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[Federal Register Volume 90, Number 19 (Thursday, January 30, 2025)]
[Proposed Rules]
[Pages 8507-8510]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2025-01968]

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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2025-0013; Project Identifier MCAI-2024-00375-A]
RIN 2120-AA64

Airworthiness Directives; Piaggio Aviation S.p.A. Airplanes

AGENCY: Federal Aviation Administration (FAA), DOT.

ACTION: Notice of proposed rulemaking (NPRM).

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SUMMARY: The FAA proposes to supersede Airworthiness Directive (AD) 
2023-25-03, which applies to certain Piaggio Aviation S.p.A. (Piaggio) 
Model P-180 airplanes. AD 2023-25-03 requires a one-time detailed 
inspection of the horizontal stabilizer (HS) central box for corrosion; 
an assessment of the corrosion level; and depending on the 
determination, repetitive detailed inspections of the HS central box 
for corrosion and the internal composite structure for surface cracks, 
distortion, and damage; and repair or replacement of the HS assembly. 
Repair or replacement of the HS assembly is terminating action for the 
repetitive inspections. Since the FAA issued AD 2023-25-03, it was 
determined that AD 2023-25-03 imposed an unintended restriction that is 
not in the mandatory continuing airworthiness information (MCAI). This 
proposed AD would retain certain actions of AD-2023-25-03 and would 
remove the unintended restriction. The FAA is proposing this AD to 
address the unsafe condition on these products.

DATES: The FAA must receive comments on this NPRM by March 17, 2025.

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 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.
    AD Docket: You may examine the AD docket at regulations.gov under 
Docket No. FAA-2025-0013; 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.
    Material Incorporated by Reference:
     For Piaggio material identified in this proposed AD, 
contact Piaggio Aviation S.p.A., P180 Customer Support, via Pionieri e 
Aviatori d'Italia, snc--16154 Genoa, Italy; phone: +39 331 679 74 93; 
email: [email protected].
     You may view this material 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.

FOR FURTHER INFORMATION CONTACT: William McCully, Aviation Safety 
Engineer, FAA, 1600 Stewart Avenue, Suite 410, Westbury, NY 11590; 
phone: (404) 474-5548; 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-2025-0013; Project Identifier 
MCAI-2024-00375-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 
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

[[Page 8508]]

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 William McCully, Aviation Safety Engineer, FAA, 1600 Stewart 
Avenue, Suite 410, Westbury, NY 11590. 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 2023-25-03, Amendment 39-22630 (88 FR 90085, 
December 29, 2023) (AD 2023-25-03), for certain Piaggio Model P-180 
airplanes.
    AD 2023-25-03 was prompted by MCAI originated by the European Union 
Aviation Safety Agency (EASA), which is the Technical Agent for the 
Member States of the European Union. EASA issued EASA AD 2023-0007, 
dated January 13, 2023 (EASA AD 2023-0007, also referred to as the 
MCAI) to correct an unsafe condition identified as a finding of 
corrosion inside the HS central box of a Piaggio Model P-180 airplane 
during scheduled maintenance. A subsequent investigation and inspection 
of 16 other Piaggio Model P-180 airplanes of various configurations and 
ages revealed that corrosion of differing levels of severity was found 
on various aluminum alloy reinforcements in the HS central box of all 
the inspected airplanes. The MCAI also states that this corrosion was 
caused by the formation of a humid environment inside the HS central 
box, from water ingress and/or condensation. Further investigation 
revealed that airplanes left in prolonged inactivity or parked outside 
are more prone to develop corrosion damage.
    AD 2023-25-03 requires a one-time detailed inspection of the HS 
central box for corrosion; an assessment of the corrosion level; and 
depending on the determination, repetitive detailed inspections of the 
HS central box for corrosion and the internal composite structure for 
surface cracks, distortion, and damage; and repair or replacement of 
the HS assembly. Repair or replacement of the HS assembly is 
terminating action for the repetitive inspections. The FAA issued AD 
2023-25-03 to address corrosion on various aluminum alloy 
reinforcements in the HS central box caused by a humid environment 
inside the box from water ingress and/or condensation.

