DEPARTMENT OF TRANSPORTATION
Federal Aviation Administration
14 CFR Part 39
[Docket No. FAA-2020-0857; Project Identifier MCAI-2020-00707-A;
Amendment 39-21570; AD 2021-11-08]
Airworthiness Directives; Pilatus Aircraft Ltd. Airplanes
AGENCY: Federal Aviation Administration (FAA), DOT.
ACTION: Final rule.
SUMMARY: The FAA is superseding Airworthiness Directive (AD) 2014-25-04
for all Pilatus Aircraft Ltd. (Pilatus) Model PC-6, PC-6-H1, PC-6-H2,
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, and PC-6/C1-H2
airplanes. AD 2014-25-04 required incorporating revised airworthiness
limitations into the aircraft maintenance manual (AMM) for your FAA-
approved maintenance program. This AD requires incorporating new
airworthiness limitations and an eddy current inspection of each
fuselage wing fitting if an earlier version of the service information
was accomplished. This AD was prompted by a determination that the new
life limits, revised airworthiness limitations, and new inspection
procedures are necessary. The FAA is issuing this AD to address the
unsafe condition on these products.
DATES: This AD is effective July 12, 2021.
The Director of the Federal Register approved the incorporation by
reference of certain publications listed in this AD as of July 12,
ADDRESSES: For service information identified in this final rule,
contact Pilatus Aircraft Ltd., Customer Support General Aviation, CH-
6371 Stans, Switzerland; phone: +41 848 24 7 365; email:
Techsupport@pilatus-aircraft.com; website: https://www.pilatus-aircraft.com/en.
You may view this referenced 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 at https://www.regulations.gov
searching for and locating Docket No. FAA-2020-0857.
Examining the AD Docket
You may examine the AD docket at https://www.regulations.gov by
searching for and locating Docket No. FAA-2020-0857; 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, 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, Aviation Safety
Engineer, FAA, General Aviation & Rotorcraft Section, International
Validation Branch, 901 Locust, Room 301, Kansas City, MO 64106; phone:
(816) 329-4059; fax: (816) 329-4090; email: email@example.com.
The FAA issued a notice of proposed rulemaking (NPRM) to amend 14
CFR part 39 to supersede AD 2014-25-04, Amendment 39-18045 (79 FR
73803, December 12, 2014) (AD 2014-25-04). AD 2014-25-04 applied to all
Pilatus Model PC-6, PC-6-H1, PC-6-H2, 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, and PC-6/C1-H2 airplanes and resulted from
mandatory continuing airworthiness information (MCAI) issued by an
aviation authority of another country to identify and correct an unsafe
condition on an aviation product. AD 2014-25-04 required incorporating
revised airworthiness limitations into the AMM for your FAA-approved
The NPRM published in the Federal Register on October 2, 2020 (85
FR 62266). The NPRM was prompted by a MCAI issued by the European Union
Aviation Safety Agency (EASA), which is the Technical Agent for the
Member States of the European Union. EASA superseded its previous MCAIs
on this unsafe condition with EASA AD 2020-0120, dated May 27, 2020
(EASA AD 2020-0120). The NPRM proposed to require revising the
airworthiness limitation section of the existing maintenance manual or
instructions for continued airworthiness to incorporate new
airworthiness limitations, and performing an eddy current inspection of
the fuselage wing fittings and wing to fuselage fittings.
After the FAA issued the NPRM, EASA superseded EASA AD 2020-0120
and issued EASA AD 2020-0278, dated December 14, 2020 (EASA AD 2020-
0278) (also referred to after this as ``the MCAI''). According to EASA
AD 2020-0278, an installation procedure specified in the service
information identified in the NPRM contained an error and, therefore,
did not adequately address the identified unsafe condition. Pilatus
revised the airworthiness limitations and issued corrected service
information, which includes installing certain bushes using grease
instead of a bonding agent and an additional one-time eddy current
inspection of the fuselage wing fittings and wing-to-fuselage fittings
if the last inspection was performed using an earlier version of the
service information. You may examine the MCAI in the AD docket at
https://www.regulations.gov by searching for and locating Docket No.
The FAA issued a supplemental notice of proposed rulemaking (SNPRM)
to amend 14 CFR part 39 to supersede AD 2014-25-04. The SNPRM published
in the Federal Register on March 8, 2021 (86 FR 13222). The SNPRM
proposed to add an eddy current inspection of each fuselage wing
fitting if an earlier version of the service information was
accomplished. The FAA is issuing this AD to address reduced airplane
controllability due to possible loss of structural integrity of certain
Discussion of the Final Airworthiness Directive
The FAA received no comments on the SNPRM or on the determination
of the costs.
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 reviewed the relevant
data and determined that air safety requires adoption of the AD as
proposed. Accordingly, the FAA is issuing this AD to address the unsafe
condition on these products. This AD is adopted as proposed in the
Related Service Information Under 1 CFR Part 51
Pilatus issued the Airworthiness Limitations Section of PC-6
Airworthiness Limitations Document No. 02334, Revision 10, dated
October 30, 2020; and Section 04-00-00, Airworthiness Limitations of
Chapter 04, Airworthiness Limitations, of the Pilatus PC-6 Aircraft
Maintenance Manual Document No. 01975, Revision 30, dated October 30,
2020. This service information contains airworthiness limitations for
the stabilizer trim actuator, fuselage wing fittings, and wing-to-
fuselage fittings. These documents are distinct since they apply to
different airplane models.
Pilatus also issued Section 53-00-01, Fuselage Wing Fittings--
Inspection/Check, of the Pilatus PC-6 Aircraft Maintenance Manual
Document No. 01975, Revision 30, dated October 30, 2020; Section 57-00-
03, Wing to Fuselage Fittings--Inspection/Check, of the PC-6 Aircraft
Maintenance Manual Document No. 01975, Revision 29, dated February 28,
2020; Appendix K, Fuselage Wing Fittings--Inspection/Check, of the PC-6
Airworthiness Limitations Document No. 02334, Revision 10, dated
October 30, 2020; and Appendix L, Wing to Fuselage Fittings--
Inspection/Check, of the PC-6 Airworthiness Limitations Document No.
02334, Revision 9, dated March 6, 2020. This service information
specifies procedures for repetitive eddy current inspections of the
fuselage wing fittings and wing-to-fuselage fittings and, if necessary,
installing the bush on the fuselage wing fittings using grease. These
documents are distinct since they apply to different airplane models.
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 affects 30 airplanes of U.S.
registry. The FAA estimates the following costs to comply with this AD:
||1 work-hour x $85 per hour =
|Eddy current inspection of the
fuselage wing fittings and wing-to-fuselage fittings
||7 work-hours x $85 per
hour = $595
The FAA estimates the following costs
to do the inspections and
installation that would be required if an earlier version of the
service information has been accomplished. The agency has no way of
determining the number of aircraft that might need these inspections
|Visual and eddy current inspection
and installation for certain
||7 work-hours x $85 per hour =
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.
The FAA determined that 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 that this AD:
(1) Is not a ``significant regulatory action'' under Executive
(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
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:
a. Removing Airworthiness Directive 2014-25-04, Amendment 39-18045 (79
FR 73803, December 12, 2014), and
b. Adding the following new airworthiness directive: