# [Amended]
**AGENCY:**
Federal Aviation Administration (FAA), DOT.
**ACTION:**
Final rule.
**SUMMARY:**
The FAA is superseding Airworthiness Directive (AD) 2021-22-12 for certain Honda Aircraft Company LLC (Honda) Model HA-420 airplanes. AD 2021-22-12 required removing and cleaning the inner diameter of the flap control pushrod assemblies and repetitively applying corrosion inhibiting compound (CIC) to this area. Since the FAA issued AD 2021-22-12, new flap control pushrods have been approved that are more corrosion resistant and do not require repetitive CIC applications. In addition, referenced service material has been updated to a new revision that includes redesigned replacement flap control pushrod assemblies that have been modified to prevent interference with adjacent parts. This AD retains the requirements of AD 2021-22-12 and requires replacing the flap control pushrod assemblies with improved design pushrod assemblies for all airplanes affected by AD 2021-22-12, as well as for other airplanes not affected by AD 2021-22-12. The FAA is issuing this AD to address the unsafe condition on these products.
**DATES:**
This AD is effective May 8, 2026.
The Director of the Federal Register approved the incorporation by reference of a certain publication listed in this AD as of May 8, 2026.
The Director of the Federal Register approved the incorporation by reference of a certain publication listed in this AD as of November 19, 2021 (86 FR 60753, November 4, 2021).
**ADDRESSES:**
*AD Docket:* You may examine the AD docket at *regulations.gov* under Docket No. FAA-2025-0485; 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, 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 Honda Aircraft Company material identified in this AD, contact Honda, 6430 Ballinger Road, Greensboro, NC 27410; phone: (336) 662-0246; website: *hondajet.com.*
• You may view this material at the FAA, 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-2025-0485.
**FOR FURTHER INFORMATION CONTACT:**
Kelly Fichter, Aviation Safety Engineer, FAA, 1701 Columbia Avenue, College Park, GA 30337: (404) 474-5544; email: *[email protected].*
**SUPPLEMENTARY INFORMATION:**
**Background**
The FAA issued a notice of proposed rulemaking (NPRM) to amend 14 CFR part 39 to supersede AD 2021-22-12, Amendment 39-21785 (86 FR 60753, November 4, 2021) (AD 2021-22-12). AD 2021-22-12 applied to certain Honda Model HA-420 airplanes. AD 2021-22-12 required removing and cleaning the inner diameter of the flap control pushrods and repetitively applying CIC to this area to prevent corrosion. The NPRM was published in the *Federal Register* on April 11, 2025 (90 FR 15426). The NPRM was prompted by the manufacturer developing improved flap control pushrods that are more corrosion resistant and do not require repetitive CIC applications. The manufacturer also determined that the applicability should be expanded to include airplanes with serial number 42000211, 42000212, and 42000215 through 42000287, as these airplanes also have an affected flap pushrod assembly installed.
The FAA issued a supplemental notice of proposed rulemaking (SNPRM) to amend 14 CFR part 39 to supersede AD 2021-22-12. The SNPRM was published in the *Federal Register* on December 23, 2025 (90 FR 60029). The SNPRM was prompted by the discovery that the updated outboard corrosion resistant pushrods could interfere with the mid flap drive arms when fully deployed. As a result of this finding, the manufacturer published updated service material that includes a modified design of the flap control pushrod assembly to prevent interference with adjacent parts. In the SNPRM, the FAA proposed to require retaining all of the requirements of AD 2021-22-12. The SNPRM also proposed to require expanding the applicability to include additional airplanes, and replacing the flap control pushrod assemblies with new corrosion-resistant flap control pushrod assemblies as terminating action for the repetitive CIC applications required by AD 2021-22-12. The FAA is issuing this AD to address the unsafe condition on these products.
**Discussion of Final Airworthiness Directive**
**Comments**
The FAA received no comments on the SNPRM or on the determination of the costs.
**Conclusion**
The FAA reviewed the relevant data and determined that air safety requires adopting the AD as proposed. Accordingly, the FAA is issuing this AD to address the unsafe condition on these products. This AD is adopted as proposed in the SNPRM.
**Material Incorporated by Reference Under 1 CFR Part 51**
The FAA reviewed Honda Aircraft Company Alert Service Bulletin No. SB-420-27-009, Revision B, dated August 5, 2025. This material specifies procedures for replacing the flap control pushrod assemblies with improved design flap control pushrod assemblies.
This AD also requires Honda Aircraft Company Alert Service Bulletin No. SB-420-27-008, dated August 31, 2021, which the Director of the Federal Register approved for incorporation by reference as of November 19, 2021 (86 FR 60753, November 4, 2021).
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.
**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:
| Action | Labor cost | Parts cost | Cost per | Cost on U.S. |
| --- | --- | --- | --- | --- |
| Remove, clean, and apply CIC to the flap control pushrod assembly (retained from AD 2021-22-12) | 22 work-hours × $85 per hour = $1,870 | $70 | $1,940 | $85,360 (44 airplanes). |
| Reapply CIC every 90 days (cost for each time) (retained from AD 2021-22-12) | 1 work-hour × $85 per hour = $85 | 70 | 155 | $6,820 (44 airplanes). |
| Replace the left and right inboard flap control pushrod assemblies | 22 work-hours × $85 per hour = $1,870 | 5,168 | 7,038 | $753,066 (107 airplanes). |
The FAA has included all known costs in its cost estimate. According to the manufacturer, however, some or all of the costs of this 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**
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**
**14 CFR Part 39**
1. The authority citation for part 39 continues to read as follows:
**Authority:**
49 U.S.C. 106(g), 40113, 44701.
§ 39.13
**14 CFR Part 39**
2. The FAA amends § 39.13 by:
a. Removing Airworthiness Directive 2021-22-12, Amendment 39-21785 (86 FR 60753, November 4, 2021); and
b. Adding the following new airworthiness directive:
*2026-06-71 Honda Aircraft Company LLC:* Amendment 39-23293; Docket No. FAA-2025-0485; Project Identifier AD-2024-00670-A.
**(a) Effective Date**
This airworthiness directive (AD) is effective May 8, 2026.
**(b) Affected ADs**
This AD replaces AD 2021-22-12, Amendment 39-21785 (86 FR 60753, November 4, 2021) (AD 2021-22-12).
**(c) Applicability**
This AD applies to the following Honda Aircraft Company LLC Model HA-420 airplanes, certificated in any category:
(1) Group 1 airplanes: serial numbers 42000153 through 42000158 and 42000160 through 42000206; and
(2) Group 2 airplanes: serial numbers 42000211, 42000212, and 42000215 through 42000287.
**(d) Subject**
Joint Aircraft System Component (JASC) Code 2752, Trailing Edge Flap Actuator.
**(e) Unsafe Condition**
This AD was prompted by a report that the flap pushrod assemblies are susceptible to corrosion. The FAA is issuing this AD to prevent failure of the flap control pushrod assembly. The unsafe condition, if not addressed, could result in uncontrolled and un-annunciated flap asymmetry with consequent loss of control of the airplane.
**(f) Compliance**
Comply with this AD within the compliance times specified, unless already done.
**(g) Retained Actions From AD 2021-22-12 for Group 1 Airplanes**
(1) Within 90 days after November 19, 2021 (the effective date of AD 2021-22-12), or 18 months after issuance of the first standard certificate of airworthiness, whichever occurs later: Remove, clean, apply corrosion inhibiting compound (CIC) to, and reinstall the left and right inboard and outboard flap control pushrod assemblies by following steps (3) through (6) of the Accomplishment Instructions in Honda Aircraft Company Alert Service Bulletin No. SB-420-27-008, dated August 31, 2021.
(2) Within 90 days or 300 hours time-in-service (TIS), whichever occurs first after accomplishing the actions required by paragraph (g)(1) of this AD, and thereafter at intervals not to exceed 90 days or 300 hours TIS, whichever occurs first: Reapply CIC by following step (5)(a) through (c) of the Accomplishment Instructions in Honda Aircraft Company Alert Service Bulletin No. SB-420-27-008, dated August 31, 2021.
**(h) New Required Actions for Group 1 and Group 2 Airplanes**
(1) Within 2 years after the effective date of this AD, replace the flap control pushrod assemblies with redesigned (zero hours TIS) flap control pushrod assemblies in accordance with steps (3) through (5) of the Accomplishment Instructions in Honda Aircraft Company Alert Service Bulletin No. SB-420-27-009 Revision B, dated August 5, 2025.
(2) For Group 1 airplanes, accomplishing the replacement required by paragraph (h)(1) of this AD terminates the requirements of paragraphs (g)(1) and (2) of this AD.
**(i) Installation Prohibition**
As of the effective date of this AD, do not install on any airplane, an inboard or outboard flap control pushrod assembly part number that is identified in the Effectivity section of Honda Aircraft Company Alert Service Bulletin No. SB-420-27-009 Revision B, dated August 5, 2025.
**(j) No Reporting Requirement**
Although Honda Aircraft Company Alert Service Bulletin No. SB-420-27-008, dated August 31, 2021, and Alert Service Bulletin No. SB-420-27-009, Revision B, dated August 5, 2025, specify to submit certain information to the manufacturer, this AD does not include those requirements.
**(k) Alternative Methods of Compliance (AMOCs)**
(1) The Manager, East Certification 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 East Certification 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.
(3) For material that contains steps that are labeled as Required for Compliance (RC), the provisions of paragraphs (k)(3)(i) and (ii) of this AD apply.
(i) The steps labeled as RC, including substeps under an RC step and any figures identified in an RC step, must be done to comply with the AD. An AMOC is required for any deviations to RC steps, including substeps and identified figures.
(ii) Steps not labeled as RC may be deviated from using accepted methods in accordance with the operator's maintenance or inspection program without obtaining approval of an AMOC, provided the RC steps, including substeps and identified figures, can still be done as specified, and the airplane can be put back in an airworthy condition.
**(l) Additional Information**
For more information about this AD, contact Kelly Fichter, Aviation Safety Engineer, FAA, 1701 Columbia Avenue, College Park, GA 30337; phone: (404) 474-5544; 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.
(3) The following material was approved for IBR on May 8, 2026.
(i) Honda Aircraft Company Alert Service Bulletin No. SB-420-27-009, Revision B, dated August 5, 2025.
(ii) [Reserved]
(4) The following material was approved for IBR on November 19, 2021 (86 FR 60753, November 4, 2021).
(i) Honda Aircraft Company Alert Service Bulletin No. SB-420-27-008, dated August 31, 2021.
(ii) [Reserved]
(5) For Honda Aircraft Company material identified in this AD, contact Honda Aircraft Company LLC, 6430 Ballinger Road, Greensboro, NC 27410; phone: (336) 662-0246; website: *hondajet.com.*
(6) 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.
(7) 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 March 20, 2026.
Steven W. Thompson,
Acting Deputy Director, Compliance & Airworthiness Division, Aircraft Certification Service.