Actions Since AD 2023-25-03 Was Issued

    Since the FAA issued AD 2023-25-03, it was determined that a 
portion of paragraph (g)(4)(ii) of that AD includes an unintended 
requirement to replace the HS assembly after 660 hours time-in-service 
(TIS) or 13 months, whichever occurs first, following a finding of 
level 2 corrosion.
    You may examine the MCAI in the AD docket at regulations.gov under 
Docket No. FAA-2025-0013.

Material Incorporated by Reference Under 1 CFR Part 51

    This proposed AD would require Piaggio Aerospace Service Bulletin 
80-0489, Revision 2, dated November 30, 2022, which the Director of the 
Federal Register approved for incorporation by reference as of February 
2, 2024 (88 FR 90085, December 29, 2023).
    This material 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

    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 and material 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 retains all the actions of AD-2023-05 except for 
the requirement to replace the HS assembly after 660 hours TIS or 13 
months, whichever occurs first, following a finding of level 2 
corrosion. This proposed AD would also require accomplishing the 
actions specified in the material already described except as discussed 
under ``Differences Between this Proposed AD and the MCAI.''

Differences Between This Proposed AD and the MCAI

    The MCAI requires contacting the manufacturer for a determination 
of the corrosion level if any corrosion is found during the initial 
inspection of the HS central box, and if it is determined that level 2 
or 3 corrosion is present, having the manufacturer provide the 
threshold and intervals for doing repetitive inspections of the HS 
central box. This proposed AD would require contacting either the FAA, 
EASA, or Piaggio's EASA Design Organization Approval (DOA). If approved 
by the DOA, the approval must include the DOA-authorized signature.
    Although Piaggio Aerospace Service Bulletin 80-0489, Revision 2, 
dated November 30, 2022, specifies to record the image of the location 
of corroded areas, this proposed AD would not require that action.

Costs of Compliance

    The FAA estimates that this AD, if adopted as proposed, would 
affect 102 airplanes of U.S. registry.
    The FAA estimates the following costs to comply with this proposed 
AD:

                                                 Estimated Costs
----------------------------------------------------------------------------------------------------------------
                                                                                     Cost per      Cost on U.S.
                Action                         Labor cost           Parts cost        product        operators
----------------------------------------------------------------------------------------------------------------
Initial inspection of HS central box    6 work-hours x $85 per                $0            $510         $52,020
 for corrosion.                          hour = $510.
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                                               On-Condition Costs
----------------------------------------------------------------------------------------------------------------
                 Action                           Labor cost            Parts cost         Cost per product
----------------------------------------------------------------------------------------------------------------
Repetitive inspections of HS central box  6 work-hours x $85 per                  $0  $510, per inspection
 for corrosion.                            hour = $510, per                            cycle.
                                           inspection cycle.

[[Page 8509]]

 
Repetitive inspections for surface        6 work-hours x $85 per                  $0  $510, per inspection
 cracks, distortion, and damage.           hour = $510, per                            cycle.
                                           inspection cycle.
Replace HS assembly.....................  10 work-hours x $85 per           $150,000  $150,850.
                                           hour = $850.
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    The repair of the HS assembly that may be required as a result of 
any 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 may require the 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

    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 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 AD 2023-25-03, Amendment 39-22630 
(88 FR 90085, December 29, 2023); and
0
b. Adding the following new airworthiness directive:

Piaggio Aviation S.p.A.: Docket No. FAA-2025-0013; Project 
Identifier MCAI-2024-00375-A.

(a) Comments Due Date

    The FAA must receive comments on this airworthiness directive 
(AD) by March 17, 2025.

(b) Affected ADs

    This AD replaces AD 2023-25-03, Amendment 39-22630 (88 FR 90085, 
December 29, 2023).

(c) Applicability

    This AD applies to Piaggio Aviation S.p.A. Model P-180 
airplanes, serial numbers (S/Ns) 1002, 1004 through 1234 inclusive, 
3001 through 3012 inclusive, and 3016, certificated in any category.

(d) Subject

    Joint Aircraft System Component (JASC) Code 5510, Horizontal 
Stabilizer Structure.

(e) Unsafe Condition

    This AD was prompted by a report of corrosion on the various 
aluminum alloy reinforcements in the horizontal stabilizer (HS) 
central box caused by a humid environment inside the box from water 
ingress and/or condensation. The FAA is issuing this AD to address 
this condition. The unsafe condition, if not addressed, could result 
in reduced structural integrity of the HS and loss of control of the 
airplane.

(f) Compliance

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

(g) Required Actions

    (1) Within the applicable compliance time specified in table 1 
to paragraph (g)(1) of this AD, do a detailed inspection of the HS 
central box for corrosion, in accordance with step (8), of Part A, 
of the Accomplishment Instructions in Piaggio Aerospace Service 
Bulletin 80-0489, Revision 2, dated November 30, 2022 (Piaggio SB 
80-0489, Revision 2), except you are not required to record any 
images.

     Table 1 to Paragraph (g)(1)--HS Central Box One Time Inspection
------------------------------------------------------------------------
                                         Compliance time (hours time-in-
                                         service (TIS) or calendar time,
          P-180 Serial number              whichever occurs first after
                                         February 2, 2024 (the effective
                                             date of AD 2023-25-03))
------------------------------------------------------------------------
1002; and 1034 through 3016 inclusive..  Within 220 hours TIS or 13
                                          months after February 2, 2024
                                          (the effective date of AD 2023-
                                          25-03).
1004 through 1033 inclusive............  Within 320 hours TIS or 13
                                          months after February 2, 2024
                                          (the effective date of AD 2023-
                                          25-03).
------------------------------------------------------------------------

    (2) If, during the inspection required by paragraph (g)(1) of 
this AD, any corrosion is detected, before next flight, contact 
either the Manager, International Validation Branch, FAA; European 
Union Aviation Safety Agency (EASA); or Piaggio's EASA Design 
Organization Approval (DOA), for an assessment of the corrosion 
level (level 1, 2, or 3).
    Note 1 to paragraph (g)(2): Appendix 1, Inspection Results Form, 
in Piaggio SB 80-

[[Page 8510]]

0489, Revision 2, may be used when contacting the FAA, EASA, or 
Piaggio's EASA DOA.
    (3) If level 1 corrosion is found during the inspection required 
by paragraph (g)(1) of this AD, no further action is required by 
this AD.
    (4) If level 2 corrosion is found during the inspection required 
by paragraph (g)(1) of this AD, do the action in either paragraph 
(g)(4)(i) or (ii) of this AD.
    (i) Before further flight, replace the HS assembly or repair the 
HS assembly in accordance with instructions from either the Manager, 
International Validation Branch, FAA; EASA; or Piaggio's EASA DOA. 
If approved by the DOA, the approval must include the DOA-authorized 
signature.
    (ii) Within 400 hours TIS or 12 months, whichever occurs first 
after the inspection required by paragraph (g)(1) of this AD, and 
thereafter at intervals not to exceed 400 hours TIS or 12 months, 
whichever occurs first after the most recent inspection, repeat the 
inspection required by paragraph (g)(1) of this AD. In addition, 
inspect the internal composite structure of the HS central box for 
surface cracks, distortion, and damage. After each repetitive 
inspection, before further flight, assess the inspection findings as 
required by paragraph (g)(2) of this AD. If it is determined that 
the level 2 corrosion has worsened since the last inspection; or if 
any surface cracks, distortion, or damage is found during any 
inspection; before further flight, replace the HS assembly or repair 
the HS assembly in accordance with instructions from either the 
Manager, International Validation Branch, FAA; EASA; or Piaggio's 
EASA DOA. If approved by the DOA, the approval must include the DOA-
authorized signature. These inspections must be repeated at 
intervals not to exceed 400 hours TIS or 12 months, whichever occurs 
first after the most recent inspection.
    (5) If level 3 corrosion is found during the inspection required 
by paragraph (g)(1) of this AD, do the actions required by paragraph 
(g)(5)(i) or (ii) of this AD.
    (i) Before further flight after the inspection required by 
paragraph (g)(1) of this AD, replace the HS assembly or repair the 
HS assembly in accordance with instructions from either the Manager, 
International Validation Branch, FAA; EASA; or Piaggio's EASA DOA. 
If approved by the DOA, the approval must include the DOA-authorized 
signature.
    (ii) Within 200 hours TIS or 6 months, whichever occurs first 
after the inspection required by paragraph (g)(1) of this AD, and 
thereafter at intervals not to exceed 200 hours TIS or 6 months, 
whichever occurs first after the most recent inspection, repeat the 
inspection required by paragraph (g)(1) of this AD. In addition, 
inspect the internal composite structure of the HS central box for 
surface cracks, distortion, and damage. After each repetitive 
inspection, before further flight, assess the inspection findings as 
required by paragraph (g)(2) of this AD. If it is determined that 
the level 3 corrosion has worsened since the last inspection; or if 
any surface cracks, distortion, or damage is found; before further 
flight, replace the HS assembly or repair the HS assembly in 
accordance with instructions from either the Manager, International 
Validation Branch, FAA; EASA; or Piaggio's EASA DOA. If approved by 
the DOA, the approval must include the DOA-authorized signature. 
These inspections must be repeated at intervals not to exceed 200 
hours TIS or 6 months, whichever occurs first after the most recent 
inspection, until a maximum of 660 hours TIS or 13 months, whichever 
occurs first after the inspection required by paragraph (g)(1) of 
this AD, at which time the HS assembly must be repaired or replaced.
    (6) Repair or replacement of the HS assembly is terminating 
action for the repetitive inspections required by paragraphs 
(g)(4)(ii) and (g)(5)(ii) of this AD.

(h) Credit for Previous Actions

    You may take credit for the actions required by paragraphs 
(g)(1) through (5) of this AD if you performed those actions before 
the effective date of this AD using Piaggio Aerospace Service 
Bulletin 80-0489, Revision 1, dated May 13, 2022.

(i) 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. 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 International Validation Branch, mail 
it to the address identified in paragraph (j) 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.

(j) Additional Information

    For more information about this AD, contact William McCully, 
Aviation Safety Engineer, FAA, 1600 Stewart Avenue, Suite 410, 
Westbury, NY 11590; phone: (404) 474-5548; email: 
[email protected].

(k) Material Incorporated by Reference

    (1) The Director of the Federal Register approved the 
incorporation by reference (IBR) of the material listed in this 
paragraph under 5 U.S.C. 552(a) and 1 CFR part 51.
    (2) You must use this material as applicable to do the actions 
required by this AD, unless the AD specifies otherwise.
    (3) The following material was approved for IBR on February 2, 
2024 (88 FR 90085, December 29, 2023).
    (i) Piaggio Aerospace Service Bulletin 80-0489, Revision 2, 
dated November 30, 2022.
    (ii) [Reserved]
    (4) For Piaggio material identified in this AD, contact Piaggio 
Aviation S.p.A., P180 Customer Support, via Pionieri e Aviatori 
d'Italia, snc--16154 Genoa, Italy; phone: +39 331 679 74 93; email: 
[email protected].
    (5) You may view this material 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.
    (6) You may view this material at the National Archives and 
Records Administration (NARA). For information on the availability 
of this material at NARA, visit www.archives.gov/federal-register/cfr/ibr-locations or email [email protected].

    Issued on January 24, 2025.
Victor Wicklund,
Deputy Director, Compliance & Airworthiness Division, Aircraft 
Certification Service.
[FR Doc. 2025-01968 Filed 1-29-25; 8:45 am]
BILLING CODE 4910-13-P
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