[Federal Register Volume 86, Number 178 (Friday, September 17, 2021)]
[Proposed Rules]
[Pages 51835-51838]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2021-19961]


 ========================================================================
 Proposed Rules
                                                 Federal Register
 ________________________________________________________________________
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 This section of the FEDERAL REGISTER contains notices to the public of 
 the proposed issuance of rules and regulations. The purpose of these 
 notices is to give interested persons an opportunity to participate in 
 the rule making prior to the adoption of the final rules.
 
 ========================================================================
 

  Federal Register / Vol. 86, No. 178 / Friday, September 17, 2021 / 
Proposed Rules  

[[Page 51835]]



DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2021-0786; Project Identifier MCAI-2021-00429-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 supersede Airworthiness Directive (AD) 
2012-06-16, which applies to all Pilatus Aircraft Ltd. (Pilatus) Models 
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 2012-06-16 requires installing a new 
rudder and elevator locking screw and modifying the installation of the 
rudder and elevator hinge bolt. Since the FAA issued AD 2012-06-16, the 
European Union Aviation Safety Agency (EASA) superseded its mandatory 
continuing airworthiness information (MCAI) to correct an unsafe 
condition on these products. This proposed AD would not retain any 
actions required by AD 2012-06-16 and would require inspecting and 
modifying the rudder, elevator, and right-hand (RH) aileron hinge bolt 
installations. 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 1, 
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: 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 Support General Aviation, CH-6371 Stans, 
Switzerland; phone: +41 848 24 7 365; email: aircraft.com">techsupport.ch@pilatus-aircraft.com; website: 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.

Examining the AD Docket

    You may examine the AD docket at https://www.regulations.gov by 
searching for and locating Docket No. FAA-2021-0786; 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, the MCAI, 
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: [email protected].

SUPPLEMENTARY INFORMATION:

Comments Invited

    The FAA invites you to send any written relevant data, views, or 
arguments about this proposed AD. Send your comments to an address 
listed under the ADDRESSES section. Include ``Docket No. FAA-2021-0786; 
Project Identifier MCAI-2021-00429-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 NPRM.

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 AD. 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 AD 2012-06-16, Amendment 39-16997 (77 FR 19061, 
March 30, 2012) (AD 2012-06-16) for Pilatus Models 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 2012-06-16 was prompted by MCAI originated by EASA, 
which is the Technical Agent for the Member States of the European 
Union. EASA issued EASA AD 2011-0230, dated December 9, 2011, to 
identify and correct an unsafe condition identified as loose elevator 
and rudder

[[Page 51836]]

hinge bolts caused by incorrect torqueing and locking of the bolts.
    AD 2012-06-16 requires installing a new elevator and rudder locking 
screw and modifying the installation of the elevator and rudder hinge 
bolt. The FAA issued AD 2012-06-16 to prevent in-flight failure of the 
elevator or rudder attachment, which could result in loss of control of 
the airplane.

Actions Since AD 2012-06-16 Was Issued

    Since the FAA issued AD 2012-06-16, EASA superseded EASA AD 2011-
0230, dated December 9, 2011, and issued EASA AD 2021-0098, dated April 
9, 2021 (referred to after this as ``the MCAI''). The MCAI states:

    Occurrences were reported where, on certain PC-6 aeroplanes, the 
elevator or the rudders was lost or partially detached during 
flight. All the occurrences happened on PC-6 aeroplanes in CONFIG 1.
    This condition, if not corrected, could lead to in-flight 
failure of the elevator or rudder attachment, possibly resulting in 
reduced control of the aeroplane.
    To address this potential unsafe condition, Pilatus issued SB 
55-001 (original issue and Revision 1) to provide rework 
instructions for the elevator and rudder hinge bolt locking. 
Consequently, EASA published AD 2011-0230 to require this rework. 
Subsequently, Pilatus issued recommended SB 55-003 (later revised) 
to provide instructions to modify the hinge bolt installation of the 
elevator and rudder. This [service bulletin] SB, being recommended 
only, had no impact on the existing EASA AD.
    Since that [EASA] AD and the recommended Pilatus SB 55-003 were 
published, the latest risk assessment determined that the 
modification of the hinge bolt installation of the elevator, rudder 
and right-hand (RH) aileron installation must be required to reach 
an acceptable level of safety for the affected aeroplanes. 
Consequently, Pilatus issued the SB, as defined in this [EASA] AD, 
to provide instructions to modify the affected aeroplanes into 
CONFIG 2 standard.
    For the reasons described above, this [EASA] AD supersedes EASA 
AD 2011-0230 and requires, for certain aeroplanes, a one-time 
inspection of the elevator and rudder installation, followed by 
repetitive inspections of the elevator and rudder, and, depending on 
findings, accomplishment of applicable corrective action(s). This 
[EASA] AD also requires modification of the elevator, rudder and RH 
aileron hinge bolt installations into CONFIG 2, which is the 
terminating action for the repetitive inspections required by this 
[EASA] AD. Finally, this [EASA] AD prohibits (re)installation of 
affected parts.

    You may examine the MCAI in the AD docket at https://www.regulations.gov by searching for and locating Docket No. FAA-2021-
0786.

Related Service Information Under 1 CFR Part 51

    The FAA reviewed Pilatus PC-6 Service Bulletin (SB) No. 55-005, 
dated February 25, 2021 (Pilatus SB 55-005). The service information 
specifies procedures for repetitively inspecting the hinge bolt 
installations and taking any necessary corrective actions until the 
hinge bolt is modified. Modifying the hinge bolt installation in 
accordance with Pilatus SB 55-005 makes the airplane a CONFIG 2 design. 
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.

Other Related Service Information

    Pilatus also issued Pilatus PC-6 SB No. 55-003, dated November 29, 
2013; Pilatus PC-6 SB No. 55-003, Revision 1, dated December 9, 2014; 
Pilatus PC-6 SB No. 55-003, Revision 2, dated January 19, 2017; and 
Pilatus PC-6 SB No. 55-003, Revision 3, dated November 6, 2017. This 
service information specifies procedures for modifying the hinge bolt 
installations, which makes the airplane a CONFIG 2 design. This service 
information was superseded by Pilatus SB 55-005.

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 this State of Design Authority, 
it has notified the FAA of the unsafe condition described in the MCAI 
and service information referenced above. The FAA is issuing this NPRM 
after determining that the unsafe condition described previously is 
likely to exist or develop on other products of the same type design.

Proposed AD Requirements in This NPRM

    This proposed AD would require accomplishing the actions specified 
in the service information described previously. This proposed AD would 
not retain any actions of AD 2012-06-06.

Costs of Compliance

    The FAA estimates that this AD, if adopted as proposed, would 
affect 50 airplanes of U.S. registry.
    The FAA estimates the following costs to comply with this proposed 
AD:

                                                 Estimated Costs
----------------------------------------------------------------------------------------------------------------
                                                                                                  Cost on U.S.
            Action                  Labor cost            Parts cost         Cost per product      operators
----------------------------------------------------------------------------------------------------------------
Inspecting CONFIG 1 airplanes.  4.5 work-hours x   Not applicable.........  $382.50 per        $19,125 per
                                 $85 per hour =                              inspection cycle.  inspection
                                 $382.50.                                                       cycle.
Modifying from CONFIG 1 to      14 work-hours x    $1,200.................  $2,390...........  $119,500.
 CONFIG 2.                       $85 per hour =
                                 $1,190.
----------------------------------------------------------------------------------------------------------------

    The FAA estimates the following costs to do any necessary 
corrective actions that would be required based on the results of the 
proposed inspection. The FAA has no way of determining the number of 
airplanes that might need these actions:

                                               On-Condition Costs
----------------------------------------------------------------------------------------------------------------
                                                                                                     Cost per
                    Action                                 Labor cost               Parts cost        product
----------------------------------------------------------------------------------------------------------------
Accomplishing corrective actions..............  .5 work-hours x $85 per hour =              $200         $242.50
                                                 $42.50.
----------------------------------------------------------------------------------------------------------------


[[Page 51837]]

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 has 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 that the proposed 
regulation:
    (1) Is not a ``significant regulatory action'' under Executive 
Order 12866,
    (2) Would not affect intrastate aviation in Alaska, and
    (3) Would 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 2012-06-16, Amendment 39-16997 (77 
FR 19061, March 30, 2012); and
0
b. Adding the following new airworthiness directive:

Pilatus Aircraft Ltd.: Docket No. FAA-2021-0786; Project Identifier 
MCAI-2021-00429-A.

(a) Comments Due Date

    The FAA must receive comments on this airworthiness directive 
(AD) by November 1, 2021.

(b) Affected ADs

    This AD replaces AD 2012-06-16, Amendment 39-16997 (77 FR 19061, 
March 30, 2012).

(c) Applicability

    This AD applies to Pilatus Aircraft Ltd. Models 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

    Joint Aircraft System Component (JASC) Codes 2700, Flight 
Control System; 2710, Aileron Control System; 2720, Rudder Control 
System; and 2730, Elevator Control System.

(e) Unsafe Condition

    This AD was prompted by 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 detachment or 
partial detachment of the elevator or rudder in flight. The FAA is 
issuing this AD to prevent failure of the elevator or rudder 
attachment. The unsafe condition, if not addressed, could result in 
loss of control of the airplane.

(f) Compliance

    Comply with this AD within the compliance times specified, 
unless already done.

(g) Definitions

    The following definitions apply for purposes of this AD.
    (1) Group 1 airplanes: Airplanes that have not been modified in 
accordance with Pilatus PC-6 Service Bulletin (SB) No. 55-003, dated 
November 29, 2013 (Pilatus SB 55-003); Pilatus PC-6 SB No. 55-003, 
Revision 1, dated December 9, 2014 (Pilatus SB 55-003R1); Pilatus 
PC-6 SB No. 55-003, Revision 2, dated January 19, 2017 (Pilatus 55-
003R2); Pilatus PC-6 SB No. 55-003, Revision 3, dated November 6, 
2017 (Pilatus 55-003R3); or Pilatus PC-6 SB No. 55-005, dated 
February 25, 2021 (Pilatus SB 55-005).
    (2) Group 2 airplanes: Airplanes that have been modified in 
accordance with Pilatus SB 55-003, SB 55-003R1, SB 55-003R2, Pilatus 
SB 55-003R3; or Pilatus SB 55-005.

(h) Inspect Elevator, Rudder, and RH Aileron Hinge Bolt Installations

    (1) For Group 1 airplanes: Within 14 days after the effective 
date of this AD, inspect the elevator, rudder, and RH aileron hinge 
bolt installations and take any corrective actions before further 
flight by following the Accomplishment Instructions-Part 1-On 
Aircraft-Inspection in Pilatus SB 55-005.
    (2) For Group 1 airplanes: Within 100 hours time-in-service 
(TIS) after the inspection required by paragraph (h)(1) of this AD 
and thereafter at intervals not to exceed 100 hours TIS until the 
modification required by paragraph (i) of this AD is done, inspect 
the elevator, rudder, and RH aileron hinge bolt installations and 
take any corrective actions before further flight by following the 
Accomplishment Instructions-Part 2-On Aircraft-CONFIG 1-Repeat 
Inspections in Pilatus SB 55-005.

(i) Modify Group 1 Airplanes

    Within 11 months after the effective date of this AD, modify the 
hinge bolt installations on the elevator, rudder, and RH aileron 
assemblies by following the Accomplishment Instructions-Part 3-On 
Aircraft-Modification from CONFIG 1 to CONFIG 2 in Pilatus SB 55-
005. Modifying the elevator, rudder, and RH aileron hinge bolt 
installations terminates the repetitive inspections required by 
paragraph (h)(2) of this AD.

(j) Installation Prohibition

    As of the following applicable compliance time, do not install 
on any airplane an elevator assembly part number (P/N) 
113.50.06.011, 113.50.06.012, 6305.0010.00, 6305.0010.52, 
6305.0010.53, 6305.0010.54, or 6305.0010.55, or a rudder assembly P/
N 113.40.06.018, 6302.0010.51, or 6302.0010.52.
    (1) For Group 1 airplanes: As of the modification required by 
paragraph (i) of this AD.
    (2) For Group 2 airplanes: As of the effective date of this AD.

(k) Alternative Methods of Compliance (AMOCs)

    (1) 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. In accordance with 14 CFR 39.19, 
send your request to your principal inspector or local Flight 
Standards District Office, as appropriate. If sending information 
directly to the manager of the certification office, send it to the 
attention of the person identified in Related Information or email: 
[email protected].
    (2) Before using any approved AMOC, notify your appropriate 
principal inspector, or lacking a principal inspector, the manager 
of the local flight standards district office/certificate holding 
district office.

(l) Related Information

    (1) For more information about this AD, contact Doug Rudolph, 
Aviation Safety Engineer, FAA, General Aviation & Rotorcraft

[[Page 51838]]

Section, International Validation Branch, 901 Locust, Room 301, 
Kansas City, MO 64106; phone: (816) 329-4059; fax: (816) 329-4090; 
email: [email protected].
    (2) Refer to European Union Aviation Safety Agency (EASA) AD 
2021-0098, dated April 9, 2021, for more information. You may 
examine the EASA AD in the AD docket at https://www.regulations.gov 
by searching for and locating it in Docket No. FAA-2021-0786.
    (3) For service information identified in this AD, contact 
Pilatus Aircraft Ltd., Customer Support General Aviation, CH-6371 
Stans, Switzerland; phone: +41 848 24 7 365; email: 
aircraft.com">techsupport.ch@pilatus-aircraft.com; website: https://www.pilatus-
aircraft.com. 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.

    Issued on September 9, 2021.
Lance T. Gant,
Director, Compliance & Airworthiness Division, Aircraft Certification 
Service.
[FR Doc. 2021-19961 Filed 9-16-21; 8:45 am]
BILLING CODE 4910-13-P