[Federal Register Volume 86, Number 57 (Friday, March 26, 2021)]
[Proposed Rules]
[Pages 16124-16126]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2021-05944]



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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2020-1074; Project Identifier MCAI-2020-01257-A]
RIN 2120-AA64


Airworthiness Directives; Pilatus Aircraft Ltd. Airplanes

AGENCY: Federal Aviation Administration (FAA), DOT.

ACTION: Notice of proposed rulemaking (NPRM).

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SUMMARY: The FAA proposes to adopt a new airworthiness directive (AD) 
for certain Pilatus Aircraft Ltd. (Pilatus) Model PC-24 airplanes. This 
proposed 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 the engine attachment hardware 
not conforming to the approved design, which could affect the 
structural integrity of the airplane. This proposed AD would require 
inspecting the engine attachment hardware for missing washers and loose 
nuts and taking corrective actions as necessary. 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 May 10, 
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., 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. It is also available at 
https://www.regulations.gov by searching for and locating Docket No. 
FAA-2020-1074.

Examining the AD Docket

    You may examine the AD docket at https://www.regulations.gov by 
searching for and locating Docket No. FAA-2020-1074; 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, 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 proposal. Send your comments to an address listed 
under ADDRESSES. Include ``Docket No. FAA-2020-1074; Project Identifier 
MCAI-2020-01257-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 
this 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 NPRM. 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 European Union Aviation Safety Agency (EASA), which is the 
Technical Agent for the Member States of the European Union, has issued 
EASA AD 2020-0194, dated September 8, 2020 (referred to after this as 
``the MCAI''), to address an unsafe condition on certain serial-
numbered Pilatus Model PC-24 airplanes. The MCAI states:

    During a scheduled maintenance inspection, the engine attachment 
hardware of a PC-24 airplane was found not to conform to the 
approved design. A washer was missing beneath each of the four 
mating bolt heads on the rear engine beam. In addition, some of the 
keeper fitting attachment bolts on the LH/RH middle inner nacelle 
were found with loose nuts. It was also determined that other 
aeroplanes may have the same non-conformities.
    This condition, if not detected and corrected, could damage the 
engine attachment hardware, possibly affecting the structural 
integrity of the aeroplane.
    To address this potential unsafe condition, Pilatus issued the 
[service bulletin] SB, providing instructions for inspection and 
corrective action.
    For the reason described above, this [EASA] AD requires a one-
time inspection for missing washers and loose nuts on the engine 
attachment hardware and, depending on findings, the accomplishment 
of applicable corrective action(s).

    You may obtain further information by examining the MCAI in the AD 
docket at https://www.regulations.gov by searching for and locating 
Docket No. FAA-2020-1074.

Related Service Information Under 1 CFR Part 51

    The FAA reviewed Pilatus PC-24 Service Bulletin No. 71-001, dated 
June 30, 2020. This service information specifies procedures for 
inspecting the engine attachment hardware for loose nuts and missing 
washers and taking corrective actions depending on findings. This 
service information is reasonably available because the interested 
parties have access to it through their normal course of business

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or by the means identified in ADDRESSES.

FAA's Determination and Requirements of the Proposed AD

    This product has been approved by the aviation authority of another 
country and is approved for operation in the United States. Pursuant to 
our 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 the unsafe condition described previously is likely 
to exist or develop on other products of the same type design.

Costs of Compliance

    The FAA estimates that this AD, if adopted as proposed, would 
affect 34 airplanes of U.S. registry.
    The FAA estimates that it would take 2.5 work-hours to do the one-
time inspections. The average labor rate is $85 per work-hour.
    Based on these figures, the FAA estimates the cost of the proposed 
AD on U.S. operators would be $7,225 or $212.50 per airplane.
    The FAA also estimates that, as on-condition costs, installing 
missing washers, replacing bolts, and doing an eddy current inspection 
of the bolt holes would take 4.5 work-hours and require parts costing 
$200 for a cost of $582.50 per airplane. This estimate assumes 
replacing all of the rear engine beam attachment bolts and washers and 
doing an eddy current inspection of all the attachment bolt holes. If 
the bolt holes are found damaged during the eddy current inspection, 
the damage will vary considerably from airplane to airplane, and the 
FAA has no way of estimating a repair cost. In addition, the FAA has no 
way of determining the number of aircraft that might need these 
actions.
    The FAA has included all known costs in this cost estimate. 
According to the manufacturer, however, some of the costs of this AD 
may be covered under warranty, thereby reducing the cost impact on 
affected operators.

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) 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]

    2. The FAA amends Sec.  39.13 by adding the following new 
airworthiness directive:

Pilatus Aircraft Ltd.: Docket No. FAA-2020-1074; Project Identifier 
MCAI-2020-01257-A.

(a) Comments Due Date

    The FAA must receive comments on this airworthiness directive 
(AD) by May 10, 2021.

(b) Affected ADs

    None.

(c) Applicability

    This AD applies to Pilatus Aircraft Ltd. Model PC-24 airplanes, 
serial numbers (S/Ns) 101 through 162, S/N 164, S/N 165, S/N 167, 
and S/N 168, certificated in any category.

(d) Subject

    Joint Aircraft System Component (JASC) Code 7120, Engine Mount 
Section.

(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 identifies the unsafe condition as engine 
attachment hardware not conforming to the approved design. The FAA 
is issuing this AD to detect and address incorrectly installed 
attachment hardware in the engine and nacelle area. The unsafe 
condition, if not addressed, could result in damage to the engine 
attachment hardware, which may affect the structural integrity of 
the airplane.

(f) Actions and Compliance

    Unless already done, do the actions in paragraphs (f)(1) and (2) 
of this AD at the next annual inspection after the effective date of 
this AD or within 11 months after the effective date of this AD, 
whichever occurs later.
    (1) Inspect the left hand (LH) and right hand (RH) middle inner 
nacelles for loose nuts and correctly install any loose nut before 
further flight by following section 3.B(1) of the Accomplishment 
Instructions in Pilatus PC-24 Service Bulletin No. 71-001, dated 
June 30, 2020 (Pilatus SB 71-001).
    (2) Inspect the LH and RH front and rear engine beams for 
missing washers by following section 3.B(2)(a) through (b) of the 
Accomplishment Instructions in Pilatus SB 71-001. If there are any 
missing washers, before further flight, do an eddy current 
inspection of the bolt holes for damage by following section 3.C of 
the Accomplishment Instructions in Pilatus SB 71-001. Where Pilatus 
SB 71-001 specifies obtaining repair instructions from Pilatus, the 
instructions must be accomplished using a method approved by the 
Manager, International Validation Branch, FAA; or the European Union 
Aviation Safety Agency (EASA); or Pilatus's EASA Design Organization 
Approval (DOA). If approved by the DOA, the approval must include 
the DOA-authorized signature.

(g) 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. If sending information directly to 
the manager of the International Validation Branch, send it to the 
attention of the person identified in Related Information.
    (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.

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(h) Related Information

    (1) 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; phone: (816) 329-4059; fax: (816) 329-4090; 
email: [email protected].
    (2) Refer to MCAI EASA AD 2020-0194, dated September 8, 2020, 
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-2020-1074.
    (3) For service information identified in this AD, contact 
Pilatus Aircraft Ltd., CH-6371, Stans, Switzerland; phone: +41 848 
24 7 365; email: aircraft.com">techsupport.ch@pilatus-aircraft.com; website: 
http://www.pilatus-aircraft.com/. You may review 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 March 17, 2021.
Lance T. Gant,
Director, Compliance & Airworthiness Division, Aircraft Certification 
Service.
[FR Doc. 2021-05944 Filed 3-25-21; 8:45 am]
BILLING CODE 4910-13-P