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.

Proposed Rules Federal Register

1847 

Vol. 89, No. 8 

Thursday, January 11, 2024 

DEPARTMENT OF TRANSPORTATION 

Federal Aviation Administration 

14 CFR Part 39 

[Docket No. FAA–2024–0030; Project 

Identifier AD–2023–01066–E] 

RIN 2120–AA64 

Airworthiness Directives; CFM 

International, S.A. 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 

CFM International (CFM) Model LEAP– 

1A23, LEAP–1A24, LEAP–1A24E1, 

LEAP–1A26, LEAP–1A26CJ, LEAP– 

1A26E1, LEAP–1A29, LEAP–1A29CJ, 

LEAP–1A30, LEAP–1A32, LEAP–1A33, 

LEAP–1A33B2, and LEAP–1A35A 

engines. This proposed AD was 

prompted by detection of melt-related 

freckles in the billet, which may reduce 

the life of certain high-pressure turbine 

(HPT) rotor interstage seals. This 

proposed AD would require removing 

the affected HPT rotor interstage seals 

from service and replacing with a part 

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 February 26, 

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–2024–0030; 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 service information identified 

in this NPRM, contact CFM 

International, S.A., GE Aviation Fleet 

Support, 1 Neumann Way, M/D Room 

285, Cincinnati, OH 45215; phone: (877) 

432–3272; email: aviation.fleetsupport@

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 (817) 222–5110. 

FOR FURTHER INFORMATION CONTACT: 

Mehdi Lamnyi, Aviation Safety 

Engineer, FAA, 2200 South 216th Street, 

Des Moines, WA 98198; phone: (781) 

238–7743; email: mehdi.lamnyi@

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–2024–0030; Project Identifier AD– 

2023–01066–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 

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 Mehdi Lamnyi, 

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 

The FAA was notified by the 

manufacturer of the detection of meltrelated freckles in the billet, which may 

reduce the life of certain HPT rotor 

interstage seals. Through the 

manufacturer’s investigation, it was 

determined that these affected parts may 

have subsurface anomalies that 

developed during the manufacturing 

process, resulting in a lower life 

capability. This condition, if not 

addressed, could result in failure of the 

HPT rotor interstage seal, release of 

uncontained debris, 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 Under 1 

CFR Part 51 

The FAA reviewed CFM Service 

Bulletin LEAP–1A–72–00–0492–01A– 

930A–D, Issue 001–00, dated April 6, 

2023, which provides the serial 

numbers of the affected HPT rotor 

interstage seals and specifies procedures 

for replacement of the HPT rotor 


ddrumheller on DSK120RN23PROD with PROPOSALS1
1848 Federal Register / Vol. 89, No. 8 / Thursday, January 11, 2024 / Proposed Rules 

interstage seal. 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 require 

accomplishing the actions specified in 

the service information already 

described. 

Costs of Compliance 

The FAA estimates that this AD, if 

adopted as proposed, would affect 1 

engine installed on an airplane of U.S. 

registry. 

The FAA estimates the following 

costs to comply with this proposed AD: 

ESTIMATED COSTS

Action Labor cost Parts cost Cost per 

product 

Cost on U.S. 

operators 

Remove HPT rotor interstage seal ................. 225 work-hours × $85 per hour = $19,125 .... $168,000 $187,125 $187,125 

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 

■ 1. The authority citation for part 39 

continues to read as follows: 

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

§ 39.13 [Amended] 

■ 2. The FAA amends § 39.13 by adding 

the following new airworthiness 

directive: 

CFM International, S.A.: Docket No. FAA– 

2024–0030; Project Identifier AD–2023– 

01066–E. 

(a) Comments Due Date 

The FAA must receive comments on this 

airworthiness directive (AD) by February 26, 

2024. 

(b) Affected ADs 

None. 

(c) Applicability 

This AD applies to CFM International, S.A. 

(CFM) Model LEAP–1A23, LEAP–1A24, 

LEAP–1A24E1, LEAP–1A26, LEAP–1A26CJ, 

LEAP–1A26E1, LEAP–1A29, LEAP–1A29CJ, 

LEAP–1A30, LEAP–1A32, LEAP–1A33, 

LEAP–1A33B2, and LEAP–1A35A engines. 

(d) Subject 

Joint Aircraft System Component (JASC) 

Code 7250, Turbine Section. 

(e) Unsafe Condition 

This AD was prompted by detection of 

melt-related freckles in the billet, which may 

reduce the life of certain high-pressure 

turbine (HPT) rotor interstage seals. The FAA 

is issuing this AD to prevent failure of the 

HPT rotor interstage seal. The unsafe 

condition, if not addressed, could result in 

release of uncontained debris, 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 engines with an affected HPT rotor 

interstage seal installed, before exceeding the 

applicable threshold specified in Table 1 of 

paragraph 3.E., Compliance, of CFM Service 

Bulletin (SB) LEAP–1A–72–00–0492–01A– 

930A–D, Issue 001–00, dated April 6, 2023 

(CFM SB LEAP–1A–72–00–0492–01A–930A– 

D, Issue 001–00), or at the next HPT rotor 

module exposure, whichever occurs first 

after the effective date of this AD, remove the 

affected HPT rotor interstage seal from 

service and replace it with a part eligible for 

installation. 

(h) Definitions 

(1) For the purpose of this AD, an ‘‘affected 

HPT rotor interstage seal’’ is any HPT rotor 

interstage seal having part number 

2466M68P02 and a serial number listed in 

Table 1 of paragraph 3.E., Compliance, of 

CFM SB LEAP–1A–72–00–0492–01A–930A– 

D, Issue 001–00. 

(2) For the purpose of this AD, a ‘‘part 

eligible for installation’’ is any HPT rotor 

interstage seal having a serial number that is 

not listed in Table 1 of paragraph 3.E., 

Compliance, of CFM SB LEAP–1A–72–00– 

0492–01A–930A–D, Issue 001–00. 

(3) For the purpose of this AD, an ‘‘HPT 

rotor module exposure’’ is an engine shop 

visit during which the HPT rotor assembly is 

fully removed from the engine core. 

(i) 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 the AIR–520 Continued 

Operational Safety Branch, send it to the 

attention of the person identified in 

paragraph (j) of this AD and email to ANEAD-AMOC@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) Additional Information 

For more information about this AD, 

contact Mehdi Lamnyi, Aviation Safety 

Engineer, FAA, 2200 South 216th Street, Des 


ddrumheller on DSK120RN23PROD with PROPOSALS1
Federal Register / Vol. 89, No. 8 / Thursday, January 11, 2024 / Proposed Rules 1849 

Moines, WA 98198; phone: (781) 238–7743; 

email: mehdi.lamnyi@faa.gov. 

(k) 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) CFM International, S.A. (CFM) Service 

Bulletin LEAP–1A–72–00–0492–01A–930A– 

D, Issue 001–00, dated April 6, 2023. 

(ii) [Reserved] 

(3) For service information identified in 

this AD, contact CFM International, S.A., 

Aviation Operations Center, 1 Neumann 

Way, M/D Room 285, Cincinnati, OH 45125; 

phone: (877) 432–3272; email: fleetsupport@

ge.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 (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-locationsoremailfr.inspection@nara.gov. 

Issued on January 5, 2024. 

Victor Wicklund, 

Deputy Director, Compliance & Airworthiness 

Division, Aircraft Certification Service. 

[FR Doc. 2024–00377 Filed 1–10–24; 8:45 am] 

BILLING CODE 4910–13–P 

DEPARTMENT OF TRANSPORTATION 

Federal Aviation Administration 

14 CFR Part 39 

[Docket No. FAA–2024–0026; Project 

Identifier MCAI–2023–00776–T] 

RIN 2120–AA64 

Airworthiness Directives; MHI RJ 

Aviation ULC (Type Certificate 

Previously Held by Bombardier, Inc.) 

Airplanes 

AGENCY: Federal Aviation 

Administration (FAA), DOT. 

ACTION: Notice of proposed rulemaking 

(NPRM). 

SUMMARY: The FAA proposes to adopt a 

new airworthiness directive (AD) for all 

MHI RJ Aviation ULC Model CL–600– 

2E25 (Regional Jet Series 1000) 

airplanes. This proposed AD was 

prompted by a determination that new 

or more restrictive airworthiness 

limitations are necessary. This proposed 

AD would require revising the existing 

maintenance or inspection program, as 

applicable, to incorporate new or more 

restrictive airworthiness limitations, as 

specified in a Transport Canada AD, 

which is proposed for incorporation by 

reference (IBR). 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 February 26, 

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–2024–0026; 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 mandatory 

continuing airworthiness information 

(MCAI), any comments received, and 

other information. The street address for 

Docket Operations is listed above. 

Material Incorporated by Reference: 

• For Transport Canada material that 

is proposed for IBR in this NPRM, 

contact Transport Canada, Transport 

Canada National Aircraft Certification, 

159 Cleopatra Drive, Nepean, Ontario 

K1A 0N5, Canada; telephone 888–663– 

3639; email TC.AirworthinessDirectivesConsignesdenavigabilite.TC@tc.gc.ca; 

website tc.canada.ca/en/aviation. It is 

also available at regulations.gov under 

Docket No. FAA–2024–0026. 

• You may view this service 

information at the FAA, Airworthiness 

Products Section, Operational Safety 

Branch, 2200 South 216th St., Des 

Moines, WA. For information on the 

availability of this material at the FAA, 

call 206–231–3195. 

FOR FURTHER INFORMATION CONTACT: 

Fatin Saumik, Aviation Safety Engineer, 

FAA, 1600 Stewart Avenue, Suite 410, 

Westbury, NY 11590; telephone 516– 

228–7300; email 9-avs-nyaco-cos@

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–2024–0026; Project Identifier 

MCAI–2023–00776–T’’ 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 

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 Fatin Saumik, 

Aviation Safety Engineer, FAA, 1600 

Stewart Avenue, Suite 410, Westbury, 

NY 11590; telephone 516–228–7300; 

email 9-avs-nyaco-cos@faa.gov. Any 

commentary that the FAA receives 

which is not specifically designated as 

CBI will be placed in the public docket 

for this rulemaking. 

Background 

Transport Canada, which is the 

aviation authority for Canada, has 

issued AD CF–2023–43, dated June 21, 

2023 (Transport Canada AD CF–2023– 

43) (also referred to as the MCAI), to 

correct an unsafe condition for all MHI 

RJ Aviation ULC Model CL–600–2E25 

(Regional Jet Series 1000) airplanes. The 

MCAI states that new or more restrictive 

airworthiness limitations have been 

developed. 

The FAA is proposing this AD to 

prevent potential fatigue cracking and 


ddrumheller on DSK120RN23PROD with PROPOSALS1