DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2023-2002; Project Identifier MCAI-2023-00176-E;
Amendment 39-22668; AD 2024-02-04]
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: Final rule.

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SUMMARY: The FAA is superseding Airworthiness Directive (AD) 2021-13-07
for all GE Aviation Czech s.r.o. (GEAC) (type certificate previously
held by WALTER Engine a.s., Walter a.s., and MOTORLET a.s.) Model
M601D-11, M601E-11, M601E-11A, M601E-11AS, M601E-11S, and M601F
engines. AD 2021-13-07 required recalculating the life of critical
parts and, depending on the results of the recalculation, replacing
those critical parts. AD 2021-13-07 also required replacing a certain
compressor case. Since the FAA issued AD 2021-13-07, the manufacturer
published the airworthiness limitations section (ALS) of the existing
engine maintenance manual (EMM), which includes the calculations for
the life of critical parts addressed by AD 2021-13-07 and prompted this
AD. This AD continues to require the replacement of a certain
centrifugal compressor case. This AD also includes an additional part
number as an option for the replacement, and limits the applicability
of this AD, as specified in a European Union Aviation Safety Agency
(EASA) AD, which is incorporated by reference. The FAA is issuing this
AD to address the unsafe condition on these products.

DATES: This AD is effective March 28, 2024.
The Director of the Federal Register approved the incorporation by
reference of a certain publication listed in this AD as of March 28,
2024.

ADDRESSES:
AD Docket: You may examine the AD docket at regulations.gov under
Docket No. FAA-2023-2002; 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, the mandatory continuing airworthiness
information (MCAI), 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 service information identified in this final rule,
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.
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 under Docket No. FAA-2023-2002.

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:

Background

The FAA issued a notice of proposed rulemaking (NPRM) to amend 14
CFR part 39 to supersede AD 2021-13-07, Amendment 39-21612 (86 FR
31601, June 15, 2021), (AD 2021-13-07). AD 2021-13-07 applied to all
GEAC Model M601D-11, M601E-11, M601E-11A, M601E-11AS, M601E-11S, and
M601F engines. AD 2021-13-07 required recalculating the life of
critical parts and, depending on the results of the recalculation,
replacing critical parts. AD 2021-13-07 also requires replacing a
certain compressor case. The FAA issued AD 2021-13-07 to prevent the
failure of the engine.
The NPRM published in the Federal Register on October 27, 2023 (88
FR 73778). The NPRM was prompted by EASA AD 2021-0125R1, dated January
30, 2023 (EASA AD 2021-0125R1) (also referred to as the MCAI), issued
by EASA, which is the Technical Agent for the Member States of the
European Union. The MCAI states that the manufacturer published the
ALS, which incorporates certain requirements addressed by EASA
Emergency AD 2021-0125-E, and that EASA published EASA AD 2023-0020,
dated January 23, 2023 (EASA AD 2023-0020), which requires
accomplishment of the actions specified in the ALS. The MCAI limits the
applicability to M601E engines with a centrifugal compressor case
having part number M601-154.61 installed and removes the requirements
that have been incorporated in the ALS.
You may examine the MCAI in the AD docket at regulations.gov under
Docket No. FAA-2023-2002.
In the NPRM, the FAA proposed to continue to require the
replacement of a certain centrifugal compressor case. In the NPRM, the
FAA also proposed to require accomplishing the actions specified in the
MCAI.

Discussion of Final Airworthiness Directive

Comments

The FAA received no comments on the NPRM or on the determination of
the costs.

Conclusion

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 reviewed the relevant data 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, this AD is
adopted as proposed in the NPRM.

Related Service Information Under 1 CFR Part 51

The FAA reviewed EASA AD 2021-0125R1, which specifies procedures
for replacing the centrifugal compressor case, limits the applicability
to certain M601E engines, and removes the requirements that have been
incorporated in the ALS.
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.

Differences Between This AD and the MCAI

The MCAI applies to GEAC Model M601E engines, and this AD does not
because they do not have an FAA type certificate.

Costs of Compliance

The FAA estimates that this AD affects 13 engines installed on
airplanes of U.S. registry.
The FAA estimates the following costs to comply with this 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 has determined that 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.

Sec. 39.13 [Amended]

2. The FAA amends Sec. 39.13 by:

a. Removing Airworthiness Directive 2021-13-07, Amendment 39-21612 (86
FR 31601, June 15, 2021); and

b. Adding the following new airworthiness directive: