DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2020-0719; Project Identifier 2019-CE-041-AD; Amendment
39-21313; AD 2020-22-17]
RIN 2120-AA64

Airworthiness Directives; Pilatus Aircraft Ltd. Airplanes

AGENCY: Federal Aviation Administration (FAA), DOT.

ACTION: Final rule.

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SUMMARY: The FAA is adopting a new airworthiness directive (AD) for
certain Pilatus Aircraft Ltd. (Pilatus) Model PC-24 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. The MCAI identifies
the unsafe condition as movement of the aft fuel pipe within the
coupling, which can cause damage to the O-rings and lead to a fuel
leak, fuel fire or explosion, and consequent loss of control of the
airplane. This AD requires replacing and prohibits installing affected
parts. The FAA is issuing this AD to address the unsafe condition on
these products.

DATES: This AD is effective December 14, 2020.
The Director of the Federal Register approved the incorporation by
reference of a certain publication listed in this AD as of December 14,
2020.

ADDRESSES: For service information identified in this final rule,
contact Pilatus Aircraft Ltd., Customer Support General Aviation, CH-
6371 Stans, Switzerland, telephone: +41 848 24 7 365, techsupport.ch@
pilatus-aircraft.com, https://www.pilatus-aircraft.com.
You may view this service information at the FAA, Airworthiness
Products Section, Operational Safety Branch, 901 Locust, Kansas City,
MO 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-2020-0719.

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-
0719; 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 mandatory continuing airworthiness information
(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; telephone: (816)
329-4059; fax: (816) 329-4090; email: doug.rudolph@faa.gov.

SUPPLEMENTARY INFORMATION:

Discussion

The FAA issued a notice of proposed rulemaking (NPRM) to amend 14
CFR part 39 by adding an AD that would apply to Pilatus Model PC-24
airplanes with a certain part-numbered flexible saddle clamp installed
between frame 34 and 36. The NPRM published in the Federal Register on
July 30, 2020 (85 FR 45810). The NPRM proposed to require actions to
correct the unsafe condition on the specified products and was prompted
by MCAI originated by the European Union Aviation Safety Agency (EASA),
which is the Technical Agent for the Member States of the European
Union. EASA issued AD No. 2019-0240, dated September 25, 2019 (referred
to after this as ``the MCAI''), which states:

An occurrence was reported where, during maintenance, when
system pressure was applied to a motive-flow fuel pipe, the aft fuel
pipe was found to move to the end stop within the coupling. When
system pressure was released, the aft fuel pipe returned to its
point of origin. This movement can cause damage to the O-rings.
This condition, if not corrected, could lead to a fuel leak and
consequently a fuel contamination of the rear fuselage, which, in
combination with an ignition source in this
area, could possibly result in a fuel fire or fuel vapour explosion
and consequent loss of the aeroplane.
To address this potential unsafe condition, Pilatus issued the
[service bulletin] SB to provide modification instructions.
For the reason described above, this [EASA] AD requires
replacement of affected parts with serviceable parts, as defined in
this AD, and prohibits (re-) installation of affected parts.

You may examine the MCAI on the internet at https://www.regulations.gov
by searching for and locating Docket No. FAA-2020-0719.

Comments

The FAA gave the public the opportunity to participate in
developing this final rule. The FAA received no comments on the NPRM or
on the determination of the cost to the public.

Conclusion

The FAA reviewed the relevant data and determined that air safety
and the public interest require adopting this final rule as proposed.

Related Service Information Under 1 CFR Part 51

The FAA reviewed Pilatus PC-24 Service Bulletin No. 28-002, dated
May 3, 2019. The service information contains procedures for replacing
the two flexible saddle clamps on the left-hand (LH) motive-flow fuel
pipe and the two flexible saddle clamps on the right-hand (RH) motive-
flow fuel pipe with fixed saddle clamps. This service information also
contains procedures for replacing the four O-rings on the LH and RH
motive-flow fuel pipes. 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.

Costs of Compliance

The FAA estimates that this AD will affect 16 products of U.S.
registry. The FAA also estimates that it will take about 7 work-hours
per product to comply with the requirements of this AD. The average
labor rate is $85 per work-hour. Required parts will cost about $5,000
per product.
Based on these figures, the FAA estimates the cost of the AD on
U.S. operators will be $89,520 or $5,595 per product.
According to the manufacturer, all or some of the costs of this AD
may be covered under warranty, thereby reducing the cost impact on
affected individuals. The FAA does not control warranty coverage for
affected individuals. As a result, the FAA has included all costs in
this cost estimate.

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.

Adoption of 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: