DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2020-0849; Project Identifier MCAI-2020-01036-A]
RIN 2120-AA64

Airworthiness Directives; Pilatus Aircraft Ltd. Airplanes

AGENCY: Federal Aviation Administration (FAA), DOT.

ACTION: Notice of proposed rulemaking (NPRM).

-----------------------------------------------------------------------

SUMMARY: The FAA proposes to adopt a new airworthiness directive (AD)
for all Pilatus Aircraft Ltd. Model PC-7 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 the need to revise the Airworthiness Limitations
section (ALS) of the existing aircraft maintenance manual (AMM) to intro-
duce new mandatory repetitive inspections for the flap pivot arm assem-
blies and for certain wing angle brackets, and to implement a change to
the Oxygen cylinder and pressure reducer task item. The FAA is proposing
this AD to address the unsafe condition on these products.

DATES: The FAA must receive comments on this proposed AD by November 9,
2020.

ADDRESSES: You may send comments, using the procedures found in 14 CFR
11.43 and 11.45, 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: Deliver to Mail address above between 9
a.m. and 5 p.m., Monday through Friday, except Federal holidays.

For service information identified in this NPRM, 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/en. You may view this 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.

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-2020-0849;
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. 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 participate in this rulemaking by submitting
written comments, data, or views about this proposal. The most helpful
comments reference a specific portion of the proposal, explain the
reason for any recommended change, and include supporting data. To
ensure the docket does not contain duplicate comments, commenters
should send only one copy of written comments, or if comments are filed
electronically, commenters should submit only one time. Send your
comments to an address listed under the ADDRESSES section. Include
"Docket No. FAA-2020-0849; Project Identifier MCAI-2020-01036-A" at
the beginning of your 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, as well
as a report summarizing each substantive public contact with FAA
personnel concerning this proposed rulemaking. Before acting on this
proposal, the FAA will consider all comments received by the closing
date for comments. The FAA will consider comments filed after the
comment period has closed if it is possible to do so without incurring
expense or delay. The FAA may change this NPRM because of those
comments.

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 the
person identified in the FOR FURTHER INFORMATION CONTACT section. 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 Federal Office of Civil Aviation (FOCA), which is the aviation
authority for Switzerland, has issued FOCA AD HB-2020-007, dated July
23, 2020 (referred to after this as the Mandatory Continuing
Airworthiness Information, or "the MCAI"), to correct an unsafe
condition with new mandatory instructions for continued airworthiness
for all Pilatus Aircraft Ltd. Model PC-7 airplanes. The MCAI states:

The airworthiness limitations and certification maintenance
instructions for Pilatus PC-7 aeroplanes, which are approved by
FOCA, are currently defined and published in the Pilatus PC-7 AMM
Chapter 5. These instructions have been identified as mandatory for
continued airworthiness.

Failure to accomplish these instructions could result in an
unsafe condition [discrepancies of life-limited and overhauled
components, which could result in reduced structural integrity and
system reliability of the airplane].

Previously, FOCA issued AD HB-2019-004 (later corrected) to
require implementation of the maintenance tasks and airworthiness
limitations as specified in Pilatus PC-7 AMM Document Number 01715,
or Document Number 02416, both at issue 44, as applicable. [These
tasks included the added wing angle bracket at rib 23 repetitive
inspections.]

Since that AD was issued, Pilatus amended the ALS, as defined in
this AD, to introduce new mandatory repetitive inspection for the
flap pivot arm assemblies and a change to the Oxygen cylinder and
pressure reducer task (Chapter 35--Oxygen) to remove the reference
to the part numbers.

For the reason described above, this [Swiss] AD retains the
requirements of FOCA AD HB-2019-004 including its correction, which
is superseded, and requires accomplishment of the actions specified
in the ALS.

You may examine the MCAI in the AD docket on the internet at
https://www.regulations.gov by searching for and locating Docket No.
FAA-2020-0849.

Related Service Information Under 1 CFR Part 51

Pilatus Aircraft Ltd. has issued Section 05-10-10, "Lifed and
Overhauled Components," of Chapter 05, Time Limitations, of the
Pilatus PC-7 Maintenance Manual, dated June 30, 2020. This document
provides updated limitations, inspections, and procedures for the air-
worthiness limitations in chapter 5 of the existing AMM. This service
information describes new mandatory repetitive inspections for the flap
pivot arm assemblies and for the wing angle brackets on middle rib 23,
and a change to the Oxygen cylinder and pressure reducer task item to
remove the reference to the part numbers.

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.

Differences Between This AD and the MCAI

The FOCA AD is requiring incorporating all of the updated Chapter
05-00-00 for the Swiss State of Design type certificate because they
deem the complete chapter 5 as the mandatory ALS of the PC-7 AMM. The
FAA is only requiring Section 05-10-10, "Lifed and Overhauled
Components," of Chapter 05, Time Limitations, of the Pilatus PC-7
Maintenance Manual, dated June 30, 2020, because it is the only
mandatory section of the ALS for the U.S. type certificate.

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 the FAA's bilateral agreement with the State of Design Authority,
the FAA has been notified of the unsafe condition described in the MCAI
and service information referenced above. The FAA is proposing this AD
because the FAA evaluated all the relevant information and determined
the unsafe condition described previously is likely to exist or develop
on other products of the same type design.

Proposed Requirements of This NPRM

This proposed AD would require revising the airworthiness
limitation section of the existing maintenance manual or instructions
for continued airworthiness to incorporate new airworthiness
limitations. An owner/operator (pilot) may incorporate the revisions to
the AMM, 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). A pilot
may perform these actions because they can be performed equally well by
a pilot or a mechanic. This is an exception to our standard maintenance
regulations.

This proposed AD would require revisions to certain operator
maintenance documents to include new actions (e.g., inspections).
Compliance with these actions is required by 14 CFR 91.403(c). For
airplanes that have been previously modified, altered, or repaired in
the areas addressed by this proposed AD, the operator may not be able
to accomplish the actions described in the revisions. In this
situation, to comply with 14 CFR 91.403(c), the operator must request
approval for an alternative method of compliance according to paragraph
(h) of this proposed AD.

Costs of Compliance

The FAA estimates that this proposed AD affects 18 airplanes of
U.S. registry. The FAA estimates the following costs to comply with
this proposed AD:

Estimated Costs for Required 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.

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 (AD):