Federal Register / Vol. 90, No. 5 / Wednesday, January 8, 2025 / Rules and Regulations 1361 

22907; Docket No. FAA–2024–2024; 

Project Identifier MCAI–2024–00140–T. 

(a) Effective Date 

This airworthiness directive (AD) is 

effective February 12, 2025. 

(b) Affected ADs 

None. 

(c) Applicability 

This AD applies to all Airbus Defense and 

Space S.A. (formerly known as 

Construcciones Aeronauticas, S.A.) Model 

CN–235, CN–235–200, and CN–235–300 

airplanes, certificated in any category. 

(d) Subject 

Air Transport Association (ATA) of 

America Code 32, Landing Gear. 

(e) Unsafe Condition 

This AD was prompted by a torn bulkhead 

seal found jamming the nose landing gear 

emergency cable pulley. Due to the similarity 

of design, the main landing gear emergency 

cable pulley could be exposed to the same 

failure mode. The FAA is issuing this AD to 

address this potential unsafe condition, 

which could prevent the emergency 

extension of the landing gears when required, 

causing damage to the airplane and possible 

injury to occupants. 

(f) Compliance 

Comply with this AD within the 

compliance times specified, unless already 

done. 

(g) Requirements 

Except as specified in paragraphs (h) and 

(i) of this AD: Comply with all required 

actions and compliance times specified in, 

and in accordance with, European Union 

Aviation Safety Agency (EASA) AD 2024– 

0054, dated February 26, 2024 (EASA AD 

2024–0054). 

(h) Exceptions to EASA AD 2024–0054 

(1) Where EASA AD 2024–0054 refers to its 

effective date, this AD requires using the 

effective date of this AD. 

(2) Where paragraph 3.1.1 of the Alert 

Operators Transmission (AOT) specified in 

EASA AD 2024–0054, states ‘‘each year (1 

Year between 8 and 10 Years since 

component installation) since the 

inspection,’’ this AD requires replacing that 

text with ‘‘within one year after the last 

inspection’’. 

(3) This AD does not adopt the ‘‘Remarks’’ 

section of EASA AD 2024–0054. 

(i) No Reporting Requirement 

Although the material referenced in EASA 

AD 2024–0054 specifies to submit certain 

information to the manufacturer, this AD 

does not include that requirement. 

(j) Additional AD Provisions 

The following provisions also apply to this 

AD: 

(1) Alternative Methods of Compliance 

(AMOCs): The Manager, International 

Validation 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 

responsible Flight Standards Office, as 

appropriate. If sending information directly 

to the manager of the International Validation 

Branch, mail it to the address identified in 

paragraph (k) of this AD. Information may be 

emailed to: AMOC@faa.gov. Before using any 

approved AMOC, notify your appropriate 

principal inspector, or lacking a principal 

inspector, the manager of the responsible 

Flight Standards Office. 

(2) Contacting the Manufacturer: For any 

requirement in this AD to obtain instructions 

from a manufacturer, the instructions must 

be accomplished using a method approved 

by the Manager, International Validation 

Branch, FAA; or EASA; or Airbus Defense 

and Space S.A.’s EASA Design Organization 

Approval (DOA). If approved by the DOA, 

the approval must include the DOAauthorized signature. 

(k) Additional Information 

For more information about this AD, 

contact Shahram Daneshmandi, Aviation 

Safety Engineer, FAA, 1600 Stewart Avenue, 

Suite 410, Westbury, NY 11590; phone: 206– 

231–3220; email: shahram.daneshmandi@

faa.gov. 

(l) Material Incorporated by Reference 

(1) The Director of the Federal Register 

approved the incorporation by reference of 

the material listed in this paragraph under 5 

U.S.C. 552(a) and 1 CFR part 51. 

(2) You must use this material as 

applicable to do the actions required by this 

AD, unless this AD specifies otherwise. 

(i) European Union Aviation Safety Agency 

(EASA) AD 2024–0054, dated February 26, 

2024. 

(ii) [Reserved] 

(3) For EASA material identified in this 

AD, contact EASA, Konrad-Adenauer-Ufer 3, 

50668 Cologne, Germany; telephone +49 221 

8999 000; email ADs@easa.europa.eu; 

website easa.europa.eu. You may find this 

EASA AD on the EASA website at 

ad.easa.europa.eu. 

(4) You may view this material 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. 

(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-locations or email fr.inspection@nara.gov. 

Issued on December 4, 2024. 

Victor Wicklund, 

Deputy Director, Compliance & Airworthiness 

Division, Aircraft Certification Service. 

[FR Doc. 2025–00146 Filed 1–7–25; 8:45 am] 

BILLING CODE 4910–13–P 

DEPARTMENT OF TRANSPORTATION 

Federal Aviation Administration 

14 CFR Part 39 

[Docket No. FAA–2024–0755; Project 

Identifier AD–2023–00521–E; Amendment 

39–22909; AD 2024–25–07] 

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–1B64, GEnx–1B64/P1, GEnx– 

1B64/P2, GEnx–1B67, GEnx–1B67/P1, 

GEnx–1B67/P2, GEnx–1B70, GEnx– 

1B70/75/P1, GEnx–1B70/75/P2, GEnx– 

1B70/P1, GEnx–1B70/P2, GEnx–1B70C/ 

P1, GEnx–1B70C/P2, GEnx–1B74/75/P1, 

GEnx–1B74/75/P2, GEnx–1B76/P2, 

GEnx–1B76A/P2, GEnx–2B67, GEnx– 

2B67B, and GEnx–2B67/P engines. This 

AD was prompted by a manufacturer 

evaluation that determined a lower life 

limit may be necessary for certain stages 

6–10 compressor rotor spools than 

allowed by the engine shop manual 

(ESM). This AD requires a one-time 

inspection of the stages 6–10 spools for 

previously accomplished blend repairs, 

a one-time inspection of the blend 

repairs on the stages 6–10 spools for 

compliance with the updated allowable 

limits, and replacement if necessary. 

The FAA is issuing this AD to address 

the unsafe condition on these products. 

DATES: This AD is effective February 12, 

2025. 

The Director of the Federal Register 

approved the incorporation by reference 

of certain publications listed in this AD 

as of February 12, 2025. 

ADDRESSES: 

AD Docket: You may examine the AD 

docket at regulations.gov under Docket 

No. FAA–2024–0755; 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 material identified in this 

AD, contact GE, 1 Neumann Way, 

Cincinnati, OH 45215; phone: (513) 


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552–3272; email: aviation.fleetsupport@

ge.com; website: ge.com. 

• You may view this material 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 under Docket No. FAA– 

2024–0755. 

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/ 

P1, GEnx–1B64/P2, GEnx–1B67, GEnx– 

1B67/P1, GEnx–1B67/P2, GEnx–1B70, 

GEnx–1B70/75/P1, GEnx–1B70/75/P2, 

GEnx–1B70/P1, GEnx–1B70/P2, GEnx– 

1B70C/P1, GEnx–1B70C/P2, GEnx– 

1B74/75/P1, GEnx–1B74/75/P2, GEnx– 

1B76/P2, GEnx–1B76A/P2, GEnx–2B67, 

GEnx–2B67B, and GEnx–2B67/P 

engines with certain stages 6–10 spool 

installed. The NPRM published in the 

Federal Register on March 25, 2024 (89 

FR 20553). The NPRM was prompted by 

a manufacturer evaluation which 

determined that a lower life limit may 

be necessary for certain stages 6–10 

spools than that allowed in the engine 

shop manual. In the NPRM, the FAA 

proposed to require accomplishing a 

one-time inspection of the stages 6–10 

spools for previously accomplished 

blend repairs, a one-time inspection of 

the blend repairs on the stages 6–10 

spools for compliance with the updated 

allowable limits, and replacement, if 

necessary, within compliance times 

specified in GE GEnx–1B Service 

Bulletin 72–0525, R00, dated October 4, 

2023 (GEnx–1B SB 72–0525, R00), or 

GEnx–2B Service Bulletin 72–0460, 

R00, dated October 4, 2023 (GEnx–2B 

SB 72–0460, R00). Depending on the 

part numbers and serial numbers of the 

affected stages 6–10 spools, the NPRM 

proposed to require these actions to be 

accomplished at the next piece-part 

exposure after the effective date of the 

proposed AD, or before the affected 

stages 6–10 spool reaches the cyclic 

removal threshold of up to 11,894 cycles 

since new. 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 

eight commenters. The commenters 

were American Airlines, Air Line Pilots 

Association, International (ALPA), 

Boeing Commercial Airplanes (Boeing), 

GE, Japan Airlines, Qatar Airways, 

United Airlines, and United Parcel 

Service (UPS). ALPA and Boeing 

supported the NPRM without change. 

The following presents the comments 

received on the NPRM and the FAA’s 

response to each comment. 

Request for Clarification of Compliance 

Time 

Qatar Airways requested clarification 

of the compliance threshold specified in 

the NPRM. The commenter pointed out 

that the compliance thresholds in the 

service information specify that ‘‘at the 

next piece-part exposure of the affected 

6–10 spools, but before the affected 6– 

10 spools reach the cycle since new 

threshold for inspection listed in 

paragraph 4., Appendix—A, Table 1,’’ 

whereas the NPRM expressed the 

compliance time as ‘‘At the next piecepart exposure after the effective date of 

this AD or before the affected stages 6– 

10 spool reaches the cyclic removal 

threshold specified in paragraph 4., 

Appendix-A, Table 1 of GEnx–1B 72– 

0525, R00 or GEnx–2B SB 72–0460, R00, 

as applicable.’’ The commentor stated 

that the compliance time as written, is 

unclear about when to take action and 

which takes priority (next piece part or 

cycle thresholds). 

The FAA agrees that the compliance 

time is unclear. Paragraph (g) of this AD 

has been updated to state that the 

required action is to be performed at 

next piece part exposure or before the 

spool reaches the cycle removal 

thresholds, whichever occurs first. 

Request To Update the Definition of 

‘‘Part Eligible for Installation’’ 

American Airlines and UPS requested 

that the FAA reword paragraph (h)(2) of 

the proposed AD to allow installation of 

an affected part, provided that the part 

passes the required inspections. UPS 

pointed out that in both paragraph (g) of 

the proposed AD and the service 

information, replacement of an affected 

part is only required if a previously 

accomplished blend repair is found and 

is also not within the allowable limits. 

However, the proposed definition 

would prohibit installation of any 

affected part, regardless of the 

inspection results. In addition, UPS 

requested that paragraph (h)(2) of the 

proposed AD be reworded to redefine a 

‘‘part eligible for installation’’ as a stages 

6–10 spool that does not have a P/N and 

S/N defined in paragraph 4, Appendix 

A, Table 1 of GEnx–1B 72–0525, R00 or 

GEnx–2B 72–0460, R00, or a stages 6– 

10 spool with a P/N and S/N that is 

listed in paragraph 4, Appendix A, 

Table 1 of GEnx–1B 72–0525, R00 or 

GEnx–2B 72–0460 that has been 

inspected and found to be within the 

allowable limits. 

The FAA agrees that a stages 6–10 

spool that passes inspection does not 

need to be removed from service. 

Therefore, paragraph (h)(2) of this AD 

has been updated to reflect this change. 

Request To Revise the Summary 

GE requested that the FAA revise the 

SUMMARY of the NPRM to clarify that for 

certain stages 6–10 compressor rotor 

spools there is a potential life shortfall 

to that specified in the ESM, instead of 

an absolute or definite life shortfall. GE 

stated that the evaluation of the repair 

limits demonstrated that at the worst 

size and location a stages 6–10 spool 

would have an ultimate life lower than 

that published in the ESM. However, 

there is no evidence to show that any of 

the affected stages 6–10 spools have a 

repair at the worst size and location. GE 

pointed out that for this reason, an 

inspection is required to determine if 

there is a possibility of the ultimate life 

lower than that published in the ESM. 

GE recommended adding the terms 

‘‘may be’’ to the SUMMARY to clarify that 

not all stages 6–10 spools will have a 

lower life limit. 

The FAA agrees that clarification is 

necessary and has updated the SUMMARY

of this AD accordingly. 

Request To Update the Required 

Service Information 

GE requested that the FAA update the 

NPRM to specify the latest revision of 

the service information. GE specified 

the intention to revise GE GEnx–1B SB 

72–0525, R00 and GEnx–2B SB 72– 

0460, R00, and added that the updated 

revisions will not change actions or 

accomplishment instructions but will 

add wording indicating hardware that 

meets current ESM limits will not have 

a lower limit than published in CH05. 

The FAA agrees and has revised this 

AD to refer to GE GEnx–1B Service 

Bulletin 72–0525, R01, dated June 10, 

2024 (GEnx–1B SB 72–0525, R01), and 

GEnx–2B Service Bulletin 72–0460, 

R01, dated June 10, 2024 (GEnx–2B SB 

72–0460, R01), as the appropriate source 

of service information. Additionally, the 

FAA has updated this AD to include 

credit for the actions required by 

paragraph (g) of this AD, if those actions 

were done prior to the effective date of 


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this AD using GE GEnx–1B SB 72–0525, 

R00 and GEnx–2B SB 72–0460, R00. 

Request To Clarify the Applicability of 

ESM Life Limits 

United Airlines requested that the 

FAA include additional verbiage in the 

service information and the proposed 

AD that, in the case of an affected part 

passing the inspection, that part retains 

the ultimate life limit specified in the 

ESM. United Airlines stated that 

paragraph (g) of the proposed AD was 

not specific about what actions to take 

if the affected part passed the 

inspection. However, the service 

information specifies that no further 

action is necessary. Also, paragraph 

1.E.(3) of GEnx–1B SB 72–0525, R00 

and GEnx–2B SB 72–0460, R00 states 

that ‘‘affected 6–10 spools were found to 

have life limit lower than ultimate life 

limit.’’ 

The FAA disagrees with the request. 

The life limits listed in the ESM are 

mandatory and applicable regardless of 

the actions required by this AD. Should 

any affected part be found to have a 

blend repair that is not in compliance 

with the allowable limits specified in 

the applicable service information, then 

this AD requires removal from service 

and replacement of that specific part. 

However, this AD does not change the 

life limits of parts that pass the 

inspection. Therefore, the FAA has not 

changed this AD in this regard. 

Request To Specify the Affected Engine 

Models in the Required Actions 

Japan Airlines requested that the FAA 

revise paragraph (g) of the proposed AD 

to specify the affected engine models at 

the beginning of each of the sentences, 

to provide better clarity. Japan Airlines 

referred to paragraph (g) of AD 2023– 

17–08 as an example. 

The FAA disagrees with the request. 

AD 2023–17–08 specifies multiple 

affected parts on both the GEnx–1B and 

GEnx–2B Model engines, and therefore 

the FAA used multiple paragraphs for 

each affected part and each engine 

model. In this AD, the only affected 

parts are stages 6–10 spools, making it 

unnecessary to specify engine models in 

paragraph (g) of this AD. 

Changes After the NPRM Was 

Published 

After the NPRM was published, the 

FAA determined that Model GEnx–1B64 

engines were inadvertently left out of 

the applicability. None of these engines 

with the affected stages 6–10 spools are 

installed on airplanes on the U.S. 

registry. This model has been added to 

the applicability of the final rule in case 

one of these engines with affected 6–10 

spools are installed on an airplane 

registered for operation in United States. 

Adding this model to the applicability 

does not increase the burden to U.S. 

operators over the already proposed 

requirements, so issuing a supplemental 

notice of proposed rulemaking is 

unnecessary. 

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. 

Material Incorporated by Reference 

Under 1 CFR Part 51 

The FAA reviewed GE GEnx–1B SB 

72–0525, R01, and GEnx–2B SB 72– 

0460, R01. This service information 

identifies the part numbers and serial 

numbers of affected stages 6–10 spools; 

and specifies instructions for a one-time 

inspection of the stages 6–10 spools for 

previously accomplished blend repairs, 

a one-time inspection of the blend 

repairs on the stages 6–10 spools for 

compliance with the updated allowable 

limits, and replacement if necessary. 

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 ADDRESSES section. 

Costs of Compliance 

The FAA estimates that this AD 

affects 6 engines installed on airplanes 

of U.S. registry. 

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 

Inspect stages 6–10 spools ............................ 8 work-hours × $85 per hour = $680 ............. $0 $680 $4,080 

Inspect previous blend repairs ........................ 1 work-hours × $85 per hour = $85 ............... 0 85 510 

The FAA estimates the following 

costs to do any necessary replacements 

that would be required based on the 

results of the inspections. The agency 

has no way of determining the number 

of engines that might need this 

replacement: 

ON-CONDITION COSTS

Action Labor cost Parts cost Cost per 

product 

Replace stages 6–10 spool .......................................... 8 work-hours × $85 per hour = $680 ........................... $1,307,600 $1,308,280 

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 


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1364 Federal Register / Vol. 90, No. 5 / Wednesday, January 8, 2025 / Rules and Regulations 

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: 

2024–25–07 General Electric Company: 

Amendment 39–22909; Docket No. 

FAA–2024–0755; Project Identifier AD– 

2023–00521–E. 

(a) Effective Date 

This airworthiness directive (AD) is 

effective February 12, 2025. 

(b) Affected ADs 

None. 

(c) Applicability 

This AD applies to General Electric 

Company (GE) Model GEnx–1B64, GEnx– 

1B64/P1, GEnx–1B64/P2, GEnx–1B67, GEnx– 

1B67/P1, GEnx–1B67/P2, GEnx–1B70, GEnx– 

1B70/75/P1, GEnx–1B70/75/P2, GEnx–1B70/ 

P1, GEnx–1B70/P2, GEnx–1B70C/P1, GEnx– 

1B70C/P2, GEnx–1B74/75/P1, GEnx–1B74/ 

75/P2, GEnx–1B76/P2, GEnx–1B76A/P2, 

GEnx–2B67, GEnx–2B67B, and GEnx–2B67/P 

engines with an installed: 

(1) Stages 6–10 compressor rotor spool 

(stages 6–10 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 72–0525, R01, 

dated June 10, 2024 (GEnx–1B SB 72–0525, 

R01); or 

(2) Stages 6–10 spool having a P/N and S/ 

N listed in paragraph 4, Appendix—A, Table 

1 of GE GEnx–2B Service Bulletin 72–0460, 

R01, dated June 10, 2024 (GEnx–2B SB 72– 

0460, R01). 

(d) Subject 

Joint Aircraft System Component (JASC) 

Code 7230, Turbine Engine Compressor 

Section. 

(e) Unsafe Condition 

This AD was prompted by a manufacturer 

evaluation which determined that a lower 

life limit may be necessary for certain stages 

6–10 spools than that allowed in the engine 

shop manual. The FAA is issuing this AD to 

prevent fracture and potential uncontained 

failure of the stages 6–10 spools. The unsafe 

condition, if not addressed, could result in 

uncontained debris release, damage to the 

engine, and damage to the aircraft. 

(f) Compliance 

Comply with this AD within the 

compliance times specified, unless already 

done. 

(g) Required Actions 

At the next piece-part exposure after the 

effective date of this AD or before the affected 

stages 6–10 spool reaches the cyclic removal 

threshold specified in paragraph 4., 

Appendix—A, Table 1 of GEnx–1B 72–0525, 

R01 or GEnx–2B SB 72–0460, R01, as 

applicable, whichever occurs first, do the 

following actions: 

(1) Inspect the stages 6–10 spool for 

previously accomplished blend repairs in 

accordance with the Accomplishment 

Instructions, paragraph 3.B.(1) of GEnx–1B 

SB 72–0525, R01 or GEnx–2B SB 72–0460, 

R01, as applicable. 

(2) If during any inspection required by 

paragraph (g)(1) of this AD, any stages 6–10 

spool is found to have a previously 

accomplished blend repair, before further 

flight, inspect the blend repair for 

compliance with the allowable limits in 

accordance with the Accomplishment 

Instructions, paragraph 3.B.(2) of GEnx–1B 

SB 72–0525, R01 or GEnx–2B SB 72–0460, 

R01, as applicable. 

(3) If during any inspection required by 

paragraph (g)(2) of this AD, any stages 6–10 

spool is found to have a previously 

accomplished blend repair that is not within 

the allowable limits, before further flight, 

remove the stages 6–10 spool from service 

and replace with a part eligible for 

installation in accordance with the 

Accomplishment Instructions, paragraph 

3.B.(2)(a)1 or 3.B.(2)(b)1 of GEnx–1B SB 72– 

0525, R01 or GEnx–2B SB 72–0460, R01, as 

applicable. 

(h) Definition 

For the purposes of this AD: 

(1) A ‘‘piece-part exposure’’ is when the 

stages 6–10 spool is disassembled from the 

high-pressure compressor rotor assembly. 

(2) A ‘‘part eligible for installation’’ is 

either a stages 6–10 spool that does not have 

a P/N and S/N identified in paragraph 4, 

Appendix—A, Table 1 of GEnx–1B 72–0525, 

R01 or GEnx–2B 72–0460, R01, or a stages 6– 

10 spool that does have a P/N and S/N 

identified in paragraph 4, Appendix—A, 

Table 1 of GEnx–1B 72–0525, R01 or GEnx– 

2B 72–0460, R01, provided that the affected 

part is not removed in accordance with 

paragraph (g)(3) of this AD. 

(i) Credit for Previous Actions 

You may take credit for the actions 

required by paragraph (g) of this AD if you 

performed those actions before the effective 

date of this AD using GE GEnx–1B Service 

Bulletin 72–0525, R00, dated October 4, 

2023, or GEnx–2B Service Bulletin 72–0460, 

R00, dated October 4, 2023. 

(j) 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 (k) 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. 

(k) 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. 

(l) Material Incorporated by Reference 

(1) The Director of the Federal Register 

approved the incorporation by reference 

(IBR) of the material listed in this paragraph 

under 5 U.S.C. 552(a) and 1 CFR part 51. 

(2) You must use this material as 

applicable to do the actions required by this 

AD, unless the AD specifies otherwise. 

(i) GE GEnx–1B Service Bulletin 72–0525, 

R01, dated June 10, 2024. 

(ii) GE GEnx–2B Service Bulletin 72–0460, 

R01, dated June 10, 2024. 

(3) For GE material identified in this AD, 

contact GE 1 Neumann Way, Cincinnati, OH 

45215; phone: (513) 552–3272; email: 

aviation.fleetsupport@ge.com; website: 

ge.com. 

(4) You may view this material 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. 


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Federal Register / Vol. 90, No. 5 / Wednesday, January 8, 2025 / Rules and Regulations 1365 

(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 December 6, 2024. 

Peter A. White, 

Deputy Director, Integrated Certificate 

Management Division, Aircraft Certification 

Service. 

[FR Doc. 2025–00208 Filed 1–7–25; 8:45 am] 

BILLING CODE 4910–13–P 

DEPARTMENT OF TRANSPORTATION 

Federal Aviation Administration 

14 CFR Part 39 

[Docket No. FAA–2024–1898; Project 

Identifier AD–2023–01013–E; Amendment 

39–22904; AD 2024–25–02] 

RIN 2120–AA64 

Airworthiness Directives; CFM 

International, S.A. Engines 

AGENCY: Federal Aviation 

Administration (FAA), DOT. 

ACTION: Final rule. 

SUMMARY: The FAA is adopting a new 

airworthiness directive (AD) for certain 

CFM International, S.A. (CFM) Model 

LEAP–1B engines. This AD was 

prompted by a report of a quality escape 

involving certain high-pressure 

compressor (HPC) stage 2 seals 

manufactured without detailed finish 

machining, which could result in 

deeper rubs and mechanical damage to 

the seal teeth of the stage 3–4 

compressor rotor blisk (stage 3–4 blisk) 

of the mating compressor rotor during 

initial operation. This AD requires a 

visual inspection of the HPC stage 2 

seal, a visual inspection of the forward 

arm seal teeth of the stage 3–4 blisk, an 

eddy current inspection (ECI) of the 

forward arm seal teeth of the stage 3–4 

blisk, and replacement of the HPC stage 

2 seal and the stage 3–4 blisk, if 

necessary. The FAA is issuing this AD 

to address the unsafe condition on these 

products. 

DATES: This AD is effective February 12, 

2025. 

The Director of the Federal Register 

approved the incorporation by reference 

of a certain publication listed in this AD 

as of February 12, 2025. 

ADDRESSES: 

AD Docket: You may examine the AD 

docket at regulations.gov under Docket 

No. FAA–2024–1898; 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 CFM material identified in this 

AD, contact CFM, 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 material 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 under Docket No. FAA– 

2024–1898. 

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: 

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 CFM Model LEAP–1B 

engines. The NPRM published in the 

Federal Register on July 29, 2024 (89 FR 

60838). The NPRM was prompted by a 

report of a quality escape involving 

certain HPC stage 2 seals manufactured 

without detailed finish machining, 

which could result in deeper rubs and 

mechanical damage to the seal teeth of 

the stage 3–4 blisk of the mating 

compressor rotor during initial 

operation. In the NPRM, the FAA 

proposed to require a visual inspection 

of the HPC stage 2 seal, a visual 

inspection of the forward arm seal teeth 

of the stage 3–4 blisk, an ECI of the 

forward arm seal teeth of the stage 3–4 

blisk, and replacement of the HPC stage 

2 seal and the stage 3–4 blisk, if 

necessary. 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 six 

commenters. The commenters were The 

Boeing Company (Boeing), CFM, 

Ryanair, StandardAero, Southwest 

Airlines (SWA), and United Airlines 

(UAL). Boeing concurred with the 

contents of the NPRM and 

StandardAero expressed support for the 

NPRM. The following presents the 

comments received on the NPRM and 

the FAA’s response to each comment. 

Request To Remove Certain Engine 

Serial Numbers (ESNs) From the 

Applicability 

CFM and Ryanair requested that the 

FAA remove certain ESNs from the 

applicability of the proposed AD or 

include replacement of the HPC stage 2 

seal and the stage 3–4 blisk with new 

parts as an option for complying with 

the proposed AD. Both commenters 

stated that certain ESNs had already 

replaced the HPC stage 2 seal and the 

stage 3–4 blisk with new parts. Both 

commenters also pointed out that by 

replacing the HPC stage 2 seal and the 

stage 3–4 blisk with new parts, the 

unsafe condition is mitigated for those 

engines, but not as specified in the 

required actions of the proposed AD. 

Since this is a quality escape issue 

and limited to the parts originally 

installed on the engine, the FAA agrees 

for the reasons provided and has 

removed ESNs 60A676 and 60A669 

from the applicability of this AD. 

Request for Clarification of Difference 

With the Service Information 

StandardAero and UAL requested that 

the FAA provide clarification regarding 

why the borescope inspection (BSI) 

specified in the required service 

information is not required by the 

NPRM. StandardAero pointed out that 

the NPRM does not address why the BSI 

is not required. StandardAero also 

mentioned that the European Union 

Aviation Safety Agency (EASA) has a 

corresponding proposed AD (EASA 

PAD 24–108), which discussed and 

inferred that the BSIs have already been 

completed on all affected engines. 

StandardAero specifically requested 

that the FAA confirm that the BSIs have 

been completed on all the ESNs that are 

specified in the service information, and 

that the ESNs specified in the NPRM are 

those that require additional action due 

to the BSI results. UAL pointed out that 

the service information contains 

Required for Compliance (RC) steps for 

a BSI. UAL requested clarification of 

whether those steps are required by the 

NPRM and whether the BSI is 

acceptable for verifying the condition of 

the HPC stage 2 seal and the stage 3–4 

blisk. 

The FAA acknowledges the difference 

between the actions required by this AD 

and those specified in the service 

information. The engine manufacturer 

has provided the FAA with evidence 


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