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[Federal Register Volume 86, Number 34 (Tuesday, February 23, 2021)]
[Rules and Regulations]
[Pages 10744-10747]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2021-03476]

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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2020-0813; Product Identifier 2019-CE-040-AD; Amendment 
39-21387; AD 2021-02-04]
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 
Pilatus Aircraft Ltd. (Pilatus) Model PC-12/47E airplanes. 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

[[Page 10745]]

inboard flap fairings aft (IFFAs) having an incorrect shape, which may 
result in chafing between the IFFA and the associated front inboard 
tension rod. This AD requires an inspection of the IFFAs for the 
correct shape and chafing between the IFFA and the associated front 
inboard tension rod, with corrective action as necessary. This 
condition could lead to failure of the inboard flap drive arm with 
consequent asymmetric flap extension, resulting in reduced control of 
the airplane. The FAA is issuing this AD to address the unsafe 
condition on these products.

DATES: This AD is effective March 30, 2021.
    The Director of the Federal Register approved the incorporation by 
reference of a certain publication listed in this AD as of March 30, 
2021.

ADDRESSES: For service information identified in this final rule, 
contact Pilatus Aircraft, Ltd., Customer Support PC-12, CH-6371 Stans, 
Switzerland; phone: +41 41 619 33 33; fax: +41 41 619 73 11; email: 
aircraft.com">supportPC12@pilatus-aircraft.com; website: https://www.pilatus-
aircraft.com. You may review this referenced service information at the 
FAA, Airworthiness Products Section, Operational Safety Branch, 901 
Locust, Kansas City, Missouri 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-2020-0813.

Examining the AD Docket

    You may examine the AD docket at https://www.regulations.gov by 
searching for and locating Docket No. FAA-2020-0813; 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 
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, Aviation Safety 
Engineer, General Aviation & Rotorcraft Section, International 
Validation Branch, FAA, 901 Locust, Room 301, Kansas City, Missouri 
64106; phone: (816) 329-4059; fax: (816) 329-4090; email: 
[email protected].

SUPPLEMENTARY INFORMATION:

Background

    The FAA issued a notice of proposed rulemaking (NPRM) to amend 14 
CFR part 39 by adding an AD that would apply to all Pilatus Model PC-
12/47E airplanes. The NPRM published in the Federal Register on 
September 16, 2020 (85 FR 57804). In the NPRM, the FAA proposed to 
require an inspection of the IFFAs for the correct shape and chafing 
between the IFFA and the associated front inboard tension rod, with 
corrective action as necessary.
    The NPRM was based on MCAI from the European Union Aviation Safety 
Agency (EASA), which is the Technical Agent for the Member States of 
the European Union. EASA issued AD No.: 2019-0231, dated September 13, 
2019 (referred to after this as ``the MCAI''), to correct an unsafe 
condition for Pilatus Model PC-12/47E airplanes. The MCAI states:

    On the final assembly line of PC-12/47E aeroplanes, IFFAs were 
detected having an incorrect shape. As a consequence, chafing 
between the IFFA and the associated front inboard tension rod could 
occur, may cause corrosion of the bare rod aluminium tube and reduce 
aluminium thickness.
    This condition, if not detected and corrected, could lead to 
failure of the inboard flap drive arm with consequent asymmetric 
flap extension, possibly resulting in reduced control of the 
aeroplane.
    To address this potential unsafe condition, Pilatus issued the 
[service bulletin] SB to provide inspection and modification 
instructions.
    For the reason described above, this [EASA] AD requires a one-
time inspection of both IFFA and, depending on findings, a follow-on 
inspection of the associated front inboard tension rod for chafing, 
and modification or replacement of affected parts.

    You may examine the MCAI at https://www.regulations.gov by 
searching for and locating Docket No. FAA-2020-0813.

Discussion of Final Airworthiness Directive

Comments

    The FAA received two comments from Pilatus. The following presents 
the comments received on the NPRM and the FAA's response to each 
comment.
    Pilatus requested the FAA reduce the applicability of the proposed 
AD from all Model PC-12/47E airplanes to Model PC-12/47E airplanes with 
serial number (S/N) 1576 and higher. Pilatus stated that due to an 
engineering change in 2014, the left-hand (LH) IFFA, part number (P/N) 
557.52.12.223, and the right-hand (RH) IFFA, P/N 557.52.12.224, 
introduced on airplanes with S/N 1576 and higher, have different 
attachment hole positions and a maximum hole position difference of 
more than 12mm. As a result, it is not physically possible to install 
P/Ns 557.52.12.223 and 557.52.12.224 on airplanes with an S/N lower 
than 1576.
    The FAA partially agrees. The commenter is correct that the 
affected IFFAs cannot be installed on Model PC-12/47E airplanes with an 
S/N lower than 1576. The FAA has revised paragraph (f) of this AD to 
limit the inspection of the IFFAs to airplanes with an S/N 1576 and 
higher.
    Pilatus acknowledged that tension rod P/N 527.52.12.135 can be 
installed on all Model PC-12/47E airplanes but requested the FAA limit 
the tension rod inspection for airplanes with an S/N lower than 1576 to 
only those with maintenance records showing that the tension rod had 
been installed.
    The FAA partially agrees. The FAA has revised the tension rod 
inspection to limit its scope for airplanes with an S/N lower than 
1576. Because the tension rods are not life-limited parts, there is no 
regulatory requirement for them to be serialized or for operators to 
record or retain information about the part's traceability. Therefore, 
operators would be unable to comply with, and the FAA would be unable 
to enforce, the change requested by the commenter, as maintenance 
records may not identify if a tension rod was removed from an airplane 
with an S/N 1576 or higher. Instead, the FAA has changed the AD so that 
the inspection of the tension rod is required for all airplanes with a 
S/N 1576 or higher and for airplanes with a S/N 1001 through 1575 if 
tension rod P/N 527.52.12.135 is installed.

Conclusion

    The FAA reviewed the relevant data, considered any comments 
received, and determined that air safety requires adopting this AD as 
proposed. Accordingly, the FAA is issuing this AD to address the unsafe 
condition on these products. Except for the changes described 
previously, this AD is adopted as proposed in the NPRM. None of the 
changes will increase the economic burden on any operator.

Related Service Information Under 1 CFR Part 51

    The FAA reviewed Pilatus PC-12 Service Bulletin No: 27-026, dated 
July 10, 2019 (Pilatus SB No. 27-026). The service information 
specifies procedures for inspecting and correcting chafing between the 
left and right IFFAs and the associated front inboard tension rods. 
This service information is reasonably available because the interested 
parties have access to it through their normal

[[Page 10746]]

course of business or by the means identified in ADDRESSES.

Differences Between This AD and the MCAI

    The MCAI only requires inspection of the tension rods if the IFFAs 
are modified because they have been found to have the incorrect shape. 
Due to the length of time between manufacture and the issuance of this 
AD, operators could have installed an affected tension rod onto an 
airplane that was not manufactured with the defective part. Therefore, 
this AD requires inspection for chafing damage on the tension rods on 
all Model PC-12/47E airplanes that have an affected tension rod 
installed.

Costs of Compliance

    The FAA estimates that this AD will affect 18 products of U.S. 
registry. The FAA also estimates that it will take about 2.5 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 $1,600 
per product.
    Based on these figures, the FAA estimates the cost of this AD on 
U.S. operators will be $32,634 or $1,813 per product.
    The FAA has included all costs in this cost estimate. According to 
the manufacturer, however, all or 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

    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 
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 Amendment

    Accordingly, under the authority delegated to me by the 
Administrator, the FAA amends 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 adding the following new airworthiness 
directive:

2021-02-04 Pilatus Aircraft Ltd.: Amendment 39-21387; Docket No. 
FAA-2020-0813; Product Identifier 2019-CE-040-AD.

(a) Effective Date

    This airworthiness directive (AD) is effective March 30, 2021.

(b) Affected ADs

    None.

(c) Applicability

    This AD applies to Pilatus Aircraft Ltd. Model PC-12/47E 
airplanes, all serial numbers (S/Ns), certificated in any category.

(d) Subject

    Joint Aircraft System Component (JASC) Code 2700: Flight 
Controls.

(e) Reason

    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 inboard flap 
fairings aft (IFFAs) having an incorrect shape. The FAA is issuing 
this AD to prevent chafing between the IFFA and the front inboard 
tension rod, and consequent corrosion of the bare rod aluminum tube 
and reduced aluminum thickness. This condition, if not corrected, 
could lead to failure of the inboard flap drive arm, asymmetric flap 
extension, and reduced control of the airplane.

(f) Actions and Compliance

    (1) For airplanes with a S/N 1576 and higher, unless already 
done, within 100 hours time-in-service (TIS) after the effective 
date of this AD or within 6 months after the effective date of this 
AD, whichever occurs first, inspect the left-hand (LH) and right-
hand (RH) IFFAs for correct shape and clearance with the LH and RH 
tension rods by following step 3.B.(1) and Figures 2 and 3 of the 
Accomplishment Instructions--Aircraft in Pilatus PC-12 Service 
Bulletin No: 27-026, dated July 10, 2019 (Pilatus SB 27-026).
    (i) If the shape of the LH or RH IFFA is incorrect or if the 
clearance between the IFFA and the tension rod is less than 5 mm 
(0.2 inch), before further flight, modify the IFFA and inspect the 
tension rods for chafing by following section 3.C. of the 
Accomplishment Instructions--Aircraft in Pilatus SB 27-026.
    (ii) If the shape of the LH and RH IFFAs is correct and the 
clearance between the IFFA and the tension rod is at least 5 mm (0.2 
inch), before further flight, inspect the front inboard LH and RH 
tension rods for chafing by following step 3.C.(12)(a) of the 
Accomplishment Instructions--Aircraft in Pilatus SB 27-026. If the 
LH or RH tension rod has any chafing, before further flight, replace 
the tension rod by following step 3.C.(12)(b) of the Accomplishment 
Instructions--Aircraft in Pilatus SB 27-026.
    (2) For airplanes with a S/N 1001 through S/N 1575, inclusive, 
that have a tension rod part number (P/N) 527.52.12.135 installed, 
unless already done, within 100 hours TIS after the effective date 
of this AD or within 6 months after the effective date of this AD, 
whichever occurs first, inspect the front inboard LH and RH tension 
rods for chafing by following step 3.C.(12)(a) of the Accomplishment 
Instructions--Aircraft in Pilatus SB 27-026. If the LH or RH tension 
rod has any chafing, before further flight, replace the tension rod 
by following step 3.C.(12)(b) of the Accomplishment Instructions--
Aircraft in Pilatus SB 27-026.
    (3) For all Model PC-12/47E airplanes, as of the effective date 
of this AD, do not install on any airplane an LH IFFA P/N 
557.52.12.223, RH IFFA P/N 557.52.12.224, or tension rod P/N 
527.52.12.135 unless the part has been inspected and all corrective 
actions have been taken as required by this AD.

(g) Alternative Methods of Compliance (AMOCs)

[[Page 10747]]

    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 information to Doug Rudolph, 
Aviation Safety Engineer, General Aviation & Rotorcraft Section, 
International Validation Branch, FAA, 901 Locust, Room 301, Kansas 
City, Missouri 64106; phone: (816) 329-4059; fax: (816) 329-4090; 
email: [email protected]. Before using any approved AMOC on any 
airplane to which the AMOC applies, notify your appropriate 
principal inspector (PI) in the FAA Flight Standards District Office 
(FSDO), or lacking a PI, your local FSDO.

(h) Related Information

    (1) Refer to MCAI European Union Aviation Safety Agency AD No. 
2019-0231, dated September 13, 2019, for related information. You 
may examine the MCAI at https://www.regulations.gov by searching for 
and locating Docket No. FAA-2020-0813.
    (2) For service information related to this AD, contact Pilatus 
Aircraft, Ltd., Customer Support PC-12, CH-6371 Stans, Switzerland; 
phone: +41 41 619 33 33; fax: +41 41 619 73 11; email: 
aircraft.com">supportPC12@pilatus-aircraft.com; website: https://www.pilatus-
aircraft.com. You may review this referenced service information at 
the FAA, Airworthiness Products Section, Operational Safety Branch, 
901 Locust, Kansas City, Missouri 64106. For information on the 
availability of this material at the FAA, call (816) 329-4148.

(i) Material Incorporated by Reference

    (1) The Director of the Federal Register approved the 
incorporation by reference of the service information listed in this 
paragraph under 5 U.S.C. 552(a) and 1 CFR part 51.
    (2) You must use this service information as applicable to do 
the actions required by this AD, unless the AD specifies otherwise.
    (i) Pilatus Service Bulletin No: 27-026, dated July 10, 2019.
    (ii) [Reserved]
    (3) For Pilatus Aircraft Ltd. service information identified in 
this AD, contact Pilatus Aircraft, Ltd., Customer Support PC-12, CH-
6371 Stans, Switzerland; phone: +41 41 619 33 33; fax: +41 41 619 73 
11; email: aircraft.com">supportPC12@pilatus-aircraft.com; website: https://
www.pilatus-aircraft.com.
    (4) You may view this service information at FAA, Airworthiness 
Products Section, Operational Safety Branch, 901 Locust, Kansas 
City, Missouri 64106. For information on the availability of this 
material at the FAA, call (816) 329-4148.
    (5) You may view this service information that is incorporated 
by reference at the National Archives and Records Administration 
(NARA). For information on the availability of this material at 
NARA, email: [email protected], or go to: https://www.archives.gov/federal-register/cfr/ibr-locations.html.

    Issued on January 6, 2021.
Lance T. Gant,
Director, Compliance & Airworthiness Division, Aircraft Certification 
Service.
[FR Doc. 2021-03476 Filed 2-22-21; 8:45 am]
BILLING CODE 4910-13-P
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