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Airworthiness Directive packet

AD 2023-09-12

Airworthiness Directives; Pilatus Aircraft Ltd. Airplanes

1 · Quick read — prepared by AircraftDirectives

Our plain-language summary — not the regulation

Requires inspecting the power return and chassis grounding cable attachment points at frame 37, including the attachment parts, and depending on the inspection results, corrective action.

AD number
2023-09-12
Federal Register document
2023-11447
Citation
88 FR 34745
Amendment
39-22435
Docket
Docket No. FAA-2023-0421
Action
Final rule.
Published
2023-05-31
Effective
2023-07-05
Effective (as stated in the rule)
This AD is effective July 5, 2023.
Issued by
Transportation Department, Federal Aviation Administration
Regulation
14 CFR 39
Applies to (in our index)
Pilatus PC-12

2 · Official Federal Register document — government source, verbatim

Reproduced unedited from the Federal Register
[Federal Register Volume 88, Number 104 (Wednesday, May 31, 2023)]
[Rules and Regulations]
[Pages 34745-34747]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2023-11447]


========================================================================
Rules and Regulations
                                                Federal Register
________________________________________________________________________

This section of the FEDERAL REGISTER contains regulatory documents 
having general applicability and legal effect, most of which are keyed 
to and codified in the Code of Federal Regulations, which is published 
under 50 titles pursuant to 44 U.S.C. 1510.

The Code of Federal Regulations is sold by the Superintendent of Documents. 

========================================================================


Federal Register / Vol. 88, No. 104 / Wednesday, May 31, 2023 / Rules 
and Regulations

[[Page 34745]]


DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2023-0421; Project Identifier MCAI-2022-01360-A; 
Amendment 39-22435; AD 2023-09-12]
RIN 2120-AA64


Airworthiness Directives; Pilatus Aircraft Ltd. Airplanes

AGENCY: Federal Aviation Administration (FAA), DOT.

ACTION: Final rule.

-----------------------------------------------------------------------

SUMMARY: The FAA is adopting a new airworthiness directive (AD) for 
certain Pilatus Aircraft Ltd. (Pilatus) Model PC-12, PC-12/45, PC-12/
47, and PC-12/47E airplanes. This AD is 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 insufficient grounding of the vapor cycle cooling system 
(VCCS) compressor/condenser. This AD requires inspecting the power 
return and chassis grounding cable attachment points at frame 37, 
including the attachment parts, and depending on the inspection 
results, corrective action. This AD also requires modifying the 
installation of the VCCS compressor/condenser power return cables and 
installing an additional isolated VCCS chassis ground cable. The FAA is 
issuing this AD to address the unsafe condition on these products.

DATES: This AD is effective July 5, 2023.
    The Director of the Federal Register approved the incorporation by 
reference of a certain publication listed in this AD as of July 5, 
2023.

ADDRESSES: 
    AD Docket: You may examine the AD docket at regulations.gov under 
Docket No. FAA-2023-0421; 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.
    Material Incorporated by Reference:
     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: 
aircraft.com">techsupport.ch@pilatus-aircraft.com; website: 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 (817) 222-5110. It is also available at 
regulations.gov under Docket No. FAA-2023-0421.

FOR FURTHER INFORMATION CONTACT: Doug Rudolph, Aviation Safety 
Engineer, International Validation Branch, FAA, 1600 Stewart Avenue, 
Suite 410, Westbury, NY 11590; phone: (816) 329-4059; 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 certain serial-numbered 
Pilatus Model PC-12, PC-12/45, PC-12/47, and PC-12/47E airplanes. The 
NPRM published in the Federal Register on February 27, 2023 (88 FR 
12273). The NPRM was prompted by AD 2022-0212, dated October 18, 2022 
(referred to after this as ``the MCAI''), issued by the European Union 
Aviation Safety Agency (EASA), which is the Technical Agent for the 
Member States of the European Union.
    The MCAI was prompted by a reported occurrence of a burning odor 
coming from the air conditioning vents during the climb phase of a 
Pilatus Model PC-12/47E airplane. An investigation identified that 
insufficient grounding of the VCCS compressor/condenser at frame 37 
resulted in severe heat damage to the baseplate and adjacent metal 
support structure. It was determined that this condition may occur on 
airplanes equipped in production with the large oxygen bottle installed 
on the right-hand side of the rear fuselage. To address the unsafe 
condition, the MCAI requires a one-time inspection of the power return 
and chassis grounding cable attachment point at frame 37, including the 
attachment parts, and modification of the installation of the VCCS.
    In the NPRM, the FAA proposed to require a one-time inspection of 
the power return and chassis grounding cable attachment point at frame 
37, including the attachment parts, and modification of the 
installation of the VCCS. This condition, if not addressed, could, in 
the case of damage to the oxygen supply line, lead to an uncontrolled 
fire with damage to the airplane and injury to the occupants. The FAA 
is issuing this AD to address the unsafe condition on these products.
    You may examine the MCAI in the AD docket at regulations.gov under 
Docket No. FAA-2023-0421.

Discussion of Final Airworthiness Directive

Comments

    The FAA received a comment from the Air Line Pilots Association, 
International (ALPA), who supported the NPRM without change. In 
addition, an individual commenter submitted a comment to the docket, 
but did not comment on the proposed required actions or the 
determination of the costs in the NPRM.

Conclusion

    These products have been approved by the aviation authority of 
another country and are 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 referenced above. The FAA reviewed the relevant data, 
considered the comment 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 
minor editorial changes, this AD is adopted as proposed in the NPRM.

[[Page 34746]]

Related Service Information Under 1 CFR Part 51

    The FAA reviewed Pilatus PC-12 Service Bulletin 21-016, dated 
August 15, 2022, which specifies procedures for inspecting the power 
return and chassis grounding cable attachment point on the airframe at 
frame 37, including the attachment parts, modifying the installation of 
the VCCS compressor/condenser power return cables, and installing an 
additional isolated VCCS chassis ground cable. This service bulletin 
also specifies contacting Pilatus if any damage is found.
    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 ADDRESSES.

Differences Between This AD and the MCAI

    The MCAI requires contacting the manufacturer for approved 
corrective action instructions if any discrepancy is found during the 
inspection. This AD requires contacting either the Manager, 
International Validation Branch, FAA; EASA; or Pilatus's EASA Design 
Organization Approval (DOA). If approved by the DOA, the approval must 
include the DOA-authorized signature.

Costs of Compliance

    The FAA estimates that this AD affects 8 airplanes of U.S. 
registry.
    The FAA estimates the following costs to comply with this AD:

                                                 Estimated Costs
----------------------------------------------------------------------------------------------------------------
                                                                                     Cost per      Cost on U.S.
            Action                        Labor cost               Parts cost         product        operators
----------------------------------------------------------------------------------------------------------------
Inspect......................  3 work-hours x $85 per hour =    Not Applicable..            $255          $2,040
                                $255.
Modify.......................  5 work-hours x $85 per hour =    $667............           1,092           8,736
                                $425.
----------------------------------------------------------------------------------------------------------------

    The repair instructions that may be needed as a result of the 
inspection could vary significantly from airplane to airplane. The FAA 
has no data to determine the costs to accomplish the repair or the 
number of airplanes that would need this repair.

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:

2023-09-12 Pilatus Aircraft Ltd.: Amendment 39-22435; Docket No. 
FAA-2023-0421; Project Identifier MCAI-2022-01360-A.

(a) Effective Date

    This airworthiness directive (AD) is effective July 5, 2023.

(b) Affected ADs

    None.

(c) Applicability

    This AD applies to Pilatus Aircraft Ltd. Model PC-12, PC-12/45, 
PC-12/47, and PC-12/47E airplanes, serial numbers 466, 467, 725, 
861, 1032, 1052, 1082, 1115, 1232, 1411, 1428, 1439, 1530, 1541, 
1663, 1725, and 1802, certificated in any category.

(d) Subject

    Joint Aircraft System Component (JASC) Code 2197, Air 
Conditioning System Wiring.

(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 insufficient 
grounding of the vapor cycle cooling system (VCCS) compressor/
condenser. The FAA is issuing this AD to address this condition. The 
unsafe condition, if not addressed, could, in the case of damage to 
the oxygen supply line, lead to an uncontrolled fire with damage to 
the airplane, and injury to the occupants.

(f) Compliance

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

(g) Required Actions

    (1) Within 2 months after the effective date of this AD, inspect 
the power return and chassis grounding cable attachment points at 
frame 37, including the attachment parts, for physical and heat 
damage, de-lamination, and corrosion in accordance with steps (2) 
through (6) of Section 3.B. of the Accomplishment Instructions in 
Pilatus PC-12 Service Bulletin 21-016, dated August 15, 2022 
(Pilatus PC-12 SB 21-016).
    (2) If, during the inspection required by paragraph (g)(1) of 
this AD, any physical or heat damage, de-lamination, or corrosion as 
identified in steps (2) through (6) of Section 3.B. of the 
Accomplishment Instructions in Pilatus PC-12 SB 21-016 is detected, 
before further flight, repair using a method approved by the 
Manager, International Validation Branch, FAA; the European Union 
Aviation Safety Agency (EASA); or Pilatus's

[[Page 34747]]

EASA Design Organization Approval (DOA). If approved by the DOA, the 
approval must include the DOA-authorized signature.
    (3) Within 2 months after the effective date of this AD, modify 
the installation of the VCCS compressor/condenser power return 
cables and install an additional isolated VCCS chassis ground cable 
in accordance with Section 3.C. of the Accomplishment Instructions 
in Pilatus PC-12 SB 21-016. Where the service bulletin specifies 
discarding the stop angle, this AD requires removing the stop angle 
from service.

(h) 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 Sec.  39.19. In accordance with Sec.  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 International Validation Branch, mail 
it to the address identified in paragraph (i)(2) of this AD or email 
to: [email protected]. If mailing information, also submit 
information by email. 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.

(i) Additional Information

    (1) Refer to EASA AD 2022-0212, dated October 18, 2022, for 
related information. This EASA AD may be found in the AD docket at 
regulations.gov under Docket No. FAA-2023-0421.
    (2) For more information about this AD, contact Doug Rudolph, 
Aviation Safety Engineer, International Validation Branch, FAA, 1600 
Stewart Avenue, Suite 410, Westbury, NY 11590; phone: (816) 329-
4059; email: [email protected].

(j) 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 PC-12 Service Bulletin 21-016, dated August 15, 
2022.
    (ii) [Reserved]
    (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: pilatus-aircraft.com.
    (4) 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 (817) 222-5110.
    (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: www.archives.gov/federal-register/cfr/ibr-locations.html.

    Issued on May 9, 2023.
Michael Linegang,
Acting Director, Compliance & Airworthiness Division, Aircraft 
Certification Service.
[FR Doc. 2023-11447 Filed 5-30-23; 8:45 am]
BILLING CODE 4910-13-P

Sources. Section 1 is written by AircraftDirectives from the record below and is a reading aid only. Section 2 is the United States Government's own text, reproduced without edit.

Federal Register: https://www.federalregister.gov/documents/2023/05/31/2023-11447/airworthiness-directives-pilatus-aircraft-ltd-airplanes

Official PDF: https://www.govinfo.gov/content/pkg/FR-2023-05-31/pdf/2023-11447.pdf

FAA DRS record: https://drs.faa.gov/browse/excelExternalWindow/FR-ADFRAWD-2023-11447-0000000000.0001

Packet generated 2026-08-18 08:18 UTC.

This packet is not an airworthiness determination and not legal or maintenance advice. AircraftDirectives reproduces official records and condenses their wording for easier reading. It does not decide, certify or imply whether any aircraft, engine, appliance or part is airworthy, compliant, affected by this directive, or eligible for return to service. No inspection, approval, or determination of any kind is performed or implied by this document.

Section 1 is a reading aid, not the rule. It is our own plain-language condensation, written to help a reader find the relevant directive quickly. It is NOT a substitute for the regulation, it may omit conditions, exceptions, compliance times, alternative methods of compliance (AMOCs) and applicability limits, and it has no legal force whatsoever. Only the official text governs. Where Section 1 and Section 2 differ in any respect, Section 2 - and the official source it was retrieved from - controls absolutely.

Responsibility remains with the owner/operator. Under 14 CFR §91.403 and §91.417 the owner or operator is responsible for maintaining airworthiness and for required records; under §39.7 no person may operate a product to which an airworthiness directive applies except in accordance with that directive. Determining applicability to a specific serial number and configuration, and performing or supervising any required action, is the responsibility of the owner/operator and appropriately certificated personnel.

Accuracy and currency. Section 2 was retrieved at the time stamped above and is reproduced without edit; Federal Register material is a work of the United States Government. Directives are amended, corrected and superseded over time, and this sheet is a snapshot, not a live record - it does not update after printing. Re-check the official sources before acting on it. This packet is provided without warranty of any kind, express or implied, including fitness for a particular purpose. We do not sell parts and have no commercial interest in any action a directive may require.

AircraftDirectives · AD 2023-09-12 · Section 1 is our plain-language reading aid; Section 2 is the official Federal Register text and controls where the two differ. Not an airworthiness determination — 14 CFR §91.403 / §91.417 responsibility remains with the owner/operator. Retrieved 2026-08-18 08:18 UTC.