Federal Register / Vol. 87, No. 72 / Thursday, April 14, 2022 / Proposed Rules 22149 

transmission, FPI all surfaces of the main 

transmission support case lateral mounts for 

a crack. If there is any crack, before further 

flight, remove the main transmission support 

case assembly from service. 

(h) Alternative Methods of Compliance 

(AMOCs) 

(1) The Manager, DSCO 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 Related Information. 

Information may be emailed to: 9-ASW-190- 

COS@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. 

(i) Related Information 

(1) For more information about this AD, 

contact Hye Yoon Jang, Aerospace Engineer, 

Delegation Oversight Section, DSCO Branch, 

Compliance & Airworthiness Division, FAA, 

10101 Hillwood Pkwy., Fort Worth, TX 

76177; telephone (817) 222–5190; email 

hye.yoon.jang@faa.gov. 

(2) For ASTM service information 

identified in this AD, you may purchase the 

ASTM standard from ASTM International at 

https://www.astm.org/. You may view this 

material at the FAA, Office of the Regional 

Counsel, Southwest Region, 10101 Hillwood 

Pkwy., Room 6N–321, Fort Worth, TX 76177. 

For information on the availability of this 

material at the FAA, call (817) 222–5110. 

Issued on April 7, 2022. 

Ross Landes, 

Deputy Director for Regulatory Operations, 

Compliance & Airworthiness Division, 

Aircraft Certification Service. 

[FR Doc. 2022–07887 Filed 4–13–22; 8:45 am] 

BILLING CODE 4910–13–P 

DEPARTMENT OF TRANSPORTATION 

Federal Aviation Administration 

14 CFR Part 39 

[Docket No. FAA–2022–0459; Project 

Identifier MCAI–2021–00266–E] 

RIN 2120–AA64 

Airworthiness Directives; GE Aviation 

Czech s.r.o. (Type Certificate 

Previously Held by WALTER Engines 

a.s., Walter a.s., and MOTORLET a.s.) 

Turboprop 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 all 

GE Aviation Czech s.r.o. (GEAC) 

M601D–11 model turboprop engines. 

This proposed AD was prompted by the 

manufacturer revising the airworthiness 

limitation section (ALS) of the existing 

engine maintenance manual (EMM) to 

include a visual inspection of the 

centrifugal compressor case for cracks. 

This proposed AD would require 

revising the ALS of the existing EMM to 

incorporate a visual inspection of the 

centrifugal compressor case. 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 May 31, 2022. 

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 GE Aviation Czech, 

Beranovy ́ch 65, 199 02 Praha 9— 

Letnˇ any, Czech Republic; phone: +420 

222 538 999; email: tp.ops@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. 

Examining the AD Docket 

You may examine the AD docket at 

https://www.regulations.gov by 

searching for and locating Docket No. 

FAA–2022–0459; 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. 

FOR FURTHER INFORMATION CONTACT: 

Barbara Caufield, Aviation Safety 

Engineer, ECO Branch, FAA, 1200 

District Avenue, Burlington, MA 01803; 

phone: (781) 238–7146; email: 

barbara.caufield@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–2022–0459; Project Identifier 

MCAI–2021–00266–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 NPRM 

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 Barbara Caufield, 

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 European Union Aviation Safety 

Agency (EASA), which is the Technical 

Agent for the Member States of the 

European Union, has issued EASA AD 

2021–0060, dated March 3, 2021 

(referred to after this as ‘‘the MCAI’’), to 

address the unsafe condition on these 

products. The MCAI states: 

The airworthiness limitations for certain 

M601 engine models, which are approved by 


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22150 Federal Register / Vol. 87, No. 72 / Thursday, April 14, 2022 / Proposed Rules 

EASA, are currently defined and published 

in the ALS. These instructions have been 

identified as mandatory for continued 

airworthiness. 

Failure to accomplish these instructions 

could result in an unsafe condition. 

Recently, GEAC published the ALS, as 

defined in this [EASA] AD, introducing a 

visual inspection of the Centrifugal 

Compressor Case. 

For the reason described above, this 

[EASA] AD requires accomplishment of the 

actions specified in the ALS. 

You may obtain further information 

by examining the MCAI in the AD 

docket at https://www.regulations.gov 

by searching for and locating Docket No. 

FAA–2022–0459. 

FAA’s Determination 

This product has been approved by 

EASA and is approved for operation in 

the United States. Pursuant to the FAA’s 

bilateral agreement with the European 

Union, EASA has notified the FAA of 

the unsafe condition described in the 

MCAI and service information. The 

FAA is proposing this AD because the 

agency evaluated all the relevant 

information provided by EASA and has 

determined the unsafe condition 

described previously is likely to exist or 

develop in other products of the same 

type design. 

Related Service Information 

The FAA reviewed GE Aviation Czech 

Airworthiness Limitations R18, Section 

5. Mandatory Inspections, of the GE 

Aviation Czech EMM, Part No. 0982309, 

Revision No. 18, dated December 18, 

2020 (Airworthiness Limitations R18, 

Section 5. Mandatory Inspections). 

Airworthiness Limitations R18, Section 

5. Mandatory Inspections, of the EMM 

specifies procedures for performing a 

visual inspection of the centrifugal 

compressor case for cracks. 

Proposed AD Requirements in This 

NPRM 

This proposed AD would require 

revising the ALS of the existing EMM to 

incorporate a visual inspection of the 

centrifugal compressor case for cracks. 

An owner/operator (pilot) holding at 

least at least a private pilot certificate 

may revise the ALS of the existing 

EMM, and the owner/operator must 

enter compliance with the applicable 

paragraphs of the AD into the aircraft 

records in accordance with 14 CFR 

43.9(a)(1) through (4) and 14 CFR 

91.417(a)(2)(v). This is an exception to 

the FAA’s standard maintenance 

regulations. 

Differences Between This Proposed AD 

and the MCAI or Service Information 

The MCAI specifies replacing each 

component before exceeding the 

applicable life limit and accomplishing 

all the applicable maintenance tasks 

within the thresholds and intervals, as 

defined in the ALS. This proposed AD 

would require revising the ALS of the 

existing EMM to incorporate a visual 

inspection of the centrifugal compressor 

case. The MCAI specifies that if 

discrepancies are found during the 

accomplishment of the EASA AD, to 

accomplish corrective actions in 

accordance with existing GEAC 

instructions. The MCAI also specifies to 

contact GEAC for approved instructions 

if a detected discrepancy cannot be 

corrected using existing GEAC 

instruction. This proposed AD would 

not require performing corrective 

actions in accordance with existing 

GEAC instructions or contacting GEAC 

for approved instructions. The MCAI 

specifies revising the aircraft 

maintenance program within 12 months 

from its effective date. This proposed 

AD would require revising the ALS of 

the existing EMM to incorporate a visual 

inspection of the centrifugal compressor 

case within 90 days after the effective 

date of this proposed AD. 

The MCAI and GE Aviation Czech 

Airworthiness Limitations R18, Section 

5. Mandatory Inspections, apply to 

GEAC M601D–1, M601D–2, M601D–11, 

M601D–11NZ, and M601Z model 

turboprop engines. This proposed AD 

would not apply to GEAC M601D–1, 

M601D–2, M601D–11NZ, and M601Z 

model turboprop engines because these 

model turboprop engines do not have an 

FAA type certificate. 

Costs of Compliance 

The FAA estimates that this AD, if 

adopted as proposed, would affect 7 

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 Parts cost Cost per 

product 

Cost on U.S. 

operators 

Revise the ALS of the EMM ........................... 1 work-hour × $85 per hour = $85 ................. $0 $85 $595 

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: 


lotter on DSK11XQN23PROD with PROPOSALS1
Federal Register / Vol. 87, No. 72 / Thursday, April 14, 2022 / Proposed Rules 22151 

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: 

GE Aviation Czech s.r.o (Type Certificate 

previously held by WALTER Engines 

a.s., Walter a.s., and MOTORLET a.s.): 

Docket No. FAA–2022–0459; Project 

Identifier MCAI–2021–00266–E. 

(a) Comments Due Date 

The FAA must receive comments on this 

airworthiness directive (AD) by May 31, 

2022. 

(b) Affected ADs 

None. 

(c) Applicability 

This AD applies to GE Aviation Czech 

s.r.o. M601D–11 model turboprop engines. 

(d) Subject 

Joint Aircraft System Component (JASC) 

Code 7230, Turbine Engine Compressor 

Section. 

(e) Unsafe Condition 

This AD was prompted by the 

manufacturer revising the airworthiness 

limitation section (ALS) of the existing 

engine maintenance manual (EMM) to 

include a visual inspection of the centrifugal 

compressor case for cracks. The FAA is 

issuing this AD to prevent failure of the 

centrifugal compressor case. The unsafe 

condition, if not addressed, could result in 

failure of the centrifugal compressor case, 

engine separation, and loss of the airplane. 

(f) Compliance 

Comply with this AD within the 

compliance times specified, unless already 

done. 

(g) Required Actions 

(1) Within 90 days after the effective date 

of this AD, revise the ALS of the existing 

EMM by incorporating Figure 1 to paragraph 

(g)(1) of this AD. 

BILLING CODE 4910–13–P 


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22152 Federal Register / Vol. 87, No. 72 / Thursday, April 14, 2022 / Proposed Rules 

(2) After revising the ALS of the existing 

EMM required by paragraph (g)(1) of this AD, 

no alternative inspection intervals may be 

used unless they are approved as provided in 

paragraph (h) of this AD. 

(3) The action required by paragraph (g)(1) 

of this AD may be performed by the owner/ 

operator (pilot) holding at least a private pilot 

certificate and must be entered into the 

aircraft records showing compliance with 

this AD in accordance with 14 CFR 43.9(a)(1) 

through (4) and 14 CFR 91.417(a)(2)(v). The 

record must be maintained as required by 14 

CFR 91.417, 121.380, or 135.439. 

(h) 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 ECO Branch, send it to 

the attention of the person identified in 

paragraph (i)(1) of this AD and email: 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. 

(i) Related Information 

(1) For more information about this AD, 

contact Barbara Caufield, Aviation Safety 

Engineer, ECO Branch, FAA, 1200 District 

Avenue, Burlington, MA 01803; phone: (781) 

238–7146; email: barbara.caufield@faa.gov. 

(2) Refer to European Union Aviation 

Safety Agency (EASA) AD 2021–0060, dated 

March 3, 2021, for more information. You 

may examine the EASA AD in the AD docket 

at https://www.regulations.gov by searching 

for and locating it in Docket No. FAA–2022– 

0459. 


lotter on DSK11XQN23PROD with PROPOSALS1EP14AP22.045</GPH>

Figure 1 to Paragraph (g)(l)- Visual Inspection of the Centrifugal Compressor 

Case 

S. Mandatory lnapgctlons 

5.1 Visual inspectlqn of Centrifugal Compressor Case 

Accomplishment lnstrudion 

Do a visual Inspection of the compressor case In the specified areas, shmm in Figure 1, for 

every 100±10 Flight Hours. Use magnifying lens 10X for inspecilion. No visible cracks are 

allowed. 

Equipment: 

The fo!bwtng equipment I& reqund and may be obtained a& shown: 

- A 150-watt standard spotlight or 40-Watt high lnlan&lly spo111ght or alternative 

(Commerdat) to acquire necessary illumination at minimum 10QOlux. 

- Magnification equipment 10X (Commercial). 

Figure 1. CenttUgal Compreuor case 

Inspection area 

boundaries around 

circumferential wekJ 
Federal Register / Vol. 87, No. 72 / Thursday, April 14, 2022 / Proposed Rules 22153 

Issued on April 8, 2022. 

Lance T. Gant, 

Director, Compliance & Airworthiness 

Division, Aircraft Certification Service. 

[FR Doc. 2022–08005 Filed 4–13–22; 8:45 am] 

BILLING CODE 4910–13–C 

DEPARTMENT OF TRANSPORTATION 

Federal Aviation Administration 

14 CFR Part 39 

[Docket No. FAA–2021–0511; Project 

Identifier AD–2020–01229–E] 

RIN 2120–AA64 

Airworthiness Directives; Williams 

International Co., L.L.C. Turbofan 

Engines 

AGENCY: Federal Aviation 

Administration (FAA), DOT. 

ACTION: Supplemental notice of 

proposed rulemaking (SNPRM). 

SUMMARY: The FAA is revising a notice 

of proposed rulemaking (NPRM) that 

applied to certain Williams 

International Co., L.L.C. (Williams) 

FJ44–2A, FJ44–2C, FJ44–3A, and FJ44– 

3A–24 model turbofan engines. This 

action revises the NPRM by expanding 

the applicability, updating the estimated 

costs information, updating the 

compliance time, and adding an 

installation prohibition. This action also 

revises the NPRM by updating the 

service information references. The FAA 

is proposing this airworthiness directive 

(AD) to address the unsafe condition on 

these products. Since these actions 

would impose an additional burden 

over those in the NPRM, the agency is 

requesting comments on this SNPRM. 

DATES: The FAA must receive comments 

on this SNPRM by May 31, 2022. 

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 SNPRM, contact Williams 

International, Product Support, 2000 

Centerpoint Parkway, Pontiac, MI 

48341; phone: (800) 859–3544; website: 

http://www.williams-int.com/productsupport. You may view this service 

information at the FAA, Chicago ACO, 

2300 East Devon Avenue, Des Plaines, 

IL 60018. For information on the 

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–2021–0511; 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 

SNPRM, any comments received, and 

other information. The street address for 

Docket Operations is listed above. 

FOR FURTHER INFORMATION CONTACT: Kyle 

Bush, Aviation Safety Engineer, Chicago 

ACO, FAA, 2300 East Devon Avenue, 

Des Plaines, IL 60018; phone: (847) 294– 

7870; email: kyle.bush@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–2021–0511; Project Identifier AD– 

2020–01229–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 again revise 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 proposed 

AD. 

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 SNPRM 

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 SNPRM, 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 SNPRM. Submissions containing 

CBI should be sent to Kyle Bush, 

Aviation Safety Engineer, Chicago ACO, 

FAA, 2300 East Devon Avenue, Des 

Plaines, IL 60018. 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 issued an NPRM to amend 

14 CFR part 39 by adding an AD that 

would apply to Williams FJ44–2A, 

FJ44–2C, FJ44–3A, and FJ44–3A–24 

model turbofan engines. The NPRM 

published in the Federal Register on 

June 25, 2021 (86 FR 33579). The NPRM 

was prompted by a report of cracks in 

the high-pressure turbine (HPT) disk 

posts and failure of an HPT disk post, 

resulting in the contained fracture of an 

HPT disk post and blade. Williams 

initiated an investigation to understand 

the root cause of the cracks and to 

determine the necessary corrective 

action. Metallurgical evaluation showed 

cracking related to intergranular 

oxidation related to HPT disk post metal 

temperatures. 

As a result of this investigation, 

Williams determined the root cause of 

this cracking was due to higher HPT 

disk post temperatures and a difference 

in manufacturing processes. Williams 

determined that these cracks have only 

occurred on HPT disks with part 

number (P/N) 67093 installed on FJ44– 

2A or FJ44–2C model turbofan engines. 

Williams subsequently published 

service information specifying 

procedures to remove the HPT disk, P/ 

N 67093. In the NPRM, the FAA 

proposed to require removing the HPT 

disk, P/N 67093, from service before 

reaching its new life limit and replacing 

it with a part eligible for installation. 

Actions Since the NPRM Was Issued 

Since the FAA issued the NPRM, 

Williams notified the FAA that revised 

service information was available. The 

revised service information, Williams 

International Service Bulletin (SB) 

WISB–72–1032, Revision 2, dated June 

4, 2020, adds additional serialnumbered FJ44–2A, FJ44–2C, and FJ44– 

3A model turbofan engines to the 

effectivity and updates the compliance 

time for replacing the HPT disk. The 

FAA determined that the additional 


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