DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2024-0045; Project Identifier MCAI-2023-01088-A;
Amendment 39-22740; AD 2024-08-07]
RIN 2120-AA64

Airworthiness Directives; Pilatus Aircraft Ltd. Airplanes

AGENCY: Federal Aviation Administration (FAA), DOT.

ACTION: Final rule.

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SUMMARY: The FAA is superseding Airworthiness Directive (AD) 2023-12-
17, which applied to Pilatus Aircraft Ltd. (Pilatus) Model PC-12, PC-
12/45, PC-12/47, and PC-12/47E airplanes. AD 2023-12-17 required revising the
airworthiness limitation section (ALS) of the existing aircraft
maintenance manual (AMM) or Instructions for Continued Airworthiness
(ICA) for your airplane by introducing new and more restrictive
instructions and maintenance tasks as specified in the component
limitations section, which includes repetitive inspections for cracks
in the lower main spar connection of the horizontal stabilizer. Since
the FAA issued AD 2023-12-17, the FAA has determined that new or more
restrictive airworthiness limitations are necessary. This AD requires
revising the ALS of your existing AMM or ICA and your existing approved
maintenance or inspection program, as applicable, 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 June 3, 2024.
The Director of the Federal Register approved the incorporation by
reference of a certain publication listed in this AD as of June 3,
2024.

ADDRESSES:
AD Docket: You may examine the AD docket at regulations.gov under
Docket No. FAA-2024-0045; 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 EASA material, 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 material at the FAA, Airworthiness
Products Section, Operational Safety Branch, 901 Locust, Kansas City,
MO 64106. 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-2024-0045.

FOR FURTHER INFORMATION CONTACT: Doug Rudolph, Aviation Safety
Engineer, FAA, 1600 Stewart Avenue, Suite 410, Westbury, NY 11590;
phone: (816) 329-4059; email: doug.rudolph@faa.gov.

SUPPLEMENTARY INFORMATION:

Background

The FAA issued a notice of proposed rulemaking (NPRM) to amend 14
CFR part 39 to supersede AD 2023-12-17, Amendment 39-22475 (88 FR
42604, July 3, 2023) (AD 2023-12-17). AD 2023-12-17 applied to Pilatus
Model PC-12, PC-12/45, PC-12/47, and PC-12/47E airplanes. AD 2023-12-17
required incorporating new revisions to the ALS of the existing AMM or
ICA for your airplane to establish new or more restrictive
airworthiness limitations that include repetitive inspections for
cracks in the lower main spar connection of the horizontal stabilizer.
The FAA issued AD 2023-12-17 to address cracks in the lower main spar
connection of the horizontal stabilizer and failure of certain parts,
which could result in loss of airplane control.
The NPRM published in the Federal Register on February 2, 2024 (89
FR 7297). The NPRM was prompted by EASA AD 2023-0184, dated October 19,
2023 (EASA AD 2023-0184) (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 new or more restrictive tasks and
limitations have been developed. These new or more restrictive
airworthiness limitations include repetitive eddy current inspections
for cracks in the main landing gear yoke fitting.
You may examine the MCAI in the AD docket at regulations.gov under
Docket No. FAA-2024-0045.
In the NPRM, the FAA proposed to require revising the ALS of your
existing AMM or ICA and your existing approved maintenance or
inspection program, as applicable, as specified in EASA AD 2023-0184.
The FAA is issuing this AD to address failure of certain parts, which
could result in asymmetric main landing gear failure that could lead to
loss of airplane control during take-off, landing, and taxiing
operations. Additionally, the actions required to address the unsafe
condition in AD 2023-12-17 are included in ``the applicable ALS,'' as
defined in EASA AD 2023-0184.

Discussion of Final Airworthiness Directive

Comments

The FAA received comments from two anonymous commenters, an
individual, and the Air Line Pilots Association, International (ALPA).
All commenters supported the NPRM without change.

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,
considered the comments received, and determined that air safety
requires adopting the AD as proposed. Accordingly, the FAA is issuing
this AD to address the unsafe condition on these products. This AD is
adopted as proposed in the NPRM.

Related Service Information Under 1 CFR Part 51

EASA AD 2023-0184 requires certain actions and associated
thresholds and intervals, including life limits and maintenance tasks.
EASA AD 2023-0184 also requires doing corrective actions if any
discrepancy (as defined in ``the applicable ALS'' as defined in EASA AD
2023-0184) is found during accomplishment of any task required by
paragraph (1) of EASA AD 2023-0184 and revising the aircraft
maintenance program (AMP) by incorporating the limitations, tasks, and
associated thresholds and intervals described in ``the applicable ALS''
as defined in EASA AD 2023-0184. 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 ADDRESSES.

Differences Between This AD and the MCAI

Paragraph (1) of EASA AD 2023-0184 requires replacing each
component before exceeding the applicable life limit and within the
identified thresholds and intervals accomplishing all applicable
maintenance tasks as specified in the applicable ALS for that airplane.
Paragraph (2) of EASA AD 2023-0184 requires corrective actions in
accordance with the applicable Pilatus maintenance documentation or
contacting Pilatus for approved instructions and accomplishing those
instructions accordingly. Paragraph (4) of EASA AD 2023-0184 provides
credit for performing actions in accordance with previous revisions of
the Pilatus AMM. Paragraph (5) of EASA AD 2023-0184 explains that after
revision of the AMP, it is not necessary to record accomplishment of
individual actions for demonstration of AD compliance. This AD does not
require compliance with paragraphs (1), (2), (4), and (5) of EASA AD 2023-0184.

Costs of Compliance

The FAA estimates that this AD affects 1,030 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 2023-12-17, Amendment 39-22475 (88
FR 42604, July 3, 2023); and

b. Adding the following new airworthiness directive: