Document ID: FAA-2020-0857-0007
Agency: faa
Document Type: Proposed Rule
Title: Airworthiness Directives: Pilatus Aircraft Ltd. Airplanes
Posted Date: 2021-03-08T05:00Z

[Federal Register Volume 86, Number 43 (Monday, March 8, 2021)]
[Proposed Rules]
[Pages 13222-13225]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2021-04395]

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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2020-0857; Project Identifier MCAI-2020-00707-A]
RIN 2120-AA64

Airworthiness Directives; Pilatus Aircraft Ltd. Airplanes

AGENCY: Federal Aviation Administration (FAA), DOT.

ACTION: Supplemental notice of proposed rulemaking (SNPRM).

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SUMMARY: The FAA is revising a notice of proposed rulemaking (NPRM) to 
supersede Airworthiness Directive (AD) 2014-25-04, which applies to 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. 
This action revises the NPRM by adding an eddy current inspection of 
each fuselage wing fitting if an earlier version of the service 
information was accomplished. The FAA is proposing this AD to address 
the unsafe condition on these products. Since these actions would 
impose an additional burden over those in the NPRM, the FAA is 
requesting comments on this SNPRM.

DATES: The FAA must receive comments on this SNPRM by April 22, 2021.

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: U.S. Department of Transportation, Docket 
Operations, M-30, West Building Ground Floor, Room W12-140, 1200 New 
Jersey Avenue SE, Washington, DC, between 9 a.m. and 5 p.m., Monday 
through Friday, except Federal holidays.
    For service information identified in this SNPRM, contact Pilatus 
Aircraft Ltd., Customer Support General Aviation, CH-6371 Stans, 
exception occurred on : 2021-04395.htm
exception occurred on : 2021-04395.htm
Switzerland; phone: +41 848 24 7 365; email: aircraft.com">[email protected]aircraft.com; website: 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, 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 on the internet 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 
the NPRM, this SNPRM, 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, MO 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 No. FAA-2020-0857; Project Identifier 
MCAI-2020-00707-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 
the 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 proposed AD.

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 SNPRM 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 SNPRM, 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 SNPRM. 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, MO 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 FAA issued an 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 applies 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 requires incorporating revised airworthiness limitations 
into the aircraft maintenance manual (AMM) for your FAA-approved 
maintenance program.
    The NPRM published in the Federal Register on October 2, 2020 (85 
FR 62266). The NPRM was prompted by

[[Page 13223]]

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 No. 2020-0120, dated May 27, 2020 (EASA AD 2020-0120). EASA AD 2020-
0120 states that revised airworthiness limitations for the subject 
airplanes introduce new data modules that require non-destructive 
visual and eddy current inspections instead of a previous requirement 
for the fluorescent dye-penetrant method. In the NPRM, the FAA proposed 
to require incorporating the new airworthiness limitations (revision 
29) and performing an eddy current inspection of the fuselage wing 
fittings and wing-to-fuselage fittings.

Actions Since the NPRM Was Issued

    Since the FAA issued the NPRM, EASA superseded EASA AD 2020-0120 
and issued EASA AD No. 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 has 
revised the airworthiness limitations (revision 30) 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 
on the internet at https://www.regulations.gov by searching for and 
locating Docket No. FAA-2020-0857.
    This SNPRM was prompted by the FAA's determination that the revised 
airworthiness limitations and new inspection procedures are necessary, 
in addition to the new life limits proposed in the NPRM. The FAA is 
proposing this AD to address reduced airplane controllability due to 
possible loss of structural integrity of certain parts.

Comments

    The FAA received a comment from Pilatus. The following presents the 
comment received on the NPRM and the FAA's response to that comment.

Request to Reference Latest Service Information

    Pilatus requested that FAA revise the NPRM to require using Pilatus 
PC-6 Aircraft Maintenance Manual Document Number 01975, Revision 30, 
dated October 30, 2020; and Pilatus PC-6 Airworthiness Limitations 
Document Number 02334, Revision 10, dated October 30, 2020. In support 
of its request, Pilatus stated the installation procedure in the 
service information specified in the NPRM is incorrect. Pilatus also 
stated that it has added a note to the airworthiness limitations 
section indicating the data module procedure has been corrected and 
specifying a repeat of the action if it was last done in accordance 
with the prior service information.
    The FAA agrees. After Pilatus submitted its comment, EASA issued 
the MCAI to require the revised service information, as described 
previously. In this SNPRM, the FAA proposes to require the latest 
service information.

Related Service Information Under 1 CFR Part 51

    Pilatus issued 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.
    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 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 pertinent information and determined an 
unsafe condition exists and is likely to exist or develop on other 
products of the same type design.
    Certain changes described above expand the scope of the NPRM. As a 
result, it is necessary to reopen the comment period to provide 
additional opportunity for the public to comment on this SNPRM.

Proposed Requirements of This SNPRM

    This proposed AD would retain none of the requirements of AD 2014-
25-04. This proposed AD would require revising the airworthiness 
limitation section of the existing AMM or instructions for continued 
airworthiness to incorporate new airworthiness limitations. The revised 
limitations include an eddy current inspection of the fuselage wing 
fittings and wing-to-fuselage fittings. This proposed AD would also 
require, within 50 hours time-in-service (TIS) for certain bushes, 
performing an eddy current inspection of the fuselage wing fittings and 
wing-to-fuselage fittings and replacing the bush on the fuselage wing 
fittings using grease. Lastly, this proposed AD would require 
performing the eddy current inspection of the fuselage wing fittings 
and wing-to-fuselage fittings first within 1,100 hours TIS or 12 months 
(whichever occurs first), and thereafter at the intervals specified in 
the revised limitations.
    This proposed AD would require revisions to the airworthiness 
limitations section (ALS) of an operator's maintenance documents to 
include new inspections. Compliance with the airworthiness limitations 
section is required by 14 CFR 91.403(c).

Costs of Compliance

    The FAA estimates that this AD, if adopted as proposed, would 
affect 30 airplanes of U.S. registry. The FAA estimates the following 
costs to comply with this proposed AD:

[[Page 13224]]

                                                 Estimated Costs
----------------------------------------------------------------------------------------------------------------
                                                                                                 Cost on U.S.
              Action                    Labor cost        Parts cost     Cost per  product        operators
----------------------------------------------------------------------------------------------------------------
ALS revision.....................  1 work-hour x $85                $0  $85................  $2,550.
                                    per hour = $85.
Eddy current inspection of the     7 work-hours x $85           $1,860  $2,455 per           $73,650 per
 fuselage wing fittings and         per hour = $595.                     inspection cycle.    inspection cycle.
 wing[dash]to[dash]fuselage
 fittings.
----------------------------------------------------------------------------------------------------------------

    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 
and installation:

                                               On-Condition Costs
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                                                                                                     Cost per
                    Action                                 Labor cost               Parts cost        product
----------------------------------------------------------------------------------------------------------------
Visual and eddy current inspection and          7 work-hours x $85 per hour =             $1,860          $2,455
 installation for certain bushes.                $595.
----------------------------------------------------------------------------------------------------------------

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

0
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]

0
2. The FAA amends Sec.  39.13 by:
0
a. Removing Airworthiness Directive (AD) 2014-25-04, Amendment 39-18045 
(79 FR 73803, December 12, 2014); and
0
b. Adding the following new AD:

Pilatus Aircraft Limited: Docket No. FAA-2020-0857; Project 
Identifier MCAI-2020-00707-A.

(a) Comments Due Date

    The FAA must receive comments on this airworthiness directive 
(AD) by April 22, 2021.

(b) Affected Airworthiness Directives (ADs)

    This AD replaces AD 2014-25-04, Amendment 39-18045 (79 FR 73803, 
December 12, 2014) (AD 2014-25-04).

(c) Applicability

    This AD applies to Pilatus Aircraft Limited 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, all serial numbers, certificated in any 
category.

    Note 1 to paragraph (c): These airplanes may also be identified 
as Fairchild Republic Company airplanes, Fairchild Industries 
airplanes, Fairchild Heli Porter airplanes, or Fairchild-Hiller 
Corporation airplanes.

(d) Subject

    Air Transport Association (ATA) of America Code 05, Time Limits/
Maintenance Checks.

(e) Reason

    This AD was prompted by a determination that new and more 
restrictive airworthiness limitations, new life limits, and new 
inspection procedures are necessary. The FAA is issuing this AD to 
address reduced airplane controllability due to possible loss of 
structural integrity of certain parts.

(f) Airworthiness Limitations Revision

    Unless already done, before further flight, comply with the 
actions specified in paragraphs (f)(1) through (3) of this AD.
    (1) For Models PC-6/B2-H2 and PC-6/B2-H4 airplanes, revise the 
airworthiness limitations section (ALS) of the existing maintenance 
manual or instructions for continued airworthiness (ICA) for your 
airplane as follows:
    (i) Replace Section 04-00-00 with 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.
    (ii) Add (or replace, if applicable) 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.
    (iii) Add Section 57-00-03, Wing to Fuselage Fittings--
Inspection/Check, of the Pilatus PC-6 Aircraft Maintenance Manual 
Document No. 01975, Revision 29, dated February 28, 2020.
    (2) For all airplanes specified in paragraph (c) of this AD 
except Models PC-6/B2-H2 and PC-6/B2-H4 airplanes, revise the ALS of

[[Page 13225]]

the existing maintenance manual or ICA for your airplane as follows:
    (i) Replace the ALS with the Airworthiness Limitations Section 
of Pilatus PC-6 Airworthiness Limitations Document No. 02334, 
Revision 10, dated October 30, 2020.
    (ii) Add (or replace, if applicable) Appendix K, Fuselage Wing 
Fittings--Inspection/Check, of Pilatus PC 6 Airworthiness 
Limitations Document No. 02334, Revision 10, dated October 30, 2020.
    (iii) Add Appendix L, Wing to Fuselage Fittings--Inspection/
Check, of Pilatus PC 6 Airworthiness Limitations Document No. 02334, 
Revision 9, dated March 6, 2020.
    (3) For all airplanes specified in paragraph (c) of this AD, 
after revising the ALS as required by paragraphs (f)(1) and (2) of 
this AD, remove from service each part that has reached or exceeded 
its new life limit.

(g) Inspections and Replacement

    (1) For airplanes with a bush part number (P/N) 6100.0020.01 
that has been bonded as specified in Section 53-00-01, Fuselage Wing 
Fittings--Inspection/Check, of Pilatus PC-6 Aircraft Maintenance 
Manual Document No. 01975, Revision 29, dated February 28, 2020; or 
Appendix K, Fuselage Wing Fittings--Inspection/Check, of Pilatus PC-
6 Airworthiness Limitations Document No. 02334, Revision 9, dated 
March 6, 2020: Within 50 hours time-in-service (TIS) after the 
effective date of this AD, perform a visual and eddy current 
inspection of each fuselage wing fitting on fuselage Frame 3, remove 
bush P/N 6100.0020.01 from service, and install a new (zero hours 
TIS) bush P/N 6100.0020.01 into Frame 3 with grease by using the 
procedures specified in paragraph (f)(1)(ii) or (f)(2)(ii) of this 
AD, as applicable to your airplane.
    (2) Unless already done, within 1,100 hours TIS after the 
effective date of this AD or within 12 months after the effective 
date of this AD, whichever occurs first, perform an eddy current 
inspection of each fuselage wing fitting and each wing-to-fuselage 
fitting using the procedures specified in paragraphs (f)(1)(ii) and 
(iii) of this AD, or paragraphs (f)(2)(ii) and (iii) of this AD, as 
applicable to your airplane. Thereafter, repeat the eddy current 
inspection of each fuselage wing fitting and each wing-to-fuselage 
fitting at the intervals specified in the ALS identified in 
paragraph (f)(1)(i) or (f)(2)(i), as applicable to your airplane.

(h) No Alternative Actions or Intervals

    After the ALS has been revised as required by paragraph (f) of 
this AD, no alternative inspection intervals or procedures may be 
approved, except as provided in paragraph (i) of this AD.

(i) Other FAA AD Provisions

    Alternative Methods of Compliance (AMOCs): The Manager, 
International Validation Branch, FAA, has the authority to approve 
AMOCs for this AD, if requested using the procedures found in 14 CFR 
39.19. Send your request to the person identified in Related 
Information. Before using any approved AMOC, notify your appropriate 
principal inspector, or lacking a principal inspection, the manager 
of the local Flight Standards District Office.

(j) Related Information

    (1) Refer to Mandatory Continuing Airworthiness Information 
(MCAI) European Union Aviation Safety Agency (EASA) AD No. 2020-
0120, dated May 27, 2020, and EASA AD No. 2020-0278, dated December 
14, 2020, for related information. This MCAI may be found in the AD 
docket on the internet at https://www.regulations.gov by searching 
for and locating Docket No. FAA-2020-0857.
    (2) For more information about this AD, contact Doug Rudolph, 
Aviation Safety Engineer, FAA, General Aviation & Rotorcraft 
Section, International Validation Branch, 901 Locust, Room 301, 
Kansas City, MO 64106; telephone: (816) 329-4059; fax: (816) 329-
4090; email: doug.rudolph@faa.gov.
    (3) For service information identified in this AD, contact 
Pilatus Aircraft Ltd., Customer Support General Aviation, CH-6371 
Stans, Switzerland; telephone: +41 848 24 7 365; email: 
Techsupport@pilatusaircraft.com; internet: https://www.pilatusaircraft.com/en. 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.

    Issued on February 25, 2021.
Gaetano A. Sciortino,
Deputy Director for Strategic Initiatives, Compliance & Airworthiness 
Division, Aircraft Certification Service.
[FR Doc. 2021-04395 Filed 3-5-21; 8:45 am]
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