DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2020-0745; Product Identifier 2019-CE-030-AD]
RIN 2120-AA64

Airworthiness Directives; Pilatus Aircraft Ltd. Airplanes

AGENCY: Federal Aviation Administration (FAA), Department of
Transportation (DOT).

ACTION: Notice of proposed rulemaking (NPRM).

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SUMMARY: The FAA proposes to adopt a new airworthiness directive (AD)
for Pilatus Aircraft Ltd. Models PC-12, PC-12/45, PC-12/47, and PC-12/
47E airplanes. This proposed AD results from mandatory continuing
airworthiness information (MCAI) originated by an aviation authority of
another country to identify and correct an unsafe condition on an aviation
product. The MCAI describes the unsafe condition as improperly
manufactured horizontal stabilizer rear attachment bolts. If not
corrected, this could lead to fatigue failure of the bolts and loss of
airplane control. The FAA is proposing this AD address the unsafe
condition on these products.

DATES: The FAA must receive comments on this proposed AD by September
21, 2020.

ADDRESSES: You may send comments by any of the following methods:

Federal eRulemaking Portal: Go to https://www.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: U.S. Department of Transportation, Docket
Operations, M-30, West Building Ground Floor, Room W12-140, 1200 New
Jersey Avenue SE, Washington, DC 20590, between 9 a.m. and 5 p.m.,
Monday through Friday, except Federal holidays.

For service information identified in this proposed AD, contact
Pilatus Aircraft Ltd., Customer Technical Support (MCC), P.O. Box 992,
CH-6371 Stans, Switzerland; telephone: +41 (0)41 619 67 74; fax: +41
(0)41 619 67 73; email: Techsupport@pilatus-aircraft.com; internet:
https://www.pilatus-aircraft.com. You may review this referenced
service information at the FAA, Airworthiness Products Section,
Operational Safety Branch, 901 Locust, Kansas City, Missouri 64106. For
information on the availability of this material at the FAA, call (816)
329-4148. It is also available on the internet at https://www.regulations.
gov by searching for and locating Docket No. FAA-2020-0745.

Examining the AD Docket

You may examine the AD docket on the internet at https://www.regulations.
gov by searching for and locating Docket No. FAA-2020-0745;
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 proposed AD, any comments received, and other information. The
street address for Docket Operations is in the ADDRESSES section.
Comments will be available in the AD docket shortly after receipt.

FOR FURTHER INFORMATION CONTACT: Doug Rudolph, Aerospace Engineer, FAA,
General Aviation & Rotorcraft Section, International Validation Branch,
901 Locust, Room 301, Kansas City, Missouri 64106; telephone: (816)
329-4059; fax: (816) 329-4090; email: doug.rudolph@faa.gov.

SUPPLEMENTARY INFORMATION:

Comments Invited

The FAA invites you to send any written relevant data, views, or
arguments about this proposed AD. Send your comments to an address
listed under the ADDRESSES section. Include "Docket No. FAA-2020-0745;
Product Identifier 2019-CE-030-AD" at the beginning of your comments.
The FAA will consider all comments received by the closing date and may
amend this proposed AD 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 we receive, without change, to
https://regulations.gov, including any personal information you
provide. The FAA will also post a report summarizing each substantive
verbal contact it receives about this proposed AD.

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 Doug
Rudolph, Aerospace Engineer, FAA, General Aviation & Rotorcraft
Section, International Validation Branch, 901 Locust, Room 301, Kansas
City, Missouri 64106; telephone: (816) 329-4059; fax: (816) 329-4090;
email: doug.rudolph@faa.gov. Any commentary that the FAA receives which
is not specifically designated as CBI will be placed in the public
docket for this rulemaking.

Discussion

The European Union Aviation Safety Agency (EASA), which is the
Technical Agent for the Member States of the European Community, has
issued EASA AD No. 2019-0129, dated June 6, 2019 (referred to after
this as "the MCAI"), to correct an unsafe condition for Pilatus
Aircraft Ltd. Models PC-12, PC-12/45, PC-12/47, and PC-12/47E
airplanes. The MCAI states:

On the final assembly line, horizontal stabilizer rear
attachment bolts were detected that had not received correct heat
treatment. Subsequent investigation determined that certain parts,
identified by FAUF, were improperly manufactured and consequently
have reduced material properties.

This condition, if not corrected, could lead to a fatigue
failure of an affected part, possibly resulting in loss of control
of the aeroplane.

To address this potential unsafe condition, Pilatus issued the
[service bulletin] SB to provide inspection and replacement
instructions.

For the reason described above, this [EASA] AD requires
replacement of affected parts, and prohibits (re)installation
thereof.

You may obtain further information by examining the MCAI in the AD
docket on the internet at https://www.regulations.gov by searching for
and locating Docket No. FAA-2020-0745.

Related Service Information Under 1 CFR Part 51

The FAA reviewed Pilatus Aircraft Ltd. PC-12 Service Bulletin No.
55-004, dated March 29, 2019. The service information contains
procedures for checking the rear attachment bolts for the horizontal
stabilizer and replacing any defective bolts. 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.

FAA's Determination and Requirements of the Proposed AD

This product has been approved by the aviation authority of another
country, and is approved for operation 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 referenced above. The FAA is proposing this AD
because it evaluated all information and determined the unsafe
condition exists and is likely to exist or develop on other products of
the same type design.

Costs of Compliance

The FAA estimates that this proposed AD would affect 14 products of
U.S. registry. The average labor rate is $85 per work-hour.

The FAA estimates that the proposed actions would take 1.5 work-
hours and require parts costing $5,000, for a cost of $5,127.50 per
product and $71,785 for the U.S. operator fleet.

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 this proposed
regulation:

(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 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 adding the following new airworthiness
directive: