DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2024-0461; Project Identifier AD-2023-00994-E;
Amendment 39-22767; AD 2024-12-03]
RIN 2120-AA64

Airworthiness Directives; CFE Company Engines

AGENCY: Federal Aviation Administration (FAA), DOT.

ACTION: Final rule.

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SUMMARY: The FAA is adopting a new airworthiness directive (AD) for
certain CFE Company (CFE) Model CFE738-1-1B engines. This AD was
prompted by a manufacturer investigation that revealed certain high-
pressure turbine (HPT) stage 1 and stage 2 disks were manufactured from
powder metal material suspected to contain iron inclusion. This AD
requires replacement of affected HPT stage 1 and stage 2 disks with
parts eligible for installation. The FAA is issuing this AD to address
the unsafe condition on these products.

DATES: This AD is effective August 13, 2024.
The Director of the Federal Register approved the incorporation by
reference of a certain publication listed in this AD as of August 13,
2024.

ADDRESSES:
AD Docket: You may examine the AD docket at regulations.gov under
Docket No. FAA-2024-0461; 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 CFE material, contact CFE Company, 111 S 34th Street,
Phoenix, AZ 85034; phone: (800) 601-3099; email:
CFE738DataCenter@honeywell.com; website: aerospace.honeywell.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-2024-0461.

FOR FURTHER INFORMATION CONTACT: Alexei Marqueen, Aviation Safety
Engineer, FAA, 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 that apply to certain CFE Model
CFE738-1-1B engines with HPT stage 1 and HPT stage 2 disks installed.
The NPRM published in the Federal Register on March 8, 2024 (89 FR
16710). The NPRM was prompted by a manufacturer investigation that
revealed certain HPT stage 1 and HPT stage 2 disks, installed on
certain CFE738-1-1B model engines, were manufactured from powder metal
material suspected to contain iron inclusion. Further investigation by
the manufacturer determined that the iron inclusion is attributed to
deficiencies in the manufacturing process and may cause reduced
material properties and a lower fatigue life capability, which may
result in structural failure. The manufacturer also informed the FAA
that additional risk assessments determined that there were no failed
events associated with the discovery of this iron inclusion material,
however concluded that replacement of the affected HPT stage 1 and HPT
stage 2 disks is necessary. In the NPRM, the FAA proposed to require
replacement of affected HPT stage 1 and HPT stage 2 disks with parts
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 no comments on the NPRM or on the determination of
the costs.

Conclusion

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 Material Under 1 CFR Part 51

The FAA reviewed CFE Service Bulletin CFE738-72-A8082, dated July
4, 2023, which specifies the affected part and serial numbers of the
HPT stage 1 and stage 2 disks and specifies replacement instructions
for the affected parts. This material 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.

Costs of Compliance

The FAA estimates that this AD affects 29 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

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 adding the following new airworthiness
directive: