# [Amended]
**AGENCY:**
Federal Aviation Administration (FAA), DOT.
**ACTION:**
Notice of proposed rulemaking (NPRM).
**SUMMARY:**
The FAA proposes to adopt a new airworthiness directive (AD) for certain Embraer S.A. (Embraer) Model EMB-505 airplanes. This proposed AD was prompted by the possibility that some airplanes may have invalid horizontal stabilizer (HS) backlash test results due to the use of incorrect procedures. This proposed AD would require inspecting the airplane's left-hand (LH) and right-hand (RH) HS backlash and replacement, as applicable, of certain hinge point and pitch trim actuator attachment parts and the pitch trim actuator. The FAA is proposing this AD to address the unsafe condition on these products.
**DATES:**
The FAA must receive comments on this NPRM by January 2, 2026.
**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-2025-3993; 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 mandatory continuing airworthiness information (MCAI), any comments received, and other information. The street address for Docket Operations is listed above.
*Material Incorporated by Reference:*
• For Agência Nacional de Aviação Civil (ANAC) material identified in this proposed AD, contact ANAC, Continuing Airworthiness Technical Branch (GTAC), Rua Doutor Orlando Feirabend Filho, 230—Centro Empresarial Aquarius—Torre B—Andares 14 a 18, Parque Residencial Aquarius, CEP 12.246-190—São José dos Campos—SP, Brazil; phone: 55 (12) 3203-6600; email: *[email protected]* ; website: *anac.gov.br/en/* . You may find this material on the ANAC website at *sistemas.anac.gov.br/certificacao/DA/DAE.asp* .
• 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:**
Jim Rutherford, Aviation Safety Engineer, FAA, 1600 Stewart Avenue, Suite 410, Westbury, NY 11590; phone: (816) 329-4165; 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 using a method listed under *ADDRESSES* . Include “Docket No. FAA-2025-3993; Project Identifier MCAI-2025-00630-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 this 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 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 Jim Rutherford, 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**
ANAC, which is the aviation authority for Brazil, has issued ANAC AD 2025-04-01, dated April 15, 2025 (ANAC AD 2025-04-01) (also referred to as the MCAI), to correct an unsafe condition on certain serial-numbered Embraer Model EMB-505 airplanes. The MCAI states that there is a possibility of some airplanes having invalid HS backlash test results due to the use of incorrect test procedures. The excessive backlash may result in an aeroelastic phenomenon exposing the surrounding structure and systems to unacceptable vibration levels and reduced controllability of the airplane. To address this unsafe condition, the MCAI specifies inspecting the airplane LH and RH HS backlash and replacing, as applicable, the LH and RH hinge point attachment parts, the LH or RH pitch trim actuator rod-end attachment parts, and the pitch trim actuator.
You may examine the MCAI in the AD docket at *regulations.gov* under Docket No. FAA-2025-3993.
**Material Incorporated by Reference Under 1 CFR part 51**
The FAA reviewed ANAC AD 2025-04-01, which specifies procedures for inspecting the LH and RH HS backlash for correct values, and replacing, as applicable, the LH and RH hinge point attachment parts, the LH or RH pitch trim actuator rod-end attachment parts, and the pitch trim actuator.
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 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 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 would require accomplishing the actions specified in ANAC AD 2025-04-01 described previously, except for any differences identified as exceptions in the regulatory text of this proposed AD. See “Differences Between this Proposed AD and the MCAI” for a general discussion of these differences.
**Differences Between This Proposed AD and the MCAI**
The material specified in ANAC AD 2025-04-01 allows the use of alternative or similar parts in place of the ones specified in the kits, provided these alternative or similar parts are approved by Embraer, but this proposed AD would require approval from either the Manager, International Validation Branch, FAA; ANAC; or ANAC's authorized Designee. If approved by the ANAC Designee, the approval must include the Designee's authorized signature.
**Explanation of Required Compliance Information**
In the FAA's ongoing efforts to improve the efficiency of the AD process, the FAA developed a process to use some civil aviation authority (CAA) ADs as the primary source of information for compliance with requirements for corresponding FAA ADs. The FAA has been coordinating this process with manufacturers and CAAs. As a result, the FAA proposes to incorporate ANAC AD 2025-04-01 by reference in the FAA final rule. This proposed AD would, therefore, require compliance with ANAC AD 2025-04-01 in its entirety through that incorporation, except for any differences identified as exceptions in the regulatory text of this proposed. Material required by ANAC AD 2025-04-01 for compliance will be available at *regulations.gov* under Docket No. FAA-2025-3993 after the FAA final rule is published.
**Costs of Compliance**
The FAA estimates that this AD, if adopted as proposed, would affect 50 airplanes of U.S. registry.
The FAA estimates the following costs to comply with this proposed AD:
| Action | Labor cost | Parts cost | Cost per | Cost on U.S. |
| --- | --- | --- | --- | --- |
| Inspect HS backlash | 16 work-hours × $85 per hour = $1,360 | $0 | $1,360 | $68,000 |
The FAA estimates the following costs to do any necessary actions that would be required based on the results of the proposed inspection. The agency has no way of determining the number of airplanes that might need these actions:
| Action | Labor cost | Parts cost | Cost per |
| --- | --- | --- | --- |
| Replace horizontal to vertical stabilizers LH hinge point attachment parts | 17 work-hours × $85 per hour = $1,445 | $300 | $1,745 |
| Replace horizontal to vertical stabilizers RH hinge point attachment parts | 17 work-hours × 85 per hour = 1,445 | 350 | 1,795 |
| Replace RH pitch trim actuator rod-end attachment parts | 16 work-hours × 85 per hour = 1,360 | 400 | 1,760 |
| Replace LH pitch trim actuator rod-end attachment parts | 16 work-hours × 85 per hour = 1,360 | 400 | 1,760 |
| Replace pitch trim actuator | 18 work-hours × 85 per hour = 1,530 | 5,000 | 6,530 |
The FAA has included all known costs in its cost estimate. According to the manufacturer, however, all of the costs of this proposed 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**
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 this 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**
1. The authority citation for part 39 continues to read as follows:
**Authority:**
49 U.S.C. 106(g), 40113, 44701.
§ 39.13
2. The FAA amends § 39.13 by adding the following new airworthiness directive:
*Embraer S.A.:* Docket No. FAA-2025-3993; Project Identifier MCAI-2025-00630-A.
**(a) Comments Due Date**
The FAA must receive comments on this airworthiness directive (AD) by January 2, 2026.
**(b) Affected ADs**
None.
**(c) Applicability**
This AD applies to Embraer S.A. Model EMB-505 airplanes, as identified in Agência Nacional de Aviação Civil (ANAC) AD 2025-04-01, effective April 15, 2025 (ANAC AD 2025-04-01), certificated in any category.
**(d) Subject**
Joint Aircraft System Component (JASC) Code 2700, Flight Control System.
**(e) Unsafe Condition**
This AD was prompted by the discovery that some airplanes may have invalid horizontal stabilizer (HS) backlash test results due to incorrect procedures being performed. The FAA is issuing this AD to address the unsafe condition. The unsafe condition, if not addressed, could result in unacceptable vibration levels and reduced controllability of the airplane.
**(f) Compliance**
Comply with this AD within the compliance times specified, unless already done.
**(g) Required Actions**
Except as specified in paragraphs (h) and (i) of this AD: Comply with all required actions and compliance times specified in, and in accordance with, ANAC AD 2025-04-01.
**(h) Exceptions to ANAC AD 2025-04-01**
(1) Where ANAC AD 2025-04-01 refers to its effective date, this AD requires using the effective date of this AD for both Group 1 and Group 2 airplanes.
(2) Where the material specified in ANAC AD 2025-04-01 allows the use of alternative or similar parts in place of the ones specified in the kits, provided these alternative or similar parts are approved by Embraer, this AD requires approval from either the Manager, International Validation Branch, FAA; ANAC; or ANAC's authorized Designee. If approved by the ANAC Designee, the approval must include the Designee's authorized signature.
(3) Where ANAC AD 2025-04-01 refers to removal and replacement of attachment parts and pitch trim actuators in paragraphs (b)(1), (c)(1), (d)(1), (d)(2), (e)(1), (e)(2), and (f)(1), this AD specifies accomplishing the removal and replacement in these paragraphs in accordance with the appropriate procedures contained in the material referenced in ANAC AD 2025-04-01.
(4) Where the material referenced in ANAC AD 2025-04-01 specifies discarding parts, this AD requires removing those parts from service.
(5) This AD does not adopt paragraph (h) of ANAC AD 2025-04-01.
**(i) No Reporting Requirement**
Although the material referenced in ANAC AD 2025-04-01 specifies to submit information to the manufacturer, this AD does not require that action.
**(j) Credit for Previous Actions**
This paragraph provides credit for the actions required by paragraph (g) of this AD, if those actions were performed before the effective date of this AD using Embraer Service Bulletin No. 505-27-0034, dated September 19, 2024, or Embraer Service Bulletin No. 505-27-0034, Revision 01, dated October 04, 2024.
**(k) Alternative Methods of Compliance (AMOCs)**
(1) 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 (l) of this AD and email to: *[email protected]* .
(2) 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.
**(l) Additional Information**
For more information about this AD, contact Jim Rutherford, Aviation Safety Engineer, FAA; phone: (816) 329-4165; email: *[email protected]* .
**(m) 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) Agência Nacional de Aviação Civil AD 2025-04-01, effective April 15, 2025.
(ii) [Reserved]
(3) For Embraer S.A. material identified in this AD, contact Embraer S.A., Technical Publications Avenida Brigadeiro Faria Lima, 2170, São Jose dos Campos—SP, Brazil; phone: +551239275852; email: *[email protected];* website: *https://www.flyembraer.com/irj/portal* .
(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 *[email protected]* .
Issued on October 24, 2025.
Steven W. Thompson,
Acting Deputy Director, Compliance & Airworthiness Division, Aircraft Certification Service.