DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2020-0812; Project Identifier MCAI-2020-01317-A]
RIN 2120-AA64

Airworthiness Directives; Pilatus Aircraft Ltd. Airplanes

AGENCY: Federal Aviation Administration (FAA), DOT.

ACTION: Notice of proposed rulemaking (NPRM).

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SUMMARY: The FAA proposes to adopt a new airworthiness directive (AD)
for all Pilatus Aircraft Ltd. (Pilatus) Model PC-24 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 identi-
fies the unsafe condition as the need to revise certain airworthiness
limitations and certification maintenance instructions. The FAA is propos-
ing this AD to address the unsafe condition on these products.

DATES: The FAA must receive comments on this proposed AD by April 26,
2021.

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 Support General Aviation, CH-
6371 Stans, Switzerland; phone: +41 848 24 7 365; email:
techsupport.ch@pilatus-aircraft.com; website: https://www.pilatus-
aircraft.com. You may view this service information at the FAA,
Airworthiness Products Section, Technical Innovation Policy Branch, 901
Locust, Kansas City, MO 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 at https://www.regulations.gov by
searching for and locating Docket No. FAA-2020-0812; 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 NPRM, any comments
received, and other information. The street address for Docket
Operations is listed above.

FOR FURTHER INFORMATION CONTACT: Doug Rudolph, Aviation Safety
Engineer, FAA, General Aviation & Rotorcraft Section, International
Validation Branch, 901 Locust, Room 301, Kansas City, Missouri 64106;
phone: (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 proposal. Send your comments to an address listed
under ADDRESSES. Include "Docket Number FAA-2020-0812; Project
Identifier MCAI-2020-01317-A" at the beginning of your comments. The
most helpful comments reference a specific portion of the proposal,
explain the reason for any recommended change, and include supporting
data. The FAA will consider all comments received by the closing date
and may amend this proposal 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 received, without change, to
https://www.regulations.gov, including any personal information you
provide. The agency will also post a report summarizing each
substantive verbal contact received about this NPRM.

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 AD. Submissions containing CBI should be sent to Doug
Rudolph, Aviation Safety Engineer, FAA, General Aviation & Rotorcraft
Section, International Validation Branch, 901 Locust, Room 301, Kansas
City, Missouri 64106. Any commentary that the FAA receives which is not
specifically designated as CBI will be placed in the public docket for
this rulemaking.

Background

The European Union Aviation Safety Agency (EASA), which is the
Technical Agent for the Member States of the European Union, has issued
EASA AD No. 2020-0202, dated September 22, 2020 (referred to after this
as "the MCAI"), to correct an unsafe condition for Pilatus Model PC-
24 airplanes. The MCAI states:

The airworthiness limitations and certification maintenance
instructions for Pilatus PC-24 aeroplanes, which are approved by
EASA, are currently defined and published in Pilatus PC-24 AMM
[Aircraft Maintenance Manual] Chapter 04-00-00. These instructions
have been identified as mandatory for continued airworthiness.

Failure to accomplish these instructions could result in an
unsafe condition.

Previously, EASA issued AD 2020-0074, [dated March 27, 2020,]
requiring the actions described in the Pilatus PC-24 AMM Chapter 04-
00-00, Document Number 02378 Issue 005 at Revision 14.

Since that AD was issued, Pilatus published the ALS
[Airworthiness Limitations section, at Issue 005 Revision 19], which
contains the following new and/or more restrictive tasks as
specified in Mandatory Structural Inspection Items data module PC24-
AA04-20-0000-00A-000A-A Issue 005 Revision 00:

- AL-27-00-025 and AL-27-00-026: Control column sprocket gear
assembly, and
- AL-27-00-027: Control wheel column assembly.

In addition, Airworthiness Limitations Description data module
PC24-A-A04-00-0000-00A-040A-A Issue 008 Revision 00 includes:

- The new limit of validity following the completion of the Full
Scale Fatigue Test, and
- Usage assumptions/conditions for operations on unpaved and grass
runaways.

EASA AD No. 2020-0074, dated March 27, 2020, required revising the
Airworthiness Limitations section (ALS) to correct an error in the
horizontal stabilizer primary trim system secondary power source
operational test. The MCAI retains the requirements of EASA AD No.
2020-0074, dated March 27, 2020, which the MCAI supersedes, and
requires the additional revisions discussed previously. You may examine
the MCAI at https://www.regulations.gov by searching for and locating
Docket No. FAA-2020-0812.

Related Service Information Under 1 CFR Part 51

The FAA reviewed Chapter 4, Airworthiness Limitations, of Pilatus
PC-24 Aircraft Maintenance Manual, data module PC24-A-A04-00-0000-00A-
040A-A, Issue 008, Revision 00, dated May 26, 2020. This service
information contains the parent data module and the new limit of
validity and updates the usage assumptions and conditions for
operations on unpaved and grass runways. This document also contains
the revised subsections with revised maintenance actions.

The FAA also reviewed Pilatus PC-24 Aircraft Maintenance Manual
Horizontal stabilizer primary trim system secondary power source--
Operation test, data module PC24-A-E27-40-0000-01A-320A-A, Issue 007,
Revision 00, dated September 25, 2019. This service information
contains revised procedures for task number AL-27-40-022 in the CMR.

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

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 us of the unsafe condition described in the MCAI and service
information referenced above. The FAA is issuing this NPRM after
determining that the unsafe condition described previously is likely to
exist or develop on other products of the same type design.

Proposed AD Requirements in This NPRM

This proposed AD would require replacing the revised sections of
the ALS described previously into the existing AMM or instructions for
continued airworthiness. Updating the entire ALS, including all
subsections and referenced data modules, would be acceptable for
compliance with this proposed AD. An owner/operator (pilot) may
incorporate the ALS revisions, and the owner/operator must enter
compliance with the applicable paragraphs of the AD into the aircraft
records in accordance with 14 CFR 43.9(a)(1) through (4) and 14 CFR
91.417(a)(2)(v). This is an exception to our standard maintenance
regulations.

Costs of Compliance

The FAA estimates that this proposed AD would affect 42 products of
U.S. registry. The FAA also estimates that it would take about 1 work-
hour per product to comply with the requirements of this proposed AD.
The average labor rate is $85 per work-hour.

Based on these figures, the FAA estimates the cost of the proposed
AD on U.S. operators would be $3,570 or $85 per product.

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) Would not affect intrastate aviation in Alaska, and

(3) Would 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: