacing the HPT rotor stage 1 disk with a part eligible for installation. The FAA is proposing this AD to the unsafe condition on these products. DATES: The FAA must receive comments on this proposed AD by November 22, 2021. 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 jspears on DSK121TN23PROD with PROPOSALS1 SUMMARY: VerDate Sep<11>2014 16:42 Oct 07, 2021 Company, 1 Neumann Way, Cincinnati, OH 45215; phone: (513) 552–3272; email: aviation.fleetsupport@ae.ge.com; website: https://www.ge.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 (781) 238– 7759. Jkt 256001 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 Scott Stevenson, 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. You may examine the AD docket at https://www.regulations.gov by searching for and locating Docket No. FAA–2021–0869; 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: Scott Stevenson, Aviation Safety Engineer, ECO Branch, FAA, 1200 District Avenue, Burlington, MA 01803; Background phone: (781) 238–7132; fax: (781) 238– The FAA was notified by GE of a 7199; email: Scott.M.Stevenson@faa.gov. quality escape that occurred during the SUPPLEMENTARY INFORMATION: manufacturing of an HPT rotor stage 1 Comments Invited disk. The quality escape occurred at a supplier that began production in The FAA invites you to send any August 2019. On November 25, 2019, written relevant data, views, or the supplier discovered tool gouges at arguments about this proposal. Send the forward chamfer of the air holes in your comments to an address listed an HPT rotor stage 1 disk. These gouges under ADDRESSES. Include ‘‘Docket No. FAA–2021–0869; Project Identifier AD– can reduce the life of the HPT rotor 2021–00176–E’’ at the beginning of your stage 1 disk. This condition, if not addressed, could result in uncontained comments. The most helpful comments disk release, damage to the engine, and reference a specific portion of the proposal, explain the reason for any damage to the airplane. recommended change, and include supporting data. The FAA will consider FAA’s Determination all comments received by the closing The FAA is issuing this NPRM after date and may amend this proposal determining that the unsafe condition because of those comments. described previously is likely to exist or Except for Confidential Business develop on other products of the same Information (CBI) as described in the type design. following paragraph, and other Related Service Information information as described in 14 CFR 11.35, the FAA will post all comments The FAA reviewed GE CF34–8C Alert received, without change, to https:// Service Bulletin (ASB) 72–A0344 R01 www.regulations.gov, including any and GE CF34–8E ASB 72–A0228 R01, personal information you provide. The both dated December 19, 2019. The agency will also post a report ASBs describe procedures for removing summarizing each substantive verbal the HPT rotor stage 1 disk. The FAA contact received about this NPRM. also reviewed GE Repair Document RD Confidential Business Information #150–1811–P1, dated March 17, 2020. This document describes procedures for CBI is commercial or financial information that is both customarily and repairing the HPT rotor stage 1 disk. PO 00000 Frm 00001 Fmt 4702 Sfmt 4702 E:\FR\FM\08OCP1.SGM 08OCP1 56218 Federal Register / Vol. 86, No. 193 / Friday, October 8, 2021 / Proposed Rules Proposed AD Requirements in This NPRM This proposed AD would require removing a certain HPT rotor stage 1 disk from service and replacing the HPT rotor stage 1 disk with a part eligible for installation. Differences Between This Proposed AD and the Service Information The ASBs instruct operators to perform a visual inspection of the HPT rotor stage 1 disk and re-mark the HPT rotor stage 1 disk, while this proposed AD would not mandate visual inspection or re-marking. The ASBs also instruct operators to perform an inspection of the removed HPT rotor stage 1 disk and send it to an authorized service center for repair, while this proposed AD would require removal of the HPT rotor stage 1 disk from service and replacement with a part eligible for installation. Costs of Compliance The FAA estimates that this AD, if adopted as proposed, would affect 23 engines installed on airplanes of U.S. registry. The FAA estimates the following costs to comply with this proposed AD: ESTIMATED COSTS Action Labor cost Remove and replace HPT rotor stage 1 disk 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 jspears on DSK121TN23PROD with PROPOSALS1 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 VerDate Sep<11>2014 16:42 Oct 07, 2021 Jkt 256001 Parts cost 812 work-hours × $85 per hour = $69,020 .... 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 $258,100 § 39.13 Fmt 4702 Sfmt 4702 $7,523,760 [Amended] 2. The FAA amends § 39.13 by adding the following new airworthiness directive: ■ General Electric Company: Docket No. FAA– 2021–0869; Project Identifier AD–2021– 00176–E. (a) Comments Due Date The FAA must receive comments on this airworthiness directive (AD) by November 22, 2021. (b) Affected ADs None. (c) Applicability This AD applies to General Electric Company (GE) CF34–8C5, CF34–8C5B1, CF34–8E2, CF34–8E2A1, CF34–8E5, CF34– 8E5A1, CF34–8E5A2, CF34–8E6, and CF34– 8E6A1 model turbofan engines with an installed high-pressure turbine (HPT) rotor stage 1 disk, part number (P/N) 4125T22P04, and a serial number (S/N) listed in Figure 1 or Figure 2 to paragraph (c) of this AD. BILLING CODE 4910–13–P 1. The authority citation for part 39 continues to read as follows: Frm 00002 $327,120 Cost on U.S. operators Authority: 49 U.S.C. 106(g), 40113, 44701. ■ PO 00000 Cost per product E:\FR\FM\08OCP1.SGM 08OCP1 Federal Register / Vol. 86, No. 193 / Friday, October 8, 2021 / Proposed Rules Joint Aircraft System Component (JASC) Code 7250, Turbine Section. addressed, could result in uncontained disk release, damage to the engine, and damage to the airplane. (e) Unsafe Condition (f) Compliance This AD was prompted by a report of a quality escape during the manufacturing of an HPT rotor stage 1 disk. The FAA is issuing this AD to prevent failure of the HPT rotor stage 1 disk. The unsafe condition, if not Comply with this AD within the compliance times specified, unless already done. VerDate Sep<11>2014 16:42 Oct 07, 2021 Jkt 256001 PO 00000 Frm 00003 Fmt 4702 Sfmt 4702 (g) Required Actions For all affected engines, at the next engine shop visit or before the HPT rotor stage 1 disk accumulates 7,600 cycles since new, whichever occurs first after the effective date of this AD, remove the HPT rotor stage 1 disk from service and replace with a part eligible for installation. E:\FR\FM\08OCP1.SGM 08OCP1 EP08OC21.021</GPH> EP08OC21.022</GPH> jspears on DSK121TN23PROD with PROPOSALS1 (d) Subject 56219 56220 Federal Register / Vol. 86, No. 193 / Friday, October 8, 2021 / Proposed Rules (h) Definitions DEPARTMENT OF TRANSPORTATION For the purpose of this AD: (1) An ‘‘engine shop visit’’ is the induction of an engine into the shop for maintenance involving the separation of pairs of major mating engine flanges, except that the separation of engine flanges solely for the purposes of transportation without subsequent engine maintenance does not constitute an engine shop visit. (2) A ‘‘part eligible for installation’’ is an HPT rotor stage 1 disk that is not listed in Figure 1 or Figure 2 to paragraph (c) of this AD or an HPT rotor stage 1 disk that has been repaired using an FAA-approved repair. Note 1 to paragraph (h)(2): Guidance for repairing the HPT rotor stage 1 disk can be found in GE Repair Document RD # 150– 1811–P1, dated March 17, 2020. (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)(1) of this AD. Information may be emailed to: ANE-ADAMOC@faa.gov. (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 jspears on DSK121TN23PROD with PROPOSALS1 (1) For more information about this AD, contact Scott Stevenson, Aviation Safety Engineer, ECO Branch, FAA, 1200 District Avenue, Burlington, MA 01803; phone: (781) 238–7132; fax: (781) 238–7759; email: Scott.M.Stevenson@faa.gov. (2) For service information identified in this AD, contact General Electric Company, 1 Neumann Way, Cincinnati, OH 45215; phone: (513) 552–3272; email: aviation.fleetsupport@ae.ge.com; website: https://www.ge.com. You may view this referenced service information at the FAA, Airworthiness Products Section, 1200 District Avenue, Burlington, MA 01803. For information on the availability of this material at the FAA, call (781) 238–7759. Issued on September 30, 2021. Lance T. Gant, Director, Compliance & Airworthiness Division, Aircraft Certification Service. [FR Doc. 2021–21905 Filed 10–7–21; 8:45 am] BILLING CODE 4910–13–C VerDate Sep<11>2014 16:42 Oct 07, 2021 Jkt 256001 Federal Aviation Administration 14 CFR Part 39 [Docket No. FAA–2021–0872; Project Identifier MCAI–2021–00312–R] RIN 2120–AA64 Airworthiness Directives; Airbus Helicopters Federal Aviation Administration (FAA), DOT. ACTION: Notice of proposed rulemaking (NPRM). AGENCY: The FAA proposes to supersede Airworthiness Directive (AD) 2020–11–05, which applies to all Airbus Helicopters Model EC120B helicopters. AD 2020–11–05 requires repetitive inspections of the tail rotor (TR) hub body for cracks and applicable corrective actions if necessary, and repetitive replacement of the attachment bolts, washers, and nuts of the TR hub body. This proposed AD would retain certain requirements of AD 2020–11–05, add repetitive inspections, require additional corrective actions, and update applicable service information. The FAA is proposing this AD to address the unsafe condition on these products. SUMMARY: The FAA must receive comments on this proposed AD by November 22, 2021. 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 Airbus Helicopters, 2701 North Forum Drive, Grand Prairie, TX 75052; telephone (972) 641–0000 or (800) 232–0323; fax (972) 641–3775; or at https://www.airbus.com/helicopters/ services/technical-support.html. You may view this service information at the FAA, Office of the Regional Counsel, Southwest Region, 10101 Hillwood Pkwy., Room 6N–321, Fort Worth, TX 76177. For information on the DATES: PO 00000 Frm 00004 Fmt 4702 Sfmt 4702 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–2021–0872; 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, the European Union Aviation Safety Agency (EASA) AD, any comments received, and other information. The street address for Docket Operations is listed above. FOR FURTHER INFORMATION CONTACT: Andrea Jimenez, Aerospace Engineer, COS Program Management Section, Operational Safety Branch, Compliance & Airworthiness Division, FAA, 1600 Stewart Ave., Suite 410, Westbury, NY 11590; telephone (516) 228–7330; email andrea.jimenez@faa.gov. 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–2021–0872; Project Identifier MCAI–2021–00312–R’’ 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 E:\FR\FM\08OCP1.SGM 08OCP1

Agencies

[Federal Register Volume 86, Number 193 (Friday, October 8, 2021)]
[Proposed Rules]
[Pages 56217-56220]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2021-21905]


========================================================================
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. 86, No. 193 / Friday, October 8, 2021 / 
Proposed Rules

[[Page 56217]]



DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2021-0869; Project Identifier AD-2021-00176-E]
RIN 2120-AA64


Airworthiness Directives; General Electric Company Turbofan 
Engines

AGENCY: Federal Aviation Administration (FAA), DOT.

ACTION: Notice of proposed rulemaking (NPRM).

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

SUMMARY: The FAA proposes to adopt a new airworthiness directive (AD) 
for certain General Electric Company (GE) CF34-8C and CF34-8E model 
turbofan engines. This proposed AD was prompted by a report of a 
quality escape during the manufacturing of a high-pressure turbine 
(HPT) rotor stage 1 disk. This proposed AD would require removing the 
HPT rotor stage 1 disk from service and replacing the HPT rotor stage 1 
disk with a part eligible for installation. The FAA is proposing this 
AD to the unsafe condition on these products.

DATES: The FAA must receive comments on this proposed AD by November 
22, 2021.

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 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 (781) 238-7759.

Examining the AD Docket

    You may examine the AD docket at https://www.regulations.gov by 
searching for and locating Docket No. FAA-2021-0869; 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: Scott Stevenson, Aviation Safety 
Engineer, ECO Branch, FAA, 1200 District Avenue, Burlington, MA 01803; 
phone: (781) 238-7132; fax: (781) 238-7199; 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-2021-0869; Project Identifier 
AD-2021-00176-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 Scott 
Stevenson, 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 GE of a quality escape that occurred during 
the manufacturing of an HPT rotor stage 1 disk. The quality escape 
occurred at a supplier that began production in August 2019. On 
November 25, 2019, the supplier discovered tool gouges at the forward 
chamfer of the air holes in an HPT rotor stage 1 disk. These gouges can 
reduce the life of the HPT rotor stage 1 disk. This condition, if not 
addressed, could result in uncontained disk 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 CF34-8C Alert Service Bulletin (ASB) 72-A0344 
R01 and GE CF34-8E ASB 72-A0228 R01, both dated December 19, 2019. The 
ASBs describe procedures for removing the HPT rotor stage 1 disk. The 
FAA also reviewed GE Repair Document RD #150-1811-P1, dated March 17, 
2020. This document describes procedures for repairing the HPT rotor 
stage 1 disk.

[[Page 56218]]

Proposed AD Requirements in This NPRM

    This proposed AD would require removing a certain HPT rotor stage 1 
disk from service and replacing the HPT rotor stage 1 disk with a part 
eligible for installation.

Differences Between This Proposed AD and the Service Information

    The ASBs instruct operators to perform a visual inspection of the 
HPT rotor stage 1 disk and re-mark the HPT rotor stage 1 disk, while 
this proposed AD would not mandate visual inspection or re-marking. The 
ASBs also instruct operators to perform an inspection of the removed 
HPT rotor stage 1 disk and send it to an authorized service center for 
repair, while this proposed AD would require removal of the HPT rotor 
stage 1 disk from service and replacement with a part eligible for 
installation.

Costs of Compliance

    The FAA estimates that this AD, if adopted as proposed, would 
affect 23 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
----------------------------------------------------------------------------------------------------------------
Remove and replace HPT rotor stage 1    812 work-hours x $85 per        $258,100        $327,120      $7,523,760
 disk.                                   hour = $69,020.
----------------------------------------------------------------------------------------------------------------

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 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-2021-0869; Project 
Identifier AD-2021-00176-E.

(a) Comments Due Date

    The FAA must receive comments on this airworthiness directive 
(AD) by November 22, 2021.

(b) Affected ADs

    None.

(c) Applicability

    This AD applies to General Electric Company (GE) CF34-8C5, CF34-
8C5B1, CF34-8E2, CF34-8E2A1, CF34-8E5, CF34-8E5A1, CF34-8E5A2, CF34-
8E6, and CF34-8E6A1 model turbofan engines with an installed high-
pressure turbine (HPT) rotor stage 1 disk, part number (P/N) 
4125T22P04, and a serial number (S/N) listed in Figure 1 or Figure 2 
to paragraph (c) of this AD.
BILLING CODE 4910-13-P

[[Page 56219]]

[GRAPHIC] [TIFF OMITTED] TP08OC21.021

[GRAPHIC] [TIFF OMITTED] TP08OC21.022

(d) Subject

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

(e) Unsafe Condition

    This AD was prompted by a report of a quality escape during the 
manufacturing of an HPT rotor stage 1 disk. The FAA is issuing this 
AD to prevent failure of the HPT rotor stage 1 disk. The unsafe 
condition, if not addressed, could result in uncontained disk 
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

    For all affected engines, at the next engine shop visit or 
before the HPT rotor stage 1 disk accumulates 7,600 cycles since 
new, whichever occurs first after the effective date of this AD, 
remove the HPT rotor stage 1 disk from service and replace with a 
part eligible for installation.

[[Page 56220]]

(h) Definitions

    For the purpose of this AD:
    (1) An ``engine shop visit'' is the induction of an engine into 
the shop for maintenance involving the separation of pairs of major 
mating engine flanges, except that the separation of engine flanges 
solely for the purposes of transportation without subsequent engine 
maintenance does not constitute an engine shop visit.
    (2) A ``part eligible for installation'' is an HPT rotor stage 1 
disk that is not listed in Figure 1 or Figure 2 to paragraph (c) of 
this AD or an HPT rotor stage 1 disk that has been repaired using an 
FAA-approved repair.

    Note 1 to paragraph (h)(2):  Guidance for repairing the HPT 
rotor stage 1 disk can be found in GE Repair Document RD # 150-1811-
P1, dated March 17, 2020.

(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)(1) of this AD. Information may be 
emailed 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

    (1) For more information about this AD, contact Scott Stevenson, 
Aviation Safety Engineer, ECO Branch, FAA, 1200 District Avenue, 
Burlington, MA 01803; phone: (781) 238-7132; fax: (781) 238-7759; 
email: [email protected].
    (2) For service information identified in this AD, 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 referenced service 
information at the FAA, Airworthiness Products Section, 1200 
District Avenue, Burlington, MA 01803. For information on the 
availability of this material at the FAA, call (781) 238-7759.

    Issued on September 30, 2021.
Lance T. Gant,
Director, Compliance & Airworthiness Division, Aircraft Certification 
Service.
[FR Doc. 2021-21905 Filed 10-7-21; 8:45 am]
BILLING CODE 4910-13-C