DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2020-0917; Project Identifier MCAI-2020-00606-A;
Amendment 39-21467; AD 2021-06-01]
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 adopting a new airworthiness directive (AD) for all
Pilatus Aircraft Ltd. (Pilatus) Model PC-24 airplanes. This AD was
prompted by a report that electronic circuit breakers (ECBs) were found
in a locked state after maintenance, but before flight. This AD
requires revising the airplane flight manual (AFM) to incorporate a
procedure to check for the ECB status. The FAA is issuing this AD to
address the unsafe condition on these products.

DATES: This AD is effective May 4, 2021.
The Director of the Federal Register approved the incorporation by
reference of a certain publication listed in this AD as of May 4, 2021.

ADDRESSES: For service information identified in this final rule,
contact Pilatus Aircraft Ltd., Customer Technical Support (MCC), P.O.
Box 992, CH-6371 Stans, Switzerland; phone: +41 (0)41 619 67 74; fax:
+41 (0)41 619 67 73; email: techsupport.ch@pilatus-aircraft.com;
website: https://www.pilatus-aircraft.com/. You may view this service
information at the FAA, Airworthiness Products Section, Operational
Safety Branch, 901 Locust Street, Kansas City, MO. For information on
the availability of this material at the FAA, call (816) 329-4148. It
is also available at https://www.regulations.gov by searching for and
locating Docket No. FAA-2020-0917.

Examining the AD Docket

You may examine the AD docket at https://www.regulations.gov by
searching for and locating Docket No. FAA-2020-0917; 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.

FOR FURTHER INFORMATION CONTACT: Doug Rudolph, Aviation Safety
Engineer, FAA, General Aviation & Rotorcraft Section, International
Validation Branch, 901 Locust Street, Room 301, Kansas City, MO 64106;
phone: (816) 329-4059; fax: (816) 329-4090; email:
doug.rudolph@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 apply to all Pilatus Model PC-24
airplanes. The NPRM published in the
Federal Register on October 23, 2020 (85 FR 67465). The NPRM was
prompted by MCAI originated by the European Union Aviation Safety
Agency (EASA), which is the Technical Agent for the Member States of
the European Community. EASA has issued EASA AD No. 2020-0096, dated
April 29, 2020 (referred to after this as ``the MCAI''), to correct an
unsafe condition for Pilatus Model PC-24 airplanes. The MCAI states:

An occurrence was reported where, before take-off after
maintenance of a PC-24 aeroplane, some electronic circuit breakers
(ECB) were found in a ``LOCKED'' state.
This condition, if not corrected, could lead to a loss of power
supply to equipment, without indication to the flight crew before
take-off.
To address this potential unsafe condition, Pilatus issued the
AFM [temporary revision] TR, as defined in this [EASA] AD, to
provide operators with the necessary preflight check instructions.
For the reason described above, this [EASA] AD requires
amendment of the AFM.

You may examine the MCAI in the AD docket at https://www.regulations.gov
by searching for and locating Docket No. FAA-2020-0917.
In the NPRM, the FAA proposed to require revising the AFM to
incorporate a procedure to check for the ECB status. The FAA is issuing
this AD to address the unsafe condition on these products.

Discussion of the Final Airworthiness Directive Comments

The FAA received a comment from Pilatus. The following presents the
comment received on the NPRM and the FAA's response to the comment.

Request To Refer to Revised Service Information

Pilatus stated that the temporary revision referenced in the NPRM
has been incorporated into page 4-3-9, dated October 7, 2020, of the
``Before Engine Start'' procedure (4-PF-04), in Section 4 of Pilatus
PC-24 Airplane Flight Manual, Report No. 02371, Issue 003 Revision 03,
dated October 8, 2020 (AFM Revision 03). Pilatus requested that the FAA
change the proposed AD to require using AFM Revision 03 instead of the
temporary revision.
The FAA partially agrees. This AD requires adding the language in
the temporary revision. However, the FAA has added wording to paragraph
(g) of this AD to still allow compliance if later revisions of the AFM
contain language identical to that in the temporary revision, such as
the page referenced by the commenter.

Conclusion

This product has been approved by the aviation authority of another
country and is approved for operations in the United States. Pursuant
to our bilateral agreement with this state of Design Authority, it has
notified the FAA of the unsafe condition described in the MCAI and
service information reference above. The FAA reviewed the relevant
data, considered the comment received, 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
the changes described previously, this AD is adopted as proposed in the
NPRM.

Related Service Information Under 1 CFR Part 51

The FAA reviewed [Pilatus] PC-24 Temporary Revision 02371-016 to
PC-24 Airplane Flight Manual, PC24-A-A15-99-0031-00A-0030A-A, dated
November 1, 2019. The service information contains a step to be added
to the pilot preflight procedures to check the ECB status. 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 the ADDRESSES section.

Costs of Compliance

The FAA estimates that this AD affects 30 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 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: