63834 Federal Register / Vol. 88, No. 179 / Monday, September 18, 2023 / Rules and Regulations 

NRC stated that if no significant adverse 

comments were received, the direct 

final rule would become effective on 

October 17, 2023. The NRC did not 

receive any comments on the direct 

final rule. Therefore, this direct final 

rule will become effective as scheduled. 

Dated: September 13, 2023. 

For the Nuclear Regulatory Commission. 

Cindy K. Bladey, 

Chief, Regulatory Analysis and Rulemaking 

Support Branch, Division of Rulemaking, 

Environmental, and Financial Support Office 

of Nuclear Material Safety and Safeguards. 

[FR Doc. 2023–20142 Filed 9–15–23; 8:45 am] 

BILLING CODE 7590–01–P 

DEPARTMENT OF TRANSPORTATION 

Federal Aviation Administration 

14 CFR Part 39 

[Docket No. FAA–2023–0663; Project 

Identifier AD–2023–00020–E; Amendment 

39–22534; AD 2023–17–08] 

RIN 2120–AA64 

Airworthiness Directives; General 

Electric Company Engines 

AGENCY: Federal Aviation 

Administration (FAA), DOT. 

ACTION: Final rule. 

SUMMARY: The FAA is adopting a new 

airworthiness directive (AD) for certain 

General Electric Company (GE) Model 

GEnx–1B and GEnx–2B engines. This 

AD was prompted by a manufacturer 

investigation that revealed that certain 

stages 6–10 compressor rotor spools and 

forward seals were manufactured from 

powder metal material suspected to 

contain iron inclusion. This AD requires 

the replacement of the affected stages 6– 

10 compressor rotor spools and forward 

seals. The FAA is issuing this AD to 

address the unsafe condition on these 

products. 

DATES: This AD is effective October 23, 

2023. 

The Director of the Federal Register 

approved the incorporation by reference 

of certain publications listed in this AD 

as of October 23, 2023. 

ADDRESSES: 

AD Docket: You may examine the AD 

docket at regulations.gov by searching 

for and locating Docket No. FAA–2023– 

0663; 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. 

Material Incorporated by Reference: 

• For GE service information 

identified in this final rule, contact 

General Electric Company, 1 Neumann 

Way, Cincinnati, OH 45215; phone: 

(513) 552–3272; email: 

aviation.fleetsupport@ge.com; website: 

geaviation.com/support. 

• 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. It is also 

available at regulations.gov by searching 

for and locating Docket No. FAA–2023– 

0663. 

FOR FURTHER INFORMATION CONTACT: 

Alexei Marqueen, Aviation Safety 

Engineer, FAA, 2200 South 216th Street, 

Des Moines, WA 98198; phone: (781) 

238–7178; email: alexei.t.marqueen@

faa.gov. 

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 Model GEnx–1B64/ 

P2, GEnx–1B67/P2, GEnx–1B70/75/P2, 

GEnx–1B70/P2, GEnx–1B70C/P2, 

GEnx–1B74/75/P2, GEnx–1B76/P2, 

GEnx–1B76A/P2, and GEnx–2B67/P 

engines. The NPRM published in the 

Federal Register on April 13, 2023 (88 

FR 22383). The NPRM was prompted by 

a report from the manufacturer of the 

detection of iron inclusion in a highpressure turbine stage 2 disk 

manufactured from the same powder 

metal material used to manufacture 

certain stages 6–10 compressor rotor 

spools and forward seals. A 

manufacturer investigation determined 

that the iron inclusion was introduced 

during the manufacturing process from 

raw material filtering screens that had 

degraded, and certain stages 6–10 

compressor rotor spools and forward 

seals manufactured using the same 

process may have reduced material 

properties and a lower fatigue life 

capability due to the iron inclusion. 

Further investigation by the 

manufacturer identified additional 

degraded filtering screens which had 

the potential to increase the population 

of parts that were subjected to iron 

inclusion during manufacturing. As a 

result of its investigation, GE published 

service information that specifies 

procedures for the removal and 

replacement of certain stages 6–10 

compressor rotor spools and forward 

seals. In the NPRM, the FAA proposed 

to require removal of the affected stages 

6–10 compressor rotor spools and 

forward seals and replacement with a 

part 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 comments from 

three commenters. The commenters 

were the Airline Pilots Association, 

International (ALPA), American 

Airlines (AA), and United Airlines. AA 

requested changes to the NPRM. ALPA 

supported the NPRM without change. 

United Airlines reviewed the NPRM but 

did not include any additional 

comments. The following presents the 

comments received on the NPRM and 

the FAA’s response to each comment. 

Request for Guidance on Thrust Limit 

AA requested that the FAA provide 

guidance on which thrust limit to apply 

for engines with multiple thrust ratings. 

AA also asked if the FAA’s intention is 

to set the thrust limit based on the 

thrust rating at removal, or if the 

expectation is to apply the lowest limit 

that the engine operated under. AA 

noted that it has a spool operating 

where the proposed AD limit would be 

6,200 cycles, but it previously operated 

at a higher thrust rating such that the 

limit was 1,000 cycles less. 

The FAA agrees to clarify. The 

intention of the thrust limit is for 

operators to remove the affected stages 

6–10 compressor rotor spool or affected 

forward seal from service at the next 

piece-part exposure, or no later than the 

cyclic thresholds listed in the applicable 

service bulletins that are incorporated 

by reference. The FAA notes that since 

multiple thrust ratings are listed in the 

service bulletins, the intent is to set the 

cyclic removal threshold based on the 

thrust rating that is applicable at the 

time the AD is issued, not at the lowest 

thrust rating that a part has ever 

operated under. The FAA did not 

change this AD as a result of this 

comment. 

Request To Update Service Bulletin 

Shorthand 

AA requested that the FAA add the 

revision levels to the shorthand 

reference of each service bulletin in 

paragraph (g) and (h) of this AD. AA 

noted that –1B operators do not have 

access to –2B bulletins, and vice versa, 

so –1B operators will not be notified if 

the –2B service bulletin is revised, and 


lotter on DSK11XQN23PROD with RULES1
Federal Register / Vol. 88, No. 179 / Monday, September 18, 2023 / Rules and Regulations 63835 

will not be able to confirm that the 

information between the two service 

bulletins continues to match. 

The FAA agrees and has revised the 

shorthand reference for each applicable 

service bulletin to include the revision 

level in paragraphs (c), (g) and (h) of this 

AD. 

Conclusion 

The FAA reviewed the relevant data, 

considered any comments received, and 

determined that air safety requires 

adopting this AD as proposed. 

Accordingly, the FAA is issuing this AD 

to address the unsafe condition on these 

products. Except for minor editorial 

changes, and any other changes 

described previously, this AD is 

adopted as proposed in the NPRM. 

None of the changes will increase the 

economic burden on any operator. 

Related Service Information Under 1 

CFR Part 51 

The FAA reviewed GE GEnx–1B 

Service Bulletin 72–0515, R00, dated 

January 31, 2023. The FAA also 

reviewed GE GEnx–2B Service Bulletin 

72–0452, R00, dated January 31, 2023. 

This service information specifies 

procedures for removal and replacement 

of the stages 6–10 compressor rotor 

spool and forward seal. These 

documents are distinct since they apply 

to different engine models. 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 the ADDRESSES section. 

Interim Action 

The FAA considers this AD to be an 

interim action. If final action is later 

identified, the FAA might consider 

additional rulemaking. 

Costs of Compliance 

The FAA estimates that this AD 

affects 13 engines installed on airplanes 

of U.S. registry. The FAA estimates that 

9 of the 13 engines will require 

replacing the stages 6–10 compressor 

rotor spool and 4 of the 13 engines will 

require replacing the forward seal. 

The FAA estimates the following 

costs to comply with this AD: 

Estimated Costs 

Action Labor cost Parts cost Cost per 

product 

Cost on U.S. 

operators 

Replace stages 6–10 compressor rotor spool.8 work-hours × $85 per hour = $680 ..................................... $841,088 $841,768 $7,575,912 

Replace forward seal .............. 8 work-hours × $85 per hour = $680 ..................................... 389,976 390,656 1,562,624 

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 

■ 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: 

2023–17–08 General Electric Company: 

Amendment 39–22534; Docket No. 

FAA–2023–0663; Project Identifier AD– 

2023–00020–E. 

(a) Effective Date 

This airworthiness directive (AD) is 

effective October 23, 2023. 

(b) Affected ADs 

None. 

(c) Applicability 

This AD applies to General Electric 

Company (GE) Model GEnx–1B64/P2, GEnx– 

1B67/P2, GEnx–1B70/75/P2, GEnx–1B70/P2, 

GEnx–1B70C/P2, GEnx–1B74/75/P2, GEnx– 

1B76/P2, GEnx–1B76A/P2, and GEnx–2B67/ 

P engines with an installed: 

(1) Stages 6–10 compressor rotor spool 

having a part number (P/N) and serial 

number (S/N) listed in paragraph 4, 

Appendix—A, Table 1 of GE GEnx–1B 

Service Bulletin 72–0515, R00, dated January 

31, 2023 (GEnx–1B 72–0515 R00); or 

(2) Forward seal having a P/N and S/N 

listed in paragraph 4, Appendix—A, Table 2 

of GEnx–1B 72–0515 R00; or 

(3) Stages 6–10 compressor rotor spool 

having a P/N and S/N listed in paragraph 4, 

Appendix—A, Table 1 of GE GEnx–2B 

Service Bulletin 72–0452, R00, dated January 

31, 2023. (GEnx–2B 72–0452 R00); or 

(4) Forward seal having a P/N and S/N 

listed in paragraph 4, Appendix—A, Table 2 

of GEnx–2B 72–0452 R00. 

(d) Subject 

Joint Aircraft System Component (JASC) 

Code 7230, Turbine Engine Compressor 

Section; 7250, Turbine Section. 

(e) Unsafe Condition 

This AD was prompted by a manufacturer 

investigation that revealed certain stages 6– 

10 compressor rotor spools and forward seals 

were subject to iron inclusion introduced 

during the manufacturing process. The FAA 

is issuing this AD to prevent fracture and 

potential uncontained failure of certain 

stages 6–10 compressor rotor spools and 

forward seals. The unsafe condition, if not 

addressed, could result in uncontained 

debris release, damage to the engine, and 

damage to the aircraft. 


lotter on DSK11XQN23PROD with RULES1
63836 Federal Register / Vol. 88, No. 179 / Monday, September 18, 2023 / Rules and Regulations 

(f) Compliance 

Comply with this AD within the 

compliance times specified, unless already 

done. 

(g) Required Actions 

(1) For affected Model GEnx–1B engines, at 

the next piece-part exposure after the 

effective date of this AD, or before the 

affected stages 6–10 compressor rotor spool 

reaches the cyclic removal threshold listed in 

paragraph 4., Appendix—A, Table 1 of 

GEnx–1B 72–0515 R00, whichever occurs 

first, remove the affected stages 6–10 

compressor rotor spool from service and 

replace with a part eligible for installation. 

(2) For affected Model GEnx–1B engines, at 

the next piece-part exposure after the 

effective date of this AD, or before the 

affected forward seal exceeds the cyclic 

removal threshold listed in paragraph 4., 

Appendix—A, Table 2 of GEnx–1B 72–0515 

R00, whichever occurs first, remove the 

affected forward seal from service and 

replace with a part eligible for installation. 

(3) For affected Model GEnx–2B engines, at 

the next piece-part exposure after the 

effective date of this AD, or before the 

affected stages 6–10 compressor rotor spool 

exceeds the cyclic removal threshold listed 

in paragraph 4., Appendix—A, Table 1 of 

GEnx–2B 72–0452 R00, whichever occurs 

first, remove the affected stages 6–10 

compressor rotor spool from service and 

replace with a part eligible for installation. 

(4) For affected Model GEnx–2B engines, at 

the next piece-part exposure after the 

effective date of this AD, or before the 

affected forward seal exceeds the cyclic 

removal threshold listed in paragraph 4., 

Appendix—A, Table 2 of GEnx–2B 72–0452 

R00, whichever occurs first, remove the 

affected forward seal from service and 

replace with a part eligible for installation. 

(h) Definitions 

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

eligible for installation’’ is any stages 6–10 

compressor rotor spool or forward seal with 

a P/N and S/N not listed in paragraph 4, 

Appendix—A, Table 1 or paragraph 4, 

Appendix—A, Table 2 of GEnx–1B 72–0515 

R00 or GEnx–2B 72–0452 R00. 

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

exposure’’ is when the affected part is 

removed from the engine. 

(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 certification office, 

send it to the attention of the person 

identified in paragraph (j) of this AD and 

email to: ANE-AD-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) Related Information 

For more information about this AD, 

contact Alexei Marqueen, Aviation Safety 

Engineer, FAA, 2200 South 216th Street, Des 

Moines, WA 98198; phone: (781) 238–7178; 

email: alexei.t.marqueen@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) General Electric Company (GE) GEnx– 

1B Service Bulletin 72–0515, R00, dated 

January 31, 2023. 

(ii) GE GEnx–2B Service Bulletin 72–0452, 

R00, dated January 31, 2023. 

(3) For GE service information identified in 

this AD, contact General Electric Company, 

1 Neumann Way, Cincinnati, OH 45215; 

phone: (513) 552–3272; email: 

aviation.fleetsupport@ge.com; website: 

geaviation.com/support. 

(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 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: fr.inspection@nara.gov, or go to: 

www.archives.gov/federal-register/cfr/ibrlocations.html. 

Issued on August 24, 2023. 

Victor Wicklund, 

Deputy Director, Compliance & Airworthiness 

Division, Aircraft Certification Service. 

[FR Doc. 2023–20063 Filed 9–15–23; 8:45 am] 

BILLING CODE 4910–13–P 

DEPARTMENT OF TRANSPORTATION 

Federal Aviation Administration 

14 CFR Part 71 

[Docket No. FAA–2023–0583; Airspace 

Docket No. 22–ACE–20] 

RIN 2120–AA66 

Modification of Class E Airspace; 

Alliance Municipal Airport, Alliance, NE 

AGENCY: Federal Aviation 

Administration (FAA), DOT. 

ACTION: Final rule; delay of effective 

date; modification of order. 

SUMMARY: This action delays the original 

effective date and changes the version of 

FAA Order JO 7400.11 amended in the 

final rule published on August 16, 2023. 

This action also republishes the text of 

that final rule modifying Class E 

airspace extending upward from 700 

feet above the surface to adequately 

contain all instrument flight rule (IFR) 

procedures at Alliance Municipal 

Airport, NE. This action supports the 

safety and management of IFR 

operations at the airport. 

DATES: The final rule published at 88 FR 

55553, August 16, 2023, is delayed until 

0901 UTC, November 30, 2023. This 

action is effective date 0901 UTC, 

November 30, 2023. The Director of the 

Federal Register approves this 

incorporation by reference action under 

1 CFR part 51, subject to the annual 

revision of FAA Order JO 7400.11 and 

publication of conforming amendments. 

ADDRESSES: A copy of the Notice of 

Proposed Rulemaking (NPRM), all 

comments received, this final rule, and 

all background material may be viewed 

online at www.regulations.gov using the 

FAA Docket number. Electronic 

retrieval help and guidelines are 

available on the website. It is available 

24 hours each day, 365 days each year. 

FAA Order JO 7400.11H Airspace 

Designations and Reporting Points, and 

subsequent amendments can be viewed 

online at www.faa.gov/air_traffic/ 

publications/. You may also contact the 

Rules and Regulations Group, Office of 

Policy, Federal Aviation 

Administration, 800 Independence 

Avenue SW, Washington DC 20591; 

telephone: (202) 267–8783. 

FOR FURTHER INFORMATION CONTACT: 

Keith T. Adams, Federal Aviation 

Administration, Western Service Center, 

Operations Support Group, 2200 S 

216th Street, Des Moines, WA 98198, 

telephone: (206) 231–2428. 

SUPPLEMENTARY INFORMATION: 

Authority for This Rulemaking 

The FAA’s authority to issue rules 

regarding aviation safety is found in 

Title 49 of the United States Code. 

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. This rulemaking is 

promulgated under the authority 

described in Subtitle VII, Part A, 

Subpart I, Section 40103. Under that 

section, the FAA is charged with 

prescribing regulations to assign the use 

of the airspace necessary to ensure the 

safety of aircraft and the efficient use of 

airspace. This regulation is within the 

scope of that authority as it modifies 

Class E airspace to supports the safety 

and management of IFR operations at 

Alliance Municipal Airport. 


lotter on DSK11XQN23PROD with RULES1