DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2019-0240; Product Identifier 2018-CE-057-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: We propose to adopt a new airworthiness directive (AD) for
certain Pilatus Aircraft Ltd. Models PC-6, PC-6/350, PC-6/350-H1, PC-6/
350-H2, PC-6/A, PC-6/A-H1, PC-6/A-H2, PC-6/B-H2, PC-6/B1-H2, PC-6/B2-
H2, PC-6/B2-H4, PC-6/C-H2, PC-6/C1-H2, PC-6-H1, and PC-6-H2 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 flap actuator taper
pins that were not swaged during the manufacturing process. We are issuing
this proposed AD to require actions to address the unsafe condition on
these products.

DATES: We must receive comments on this proposed AD by May 20, 2019.

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

Federal eRulemaking Portal: Go to http://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; phone: +41 (0)41 619 67 74; fax: +41 (0)41
619 67 73; email: techsupport@pilatus-aircraft.com; internet: http://
www.pilatus-aircraft.com. You may review this referenced service
information at the FAA, Policy and Innovation Division, 901 Locust,
Kansas City, Missouri 64106. For information on the availability of
this material at the FAA, call (816) 329-4148.

Examining the AD Docket

You may examine the AD docket on the internet at http://www.regulations.
gov by searching for and locating Docket No. FAA-2018-
0240; 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, the regulatory evaluation, any comments received, and
other information. The street address for Docket Operations (telephone
(800) 647-5527) 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,
Small Airplane Standards 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

We invite 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-2018-0240;
Product Identifier 2018-CE-057-AD" at the beginning of your comments.
We specifically invite comments on the overall regulatory, economic,
environmental, and energy aspects of this proposed AD. We will consider
all comments received by the closing date and may amend this proposed
AD because of those comments.

We will post all comments we receive, without change, to http://
regulations.gov, including any personal information you provide. We
will also post a report summarizing each substantive verbal contact we
receive about this proposed AD.

Discussion

The European Aviation Safety Agency (EASA), which is the Technical
Agent for the Member States of the European Community, has issued EASA
AD No. 2018-0235, dated November 5, 2018 (referred to after this as
"the MCAI"), to correct an unsafe condition for Pilatus Aircraft
Limited Models PC-6, PC-6/350, PC-6/350-H1, PC-6/350-H2, PC-6/A, PC-6/
A-H1, PC-6/A-H2, PC-6/B-H2, PC-6/B1-H2, PC-6/B2-H2, PC-6/B2-H4, PC-6/C-
H2, PC-6/C1-H2, PC-6-H1, and PC-6-H2 airplanes. The MCAI states:

During a recent overhaul, two new flap actuators were found to
have taper pins installed that, apparently, had not been swaged.
Investigation results identified that the taper pins had been
incorrectly swaged during the manufacturing process.

This condition, if not detected and corrected, could lead to
loss of one or both taper pins, consequent asymmetric flap
deployment or flap surface flutter, possibly resulting in loss of
control of the aeroplane.

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

For the reason described above, this [EASA] AD requires a one-
time inspection of the taper pins of the affected parts for correct
installation and, depending on findings, accomplishment of
applicable corrective action(s). This [EASA] AD also requires
inspection of, and, depending on findings, corrective action(s) on,
affected parts held as spare, prior to installation.

You may examine the MCAI on the internet at http://www.regulations.gov
by searching for and locating Docket No. FAA-2018-0240.

Related Service Information Under 1 CFR Part 51

Pilatus Aircraft Ltd. has issued Pilatus PC-6 Service Bulletin No.
27-005, dated July 2, 2018. The service information contains procedures
for removing and inspecting the flap actuator assemblies and pushrod
assemblies, modifying or replacing the taper pins if necessary, and
reinstalling the assemblies. 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, they
have notified us of the unsafe condition described in the MCAI and
service information referenced above. We are proposing this AD because
we 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

We estimate that this proposed AD will affect 30 products of U.S.
registry. We also estimate that it would take about 12 work-hours per
product to comply with the basic inspection requirements of this
proposed AD. The average labor rate is $85 per work-hour.

Based on these figures, we estimate the cost of the proposed AD on
U.S. operators to be $30,600, or $1,020 per product.

In addition, we estimate that any necessary follow-on modification
or replacement actions would require parts costing $30,000, for a cost
of $1,000 per product. We have no way of determining the number of
products that may need these actions.

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.

We are 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 rule-
making action.

This AD is issued in accordance with authority delegated by the
Executive Director, Aircraft Certification Service, as authorized by
FAA Order 8000.51C. In accordance with that order, issuance of ADs is
normally a function of the Compliance and Airworthiness Division, but
during this transition period, the Executive Director has delegated the
authority to issue ADs applicable to small airplanes, gliders,
balloons, airships, domestic business jet transport airplanes, and
associated appliances to the Director of the Policy and Innovation
Division.

Regulatory Findings

We 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) Is not a "significant rule" under the DOT Regulatory Policies
and Procedures (44 FR 11034, February 26, 1979),

(3) Will not affect intrastate aviation in Alaska, and

(4) 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 (AD):