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Rule

You may be interested in this older document that published on 12/10/2025 with action 'Notice of proposed rulemaking (NPRM).' View Document

Airworthiness Directives; Baykar Piaggio Aerospace S.p.A. (Type Certificate Previously Held by Piaggio Aviation S.p.A.) Airplanes

A Rule by the Federal Aviation Administration on 03/23/2026

• 1.

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• Document Details Published Content - Document Details Agencies Department of Transportation Federal Aviation Administration Agency/Docket Numbers Docket No. FAA-2025-5027 Project Identifier MCAI-2025-00023-A Amendment 39-23283 AD 2026-05-10 CFR 14 CFR 39 Document Citation 91 FR 13706 Document Number 2026-05576 Document Type Rule Pages 13706-13708
  (3 pages) Publication Date 03/23/2026 RIN 2120-AA64 Published Content - Document Details

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• Document Details Published Content - Document Details Agencies Department of Transportation Federal Aviation Administration Agency/Docket Numbers Docket No. FAA-2025-5027 Project Identifier MCAI-2025-00023-A Amendment 39-23283 AD 2026-05-10 CFR 14 CFR 39 Document Citation 91 FR 13706 Document Number 2026-05576 Document Type Rule Pages 13706-13708
  (3 pages) Publication Date 03/23/2026 RIN 2120-AA64 Published Content - Document Details

• Document Dates Published Content - Document Dates Effective Date 2026-04-27 Dates Text This AD is effective April 27, 2026. Published Content - Document Dates

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  • AGENCY:
  • ACTION:
  • SUMMARY:
  • DATES:
  • ADDRESSES:
  • FOR FURTHER INFORMATION CONTACT:
  • SUPPLEMENTARY INFORMATION:
  • Background
  • Discussion of Final Airworthiness Directive
  • Comments
  • Explanation of Change To Type Certificate Holder Name
  • Conclusion
  • Material Incorporated by Reference Under 1 CFR Part 51
  • Differences Between This AD and the Referenced Material
  • Costs of Compliance
  • Authority for This Rulemaking
  • Regulatory Findings
  • List of Subjects in 14 CFR Part 39
  • The Amendment
  • PART 39—AIRWORTHINESS DIRECTIVES
  • (a) Effective Date
  • (b) Affected ADs
  • (c) Applicability
  • (d) Subject
  • (e) Unsafe Condition
  • (f) Compliance
  • (g) Required Actions
  • (h) No Reporting Requirement
  • (i) Alternative Methods of Compliance (AMOCs)
  • (j) Additional Information
  • (k) Material Incorporated by Reference Enhanced Content - Table of Contents

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| Docket No. FAA-2025-5027
(2 Documents) | | | |
| --- | | | |
| Date | | Action | Title |
| | 2026-03-23 | Final rule. | Airworthiness Directives; Baykar Piaggio Aerospace S.p.A. (Type Certificate Previously Held by Piaggio Aviation S.p.A.) Airplanes |
| | 2025-12-10 | Notice of proposed rulemaking (NPRM). | Airworthiness Directives; Piaggio Aviation S.p.A. Airplanes |

| Project Identifier MCAI-2025-00023-A
(2 Documents) | | | |
| --- | | | |
| Date | | Action | Title |
| | 2026-03-23 | Final rule. | Airworthiness Directives; Baykar Piaggio Aerospace S.p.A. (Type Certificate Previously Held by Piaggio Aviation S.p.A.) Airplanes |
| | 2025-12-10 | Notice of proposed rulemaking (NPRM). | Airworthiness Directives; Piaggio Aviation S.p.A. Airplanes |

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Department of Transportation

Federal Aviation Administration

1. 14 CFR Part 39
2. [Docket No. FAA-2025-5027; Project Identifier MCAI-2025-00023-A; Amendment 39-23283; AD 2026-05-10]
3. RIN 2120-AA64 ( printed page 13706) # AGENCY:

Federal Aviation Administration (FAA), DOT.

ACTION:

Final rule.

SUMMARY:

The FAA is adopting a new airworthiness directive (AD) for certain Baykar Piaggio Aerospace S.p.A. (type certificate previously held by Piaggio Aviation S.p.A.) (Piaggio) Model P-180 airplanes. This AD was prompted by a report of chafing in the flap transmission shafts. This AD requires inspecting the flap transmission shaft for chafing or any damage (surface abrasions, grooves or rubbing tracks, and metallic smears or transfers), measuring specific gaps, and, depending on findings, accomplishing applicable corrective actions. The FAA is issuing this AD to address the unsafe condition on these products.

DATES:

This AD is effective April 27, 2026.

The Director of the Federal Register approved the incorporation by reference of a certain publication listed in this AD as of April 27, 2026.

ADDRESSES:

AD Docket: You may examine the AD docket at regulations.gov under Docket No. FAA-2025-5027; 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 mandatory continuing airworthiness information (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 Piaggio Aerospace material identified in this AD, contact Piaggio, P180 Customer Support, via Pionieri e Aviatori d'Italia, snc—16154 Genoa, Italy; phone: +39 331 679 74 93; email: technicalsupport@piaggioaerospace.it.
• 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:

Frank Huynh, Aviation Safety Engineer, FAA, 1600 Stewart Avenue, Suite 410, Westbury, NY 11590; phone: (404) 983-5288; email: frank.huynh@faa.gov.

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 Piaggio Aviation S.p.A. (type certificate currently held by Baykar Piaggio Aerospace S.p.A.) Model P-180 airplanes. The NPRM was published in the Federal Register on December 10, 2025 (90 FR 57170). The NPRM was prompted by European Union Aviation Safety Agency (EASA) AD 2025-0014, dated January 13, 2025 (EASA AD 2025-0014) (also referred to as the MCAI), issued by EASA, which is the Technical Agent for the Member States of the European Union. The MCAI states that an occurrence was reported where, during scheduled airplane maintenance, chafing was detected on the flap transmission shafts. A subsequent investigation identified a limited clearance between flap transmission shafts 1 and 7 and the wing rib at wing station 440 and between flap transmission shaft 7 and the cabin door seal inflation system pneumatic pipe. This condition, if not detected and corrected, could affect the integrity of the flap transmission and lead to reduced control of the airplane.

In the NPRM, the FAA proposed to require inspecting the flap transmission shafts for chafing or any damage (surface abrasions, grooves or rubbing tracks, and metallic smears or transfers), measuring specific gaps, and, depending on the findings, accomplishing corrective actions. 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-2025-5027.

Discussion of Final Airworthiness Directive

Comments

The FAA received no comments on the NPRM or on the determination of the costs.

Explanation of Change To Type Certificate Holder Name

The FAA has revised the applicability of this AD to identify the type certificate holder's name as published in the most recent type certificate data sheet for the affected models.

Conclusion

These products have been approved by the civil 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, that authority has notified the FAA of the unsafe condition described in the MCAI referenced above. 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 minor editorial changes, this AD is adopted as proposed in the NPRM. None of the changes will increase the economic burden on any operator.

Material Incorporated by Reference Under 1 CFR Part 51

The FAA reviewed Piaggio Aerospace Service Bulletin (SB) 80-0498, Revision 0, dated August 2, 2024 (Piaggio SB 80-0498, Revision 0). This material specifies procedures for inspecting the flap transmission shaft for chafing or any damage (surface abrasions, grooves or rubbing tracks, and metallic smears or transfers), measuring specific gaps, and depending on findings, accomplishing applicable corrective actions. 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.

Differences Between This AD and the Referenced Material

The referenced material requires contacting Piaggio for approved repair instructions. This AD requires contacting either the Manager, International Validation Branch, FAA; EASA; or Piaggio's EASA Design Organization Approval (DOA), for approved repair instructions.

Costs of Compliance

The FAA estimates that this AD affects 98 airplanes of U.S. registry.

The FAA estimates the following costs to comply with this AD: ( printed page 13707)

| Action | Labor cost | Parts cost | Cost per
product | Cost on U.S
operators |
| --- | --- | --- | --- | --- |
| Initial inspection of flap transmission shafts | 28 work-hours × $85 per hour = $2,380 | $0 | $2,380 | $233,240 |
The FAA estimates the following costs to do any rework, repairs or replacements that would be required based on the results of the inspection. Any corrective action that may be needed as a result of the inspection can vary from airplane to airplane. The agency has no way of determining the number of airplanes that might need this rework, repairs, or replacements:

| Action | Labor cost | Parts cost | Cost per product |
| --- | --- | --- | --- |
| Repetitive inspections of flap transmission shafts | 28 work-hours × $85 per hour = $2,380, per inspection | $0 | $2,380, per inspection. |
| Rework of wing rib(s) | 40 work-hours × $85 per hour = $3,400, per rework | 0 | $3,400, per rework. |
| Repair of pneumatic pipe | 20 work-hours × $85 per hour = $1,700, per repair | 0 | $1,700, per repair. |
| Replacement of flap transmission shaft (all four) | 20 work-hours × $85 per hour = $1,700 | 21,282 | $22,982. |

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

1. The authority citation for part 39 continues to read as follows:

Authority: 49 U.S.C. 106(g), 40113, 44701.

§ 39.13 [Amended] 2. The FAA amends § 39.13 by adding the following new airworthiness directive:

2026-05-10 Baykar Piaggio Aerospace S.p.A. (Type Certificate Previously Held by Piaggio Aviation S.p.A.): Amendment 39-23283; Docket No. FAA-2025-5027; Project Identifier MCAI-2025-00023-A.

(a) Effective Date

This airworthiness directive (AD) is effective April 27, 2026.

(b) Affected ADs

None.

(c) Applicability

This AD applies to Baykar Piaggio Aerospace S.p.A. (type certificate previously held by Piaggio Aviation S.p.A.) Model P-180 airplanes, serial numbers 1002, 1004 through 3016, and 3018, certificated in any category.

(d) Subject

Joint Aircraft System Component (JASC) Code 2700, Flight Control System.

(e) Unsafe Condition

This AD was prompted by a report of chafing in the flap transmission shafts. The FAA is issuing this AD to detect and address chafing or any damage (surface abrasions, grooves or rubbing tracks, and metallic smears or transfers) in the flap transmission shafts. The unsafe condition, if not addressed, could affect the integrity of the flap transmission, which could lead to reduced control of the airplane.

(f) Compliance

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

(g) Required Actions

(1) Within 220 hours time-in-service (TIS) after the effective date of this AD, inspect the outboard and inboard flap transmission shafts (#1 and #7) at the crossing holes and openings on wing rib 440 and inspect the left-hand (LH) inboard flap transmission shaft (#7) and the pneumatic pipe for chafing or any damage (surface abrasions, grooves or rubbing tracks, and metallic smears or transfers). Additionally, measure the gaps between the outboard and inboard flap transmission shafts (#1 and #7) and their respective crossing holes and openings on wing rib 440, and the gap between the LH inboard flap transmission shaft (#7) and the pneumatic pipe. Perform these actions in accordance with the ACCOMPLISHMENT INSTRUCTIONS, paragraph B. PROCEDURE/MODIFICATION, steps (10) and (11) in Piaggio Aerospace Service Bulletin (SB) 80-0498, Revision 0, dated August 2, 2024 (Piaggio SB 80-0498, Revision 0).

(2) If chafing or any damage (surface abrasions, grooves or rubbing tracks, and metallic smears or transfers) (referred to as discrepancies) is found during the inspections required by paragraph (g)(1) of ( printed page 13708) this AD, perform any rework, repair, replacement, and repetitive inspections, as applicable, as specified in paragraphs (g)(2)(i) through (iv) of this AD.

(i) If no discrepancies are found or discrepancies are found that meet the criteria in Case 1 of paragraph 14 of Part A, paragraph B. PROCEDURE/MODIFICATION, of the ACCOMPLISHMENT INSTRUCTIONS section in Piaggio SB 80-0498, Revision 0, no further action is required by this AD.

(ii) If discrepancies are found that meet the criteria in Case 2 of paragraph 14 of Part A, paragraph B. PROCEDURE/MODIFICATION, of the ACCOMPLISHMENT INSTRUCTIONS section in Piaggio SB 80-0498, Revision 0, accomplish the actions of paragraph (g)(2)(ii)(A) and (B):

(A) Repetitively perform the inspections of paragraph (g)(1) at intervals not to exceed 220 hours TIS until the rework required by paragraph (g)(2)(ii)(B) of this AD is done.

(B) Within 660 hours TIS after the initial inspection required by paragraph (g)(1) of this AD, rework the wing rib(s) 440 (LH part number (P/N) 80-201367-001, right-hand (RH) P/N 80-201367-002) in accordance with Steps 14 through 21 of Part A and Part B, paragraph B. PROCEDURE/MODIFICATION, of the ACCOMPLISHMENT INSTRUCTIONS section in Piaggio SB 80-0498, Revision 0.

(iii) If discrepancies are found that meet the criteria in Case 3 of paragraph 14 of Part A, paragraph B. PROCEDURE/MODIFICATION, of the ACCOMPLISHMENT INSTRUCTIONS section in Piaggio SB 80-0498, Revision 0, accomplish the actions of paragraph (g)(2)(iii)(A) and (B):

(A) Repetitively perform the inspections of paragraph (g)(1) of this AD at intervals not to exceed 110 hours TIS until the rework required by paragraph (g)(2)(iii)(B) of this AD is done.

(B) Within 220 hours TIS after the initial inspection required by paragraph (g)(1) of this AD, rework the wing rib(s) 440 (LH P/N 80-201367-001, RH P/N 80-201367-002) in accordance with Steps 14 through 21 of Part A and Part B, paragraph B. PROCEDURE/MODIFICATION, of the ACCOMPLISHMENT INSTRUCTIONS section in Piaggio SB 80-0498, Revision 0.

(iv) If discrepancies are found that meet the criteria in Case 4 of paragraph 14 of Part A, paragraph B. PROCEDURE/MODIFICATION, of the ACCOMPLISHMENT INSTRUCTIONS section in Piaggio SB 80-0498, Revision 0, before further flight, perform the following:

(A) Rework the wing rib(s) 440 (LH P/N 80-201367-001, RH P/N 80-201367-002) in accordance with Steps 14 through 21 of Part A and Part B, paragraph B. PROCEDURE/MODIFICATION, of the ACCOMPLISHMENT INSTRUCTIONS section in Piaggio SB 80-0498, Revision 0.

(B) Repair the pneumatic pipe (P/N 80-207493-401 ) in accordance with Steps 22 through 42 of Part B, paragraph B. PROCEDURE/MODIFICATION, of the ACCOMPLISHMENT INSTRUCTIONS section in Piaggio SB 80-0498, Revision 0.

(C) Replace any damaged transmission shaft with an airworthy one.

(3) If clearance cannot be obtained during Steps 21, 41, or 42 of Part B, paragraph B. PROCEDURE/MODIFICATION, of the ACCOMPLISHMENT INSTRUCTIONS section in Piaggio SB 80-0498, Revision 0, as required by paragraphs (g)(2)(ii)(B), (g)(2)(iii)(B), or (g)(2)(iv)(B) of this AD, contact the Manager, International Validation Branch, FAA; the European Union Aviation Safety Agency (EASA); or Piaggio's EASA Design Organization Approval (DOA) for approved repair instructions, and before further flight, perform the repair. If the repair is approved by the DOA, the approval must include the DOA-authorized signature.

(h) No Reporting Requirement

Although Piaggio SB 80-0498, Revision 0, specifies to submit certain information to the manufacturer, this AD does not include that requirement.

(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, send it to the attention of the person identified in paragraph (j) of this AD and email to: AMOC@faa.gov. 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 Frank Huynh, Aviation Safety Engineer, FAA, 1600 Stewart Avenue, Suite 410, Westbury, NY 11590; phone: (404) 983-5288; email: frank.huynh@faa.gov.

(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.

(i) Piaggio Aerospace Service Bulletin 80-0498, Revision 0, dated August 2, 2024.

(ii) [Reserved]

(3) For Piaggio Aerospace material identified in this AD, contact Baykar Piaggio Aerospace S.p.A., P180 Customer Support, via Pionieri e Aviatori d'Italia, snc—16154 Genoa, Italy; phone: +39 331 679 74 93; email: technicalsupport@piaggioaerospace.it.

(4) 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.

(5) 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 fr.inspection@nara.gov.

Issued on March 17, 2026.

Steven W. Thompson,

Acting Deputy Director, Compliance & Airworthiness Division, Aircraft Certification Service.

[FR Doc. 2026-05576 Filed 3-20-26; 8:45 am]

BILLING CODE 4910-13-P

Published Document: 2026-05576 (91 FR 13706)