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 Model P-180 airplanes. The NPRM was published in the Federal Register on January 21, 2026 (91 FR 2507). The NPRM was prompted by European Union Aviation Safety Agency (EASA) AD 2025-0054, dated March 6, 2025 (EASA AD 2025-0054) (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 corrosion and cracks affecting the vertical stabilizer were reported on Model P-180 airplanes. This condition, if not addressed, could result in reduced structural integrity of the vertical stabilizer and the rudder with consequent reduced control of the airplane. In the NPRM, the FAA proposed to require repetitive visual and NDT inspections, a one-time NDT inspection of the vertical stabilizer assembly, and, depending on findings, accomplishment of corrective actions. The FAA also proposed to provide a terminating action for the repetitive inspections. 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-2026-0019. Discussion of Final Airworthiness Directive Comments The FAA received a comment from one commenter. The commenter was the Air Line Pilots Association, International, who supported the NPRM without change. 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) 80-0493, Revision 0, dated November 21, 2024 (Piaggio Aerospace SB 80-0493, Rev. 0). This material specifies procedures for repetitive visual and NDT (including high-frequency eddy current (HFEC) and film radiographic (FR/D2) testing) inspections, a one-time NDT inspection, and post-repair instructions for the parts and structural elements of the vertical stabilizer assembly for evidence of damage of the protective finish, corrosion, and cracking, and applicable corrective actions. Corrective actions include, depending on inspection findings, repairing or replacing affected parts or contacting Piaggio to obtain an approved Repair Design Approval Sheet (RDAS), which is terminating action for certain repetitive inspections. 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 Step (49) of Piaggio Aerospace SB 80-0493, Rev. 0, provides instructions to contact Piaggio to obtain an approved RDAS and accomplish that repair accordingly, including post-repair follow-on action(s), as applicable. This AD instead requires contacting either the Manager, International Validation Branch, FAA; EASA; or Piaggio's EASA Design Organization Approval (DOA) for approved repair instructions and, within the compliance time specified therein, accomplish those instructions accordingly, including post-repair follow-on action(s), as applicable. If approved by the DOA, the approval must include the DOA-authorized signature. Although Piaggio Aerospace SB 80-0493, Rev. 0, states that certain subsequent inspections are in accordance with the aircraft maintenance manual inspection program chapter 05-20-00, this AD does not require those actions. Although steps (17), (20), (24), (28), (33), (38), (41), (44), (47), (48), and Note 21 of Piaggio Aerospace SB 80-0493, Rev. 0, require reporting inspection results to Piaggio, this AD does not require those actions. Costs of Compliance The FAA estimates that this AD affects 107 airplanes of U.S. registry. The FAA estimates the following costs to comply with this AD: Estimated Costs Action Labor cost Parts cost Cost per product Cost on U.S. operators One-time NDT inspection of the vertical stabilizer assembly Up to 27 work-hours × $85 per hour = $2,295 $0 Up to $2,295 Up to $245,565. Repetitive visual and NDT inspections of the vertical stabilizer assembly Up to 40 work-hours × $85 per hour = $3,400 (per inspection) $0 (per inspection) Up to $3,400 (per inspection) Up to $363,800 (per inspection). The FAA estimates the following costs to do any repairs that would be required based on the results of the inspections. The agency has no way of determining the number of airplanes that might need these repairs: On-Condition Costs Action Labor cost Parts cost Cost per product Repair of parts and structural elements of the vertical stabilizer assembly Up to 280 work-hours × $85 per hour = $23,800 Up to $1,000 Up to $24,800. Replace parts and structural elements of the vertical stabilizer assembly Up to 160 work-hours × $85 per hour = $13,600 Up to $10,000 Up to $23,600. 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: 2026-06-05 Baykar Piaggio Aerospace S.p.A. (type certificate previously held by Piaggio Aviation S.p.A.): Amendment 39-23294; Docket No. FAA-2026-0019; Project Identifier MCAI-2025-00293-A. (a) Effective Date This airworthiness directive (AD) is effective May 11, 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, manufacturer serial numbers 1002, 1004 through 3016, and 3018, certificated in any category. (d) Subject Joint Aircraft System Component (JASC) Code 5530, Vertical Stabilizer Structure. (e) Unsafe Condition This AD was prompted by reports of corrosion and cracks affecting the vertical stabilizer. The FAA is issuing this AD to address this unsafe condition. The unsafe condition, if not addressed, could result in reduced structural integrity of the vertical stabilizer and the rudder with consequent reduced 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 and thereafter at intervals not to exceed 660 hours time-in-service (TIS) or 26 months, whichever occurs first, do the applicable repetitive visual and non-destructive testing (NDT) inspections of the parts of the vertical stabilizer assembly for evidence of damage to the protective finish, corrosion, and cracking, in accordance with section 2.B, PART A, items (i) through (vii) as applicable, of Piaggio Aerospace Service Bulletin (SB) 80-0493, Revision 0, dated November 21, 2024 (Piaggio Aerospace SB 80-0493, Rev. 0). Where Piaggio Aerospace SB 80-0493, Rev. 0, states that subsequent inspections shall be performed in accordance with the aircraft maintenance manual inspection program chapter 05-20-00, this AD does not require those actions. Table 1 to Paragraph ( g )(1)-Compliance Times P-180 Serial No. Compliance time (hours TIS or calendar time, whichever occurs first after the effective date of this AD) 1002, 1004 through 3016 Within 220 hours TIS or 13 months. 3018 Within 660 hours TIS or 26 months. (2) Within the applicable compliance time specified in table 1 to paragraph (g)(1) of this AD, do the applicable one-time NDT inspections of the parts of the vertical stabilizer assembly for evidence of damage to the protective finish, corrosion and cracking, in accordance with section 2.B, PART A, items (viii) and (ix), as applicable, of Piaggio Aerospace SB 80-0493, Rev. 0. (3) If, during any inspection required by paragraph (g)(1) or (2) of this AD any corrosion or cracking is found, before further flight, accomplish the applicable corrective action(s), including post-repair inspections, in accordance with the instructions of section 2.B, PART B, of Piaggio Aerospace SB 80-0493, Rev. 0. (4) Where the Accomplishment Instructions, section 2.B, PART B, step (49) of Piaggio SB 80-0493, Rev. 0, state to contact Piaggio to obtain an approved repair design approval sheet (RDAS) and accomplish that repair accordingly including post-repair follow-on actions(s), as applicable, before further flight, contact either the Manager, International Validation Branch, FAA; European Union Aviation Safety Agency (EASA); or Piaggio's EASA Design Organization Approval (DOA) for approved repair instructions and, within the compliance time specified therein, accomplish those instructions accordingly, including post-repair follow-on action(s), as applicable. If approved by the DOA, the approval must include the DOA-authorized signature. (h) Terminating Action Accomplishment of any action identified as "terminating action" for a given inspection in section 2.B, PART B, of Piaggio Aerospace SB 80-0493, Rev. 0, constitutes terminating action for the repetitive inspections, as applicable, required by paragraph (g)(1) of this AD for that airplane. (i) No Reporting Requirement Although certain steps of Piaggio Aerospace SB 80-0493, Rev. 0, specify to submit inspection findings to the manufacturer, this AD does not include that requirement. (j) 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 (k) 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. (k) Additional Information For more information about this AD, contact Doug Rudolph, Aviation Safety Engineer, FAA, 1600 Stewart Avenue, Suite 410, Westbury, NY 11590; phone: (816) 329-4059; email: doug.rudolph@faa.gov. (l) Material Incorporated by Reference (1) The Director of the Federal Register approved the incorporation by reference 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 80-0493, Revision 0, dated November 21, 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 19, 2026. Steven W. Thompson, Acting Deputy Director, Compliance & Airworthiness Division, Aircraft Certification Service.