DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2020-0849; Project Identifier MCAI-2020-01036-A;
Amendment 39-21374; AD 2020-26-19]
RIN 2120-AA64

Airworthiness Directives; Pilatus Aircraft Ltd. Airplanes

AGENCY: Federal Aviation Administration (FAA), DOT.

ACTION: Final rule.

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

SUMMARY: The FAA is adopting a new airworthiness directive (AD) for all
Pilatus Aircraft Ltd. Model PC-7 airplanes. This 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. This AD requires revising the
Airworthiness Limitations section (ALS) of the existing aircraft
maintenance manual (AMM) to introduce new mandatory repetitive
inspections for the flap pivot arm assemblies and for certain wing
angle brackets, and to implement a change to the Oxygen cylinder and
pressure reducer task item. The FAA is issuing this AD to address the
unsafe condition on these products.

DATES: This AD is effective March 29, 2021.
The Director of the Federal Register approved the incorporation by
reference of a certain publication listed in this AD as of March 29,
2021.

ADDRESSES: For service information identified in this final rule,
contact Pilatus Aircraft Ltd., CH-6371, 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; email: techsupport@pilatus-aircraft.com;
website: https://www.pilatus-aircraft.comen/. 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.
It is also available at https://www.regulations.gov by searching for
and locating Docket No. FAA-2020-0849.

Examining the AD Docket

You may examine the AD docket 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 final rule, the
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, Aerospace 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:

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 Aircraft
Ltd. Model PC-7 airplanes. The NPRM published in the Federal Register
on September 24, 2020 (85 FR 60097). The NPRM was prompted by MCAI
originated by the Federal Office for Civil Aviation (FOCA), which is
the aviation authority for Switzerland. FOCA has issued FOCA AD HB-
2020-007, dated July 23, 2020 (referred to after this as 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 at https://www.regulations.gov by
searching for and locating Docket No. FAA-2020-0849.
The NPRM proposed to require revising the ALS of the existing AMM
to introduce the new mandatory repetitive inspections for the flap
pivot arm assemblies and for certain wing angle brackets, and to
implement a change to the Oxygen cylinder and pressure reducer task
item. The FAA is issuing this AD to address the unsafe condition on
these products.

Comments

The FAA received no comments on the NPRM or on the determination of
the costs.

Conclusion

The FAA reviewed the relevant data and determined that air safety
and the public interest require adopting this AD as proposed.
Accordingly, the FAA is issuing this AD to address the unsafe condition
on these products. Except for minor editorial changes, this AD is
adopted as proposed in the NPRM.

Related Service Information Under 1 CFR Part 51

Pilatus Aircraft Ltd. has issued Section 05-10-10, ``Lifed and
Overhauled Components,'' dated June 30, 2020, of Chapter 05, Time
Limits/Maintenance Checks, of the Pilatus PC-7 Maintenance Manual. This
document provides updated limitations, inspections, and procedures for
the airworthiness limitations in chapter 5 of the existing AMM. This
service information contains 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 MCAI requires 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. This AD only
requires Section 05-10-10, ``Lifed and Overhauled Components,'' dated
June 30, 2020, of Chapter 05, Time Limits/Maintenance Checks, of the
Pilatus PC-7 Maintenance Manual, because it is the only mandatory
section of the ALS for the U.S. type certificate.

Costs of Compliance

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

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: