DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2023-1811; Project Identifier MCAI-2023-00146-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.) Engines

AGENCY: Federal Aviation Administration (FAA), DOT.

ACTION: Notice of proposed rulemaking (NPRM).

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SUMMARY: The FAA proposes to supersede Airworthiness Directive (AD)
2023-01-07, which applies to all GE Aviation Czech s.r.o. (GEAC) (type
certificate previously held by WALTER Engines a.s., Walter a.s., and
MOTORLET a.s.) Model H75-100, H75-200, H80, H80-100, H80-200, H85-100,
and H85-200 engines. AD 2023-01-07 requires revising the airworthiness
limitations section (ALS) of the existing engine maintenance manual
(EMM) and the operator's existing approved maintenance or inspection
program, as applicable, to incorporate updated coefficients and
recalculate the cycles accumulated on critical parts. Since the FAA
issued AD 2023-01-07, the manufacturer revised the ALS of the EMM to
introduce new and more restrictive airworthiness limitations and
associated thresholds and intervals for life-limited parts, which
prompted this proposed AD. This proposed AD would require revising the
ALS of the existing EMM and the operator's existing approved engine
maintenance or inspection program, as applicable, to incorporate new
and more restrictive instructions and associated thresholds and
intervals for life-limited parts, as specified in a European Union
Aviation Safety Agency (EASA) 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 NPRM by October 23, 2023.

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-2023-1811; 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 service information that is proposed for IBR in this
NPRM, contact EASA, Konrad-Adenauer-Ufer 3, 50668 Cologne, Germany;
phone: +49 221 8999 000; email: ADs@easa.europa.eu; website:
easa.europa.eu. You may find this material on the EASA website at
ad.easa.europa.eu. It is also available at regulations.gov under Docket
No. FAA-2023-1811.
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: Barbara Caufield, Aviation Safety
Engineer, FAA, 1600 Stewart Avenue, Suite 410, Westbury, NY 11590;
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-2023-1811; Project Identifier
MCAI-2023-00146-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
the 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
Barbara Caufield, Aviation Safety Engineer, FAA, 1600 Stewart Avenue,
Suite 410, Westbury, NY 11590. 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 AD 2023-01-07, Amendment 39-22301 (88 FR 7355,
February 3, 2023; corrected February 16, 2023 (88 FR 10013)) (AD 2023-
01-07), for all GEAC Model H75-100, H75-200, H80, H80-100, H80-200,
H85-100, and H85-200 engines. AD 2023-01-07 was prompted by an MCAI
originated by EASA, which is the Technical Agent for the Member States of the
European Union. EASA issued EASA AD 2022-0008, dated January 19, 2022
(EASA AD 2022-0008), to address an unsafe condition identified as
failure of the engine. EASA AD 2022-0008 stated that the airworthiness
limitations for H series engine models have been identified as
mandatory for continued airworthiness, and that failure to accomplish
these instructions could result in an unsafe condition. EASA AD 2022-
0008 also explained that the manufacturer published a revised ALS to
introduce updated coefficients for the calculation of the cyclic life
and safe life for the main shaft.
AD 2023-01-07 requires revising the ALS of the existing EMM and the
operator's existing approved maintenance or inspection program, as
applicable, to incorporate updated coefficients and recalculate the
cycles accumulated on critical parts. The FAA issued AD 2023-01-07 to
prevent failure of the engine.

Actions Since AD 2023-01-07 Was Issued

Since the FAA issued AD 2023-01-07, EASA superseded EASA AD 2022-
0008 and issued EASA AD 2023-0021, dated January 23, 2023 (EASA AD
2023-0021) (also referred to after this as the MCAI). The MCAI states
that the manufacturer revised the ALS to introduce new and more
restrictive instructions and associated thresholds and intervals for
life-limited parts. The MCAI also states that GEAC published an Alert
Service Bulletin, ASB-H75-72-10-00-0062, ASB-H80-72-10-00-0107, ASB-
H85-72-10-00-0051, ASB-M601F-72-10-00-0070, ASB-M601E-72-10-00-0120,
ASB-M601D-72-10-00-0087 and ASB-M601Z-72-10-00-0069; Revision 1, dated
January 20, 2023, published as a single document, which provides
instructions to determine the accumulated life of certain propeller
shafts.
You may examine the MCAI in the AD docket at regulations.gov under
Docket No. FAA-2023-1811.

Related Service Information Under 1 CFR Part 51

The FAA reviewed EASA AD 2023-0021, which specifies procedures for
operators to revise the ALS of the existing EMM and the operator's
existing approved engine maintenance or inspection program, as
applicable, to incorporate new and more restrictive instructions and
associated thresholds and intervals for life-limited parts, as
applicable to each engine model.
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.

FAA's Determination

These products have been approved by the aviation authority of
another country and are approved for operation in the United States.
Pursuant to the FAA's bilateral agreement with this State of Design
Authority, it has notified the FAA of the unsafe condition described in
the MCAI referenced above. 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.

Proposed AD Requirements in This NPRM

This proposed AD would require accomplishing the actions specified
in the MCAI described previously, except for any differences identified
as exceptions in the regulatory text of this proposed AD and as
discussed under ``Differences Between this Proposed AD and the MCAI.''
The owner/operator (pilot) holding at least a private pilot certificate
may revise the ALS of the existing EMM and must enter compliance with
the applicable paragraph of this proposed AD into the engine
maintenance records in accordance with 14 CFR 43.9(a) and
91.417(a)(2)(v). The pilot may perform this action because it only
involves revising the pilot's manual. This action could be performed
equally well by a pilot or a mechanic. This is an exception to the
FAA's standard maintenance regulations.

Explanation of Required Compliance Information

In the FAA's ongoing efforts to improve the efficiency of the AD
process, the FAA developed a process to use some civil aviation
authority (CAA) ADs as the primary source of information for compliance
with requirements for corresponding FAA ADs. The FAA has since
coordinated with other manufacturers and CAAs to use this process. As a
result, the FAA proposes to incorporate by reference EASA AD 2023-0021
in the FAA final rule. This proposed AD would, therefore, require
compliance with EASA AD 2023-0021 in its entirety through that
incorporation, except for any differences identified as exceptions in
the regulatory text of this proposed AD. Using common terms that are
the same as the heading of a particular section in the EASA AD does not
mean that operators need comply only with that section. For example,
where the AD requirement refers to ``all required actions within the
compliance times,'' compliance with this AD requirement is not limited
to the section titled ``Required Action(s) and Compliance Time(s)'' in
EASA AD 2023-0021. Service information required by the EASA AD for
compliance will be available at regulations.gov by searching for and
locating Docket No. FAA-2023-1811 after the FAA final rule is
published.

Differences Between This Proposed AD and the MCAI

Where EASA AD 2023-0021 defines the AMP as the approved Aircraft
Maintenance Programme containing the tasks on the basis of which the
scheduled maintenance is conducted to ensure the continuing
airworthiness of each operated engine, this proposed AD defines the AMP
as the aircraft maintenance program containing the tasks on the basis
of which the scheduled maintenance is conducted to ensure the
continuing airworthiness of each operated airplane.
Where EASA AD 2023-0021 defines the ALS as the Airworthiness
Limitations Section of the GEAC EMM No. 0983402 Revision 25, dated
November 21, 2022, this proposed AD defines the ALS as the
airworthiness limitations section of the GEAC EMM No. 0983402 Revision
26, dated February 1, 2023. The ALS in Revision 26 of the EMM is
unchanged from Revision 25 of the EMM.
Where paragraph (3) of EASA AD 2023-0021 specifies revising the
approved Aircraft Maintenance Programme within 12 months after the
effective date of EASA AD 2023-0021, this proposed AD would require
revising the ALS of the existing approved engine maintenance or
inspection program, as applicable, within 90 days after the effective
date of this AD.
This proposed AD would not require compliance with paragraphs (1),
(2), (4), and (5) of EASA AD 2023-0021.

Costs of Compliance

The FAA estimates that this AD, if adopted as proposed, would
affect 33 engines installed on airplanes of U.S. registry.
The FAA estimates the following costs to comply with this proposed
AD:

Estimated Costs

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 that the 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.

Sec. 39.13 [Amended]

2. The FAA amends Sec. 39.13 by:

a. Removing Airworthiness Directive 2023-01-07, Amendment 39-22301 (88
FR 7355, February 3, 2023; corrected February 16, 2023 (88 FR 10013));
and

b. Adding the following new airworthiness directive: