Airworthiness Directives; Honda Aircraft Company LLC Airplanes
The FAA is adopting a new airworthiness directive (AD) for certain Honda Aircraft Company LLC (Honda) Model HA-420 airplanes. This AD was prompted by a report of tool damage to ...
[Docket No. FAA-2026-0020; Project Identifier AD-2025-01374-A; Amendment 39-23342; AD 2026-10-02]
RIN 2120-AA64
AGENCY:
Federal Aviation Administration (FAA), DOT.
ACTION:
Final rule.
SUMMARY:
The FAA is adopting a new airworthiness directive (AD) for certain Honda Aircraft Company LLC (Honda) Model HA-420 airplanes. This AD was prompted by a report of tool damage to multiple locations on the interior fuselage skin fiber and the omission of certain service material from the Airworthiness Limitations Section (ALS) of the maintenance manual. This AD requires incorporating certain material into the ALS of the existing maintenance manual or instructions for continued airworthiness (ICA) and the existing maintenance or inspection program, as applicable. The FAA is issuing this AD to address the unsafe condition on these products.
DATES:
This AD is effective July 2, 2026.
The Director of the Federal Register approved the incorporation by reference of a certain publication listed in this AD as of July 2, 2026.
ADDRESSES:
AD Docket:
You may examine the AD docket at
regulations.gov
under Docket No. FAA-2026-0020; 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.
( printed page 31650)
Material Incorporated by Reference:
For Honda 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, 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 atregulations.gov
under Docket No. FAA-2026-0020.
FOR FURTHER INFORMATION CONTACT:
Kelly Fichter, Aviation Safety Engineer, FAA, 1701 Columbia Avenue, College Park, GA 30337; phone: (404) 474-5544; email:
ECB-COS@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 Honda Model HA-420 airplanes. The NPRM was published in the
Federal Register
on January 22, 2026 (91 FR 2720). The NPRM was prompted by a report of tool damage to four locations on the interior fuselage skin fiber at the forward pressure bulkhead ring angle and the omission of certain service material from the ALS of the maintenance manual. The unsafe condition, if not addressed, could cause crack propagation in the skin and result in a pressurization leak and loss of pressurization.
In the NPRM, the FAA proposed to require incorporating certain material into the ALS of the existing maintenance manual or ICA and the existing maintenance or inspection program, as applicable.
Discussion of Final Airworthiness Directive
Comments
The FAA received a comment from an anonymous commenter. The commenter supported the NPRM without change.
Conclusion
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 Honda Aircraft Company Mandatory Service Bulletin SB-420-53-009, dated April 26, 2023, which specifies serial numbers of affected airplanes, compliance times, and procedures for a visual inspection for defect conditions such as impact damage, burrs, gouges, disbonding, blistering, and discoloration due to heat damage and other surface irregularities. This material also specifies procedures for an ultrasonic inspection of the fuselage skin for damage (local notches, cracks), and repair. 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 218 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
Revise the ALS
1 work-hour × $85 per hour = $85
$0
$85
$18,530
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:
(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.
This airworthiness directive (AD) is effective July 2, 2026.
(b) Affected ADs
None.
(c) Applicability
This AD applies to Honda Aircraft Company LLC (Honda) Model HA-420 airplanes, serial numbers 42000012 through 42000230, certificated in any category.
( printed page 31651)
(d) Subject
Joint Aircraft System Component (JASC) Code 5330, Fuselage Main, Plate/Skin.
(e) Unsafe Condition
This AD was prompted by a report of tool damage to multiple locations on the interior fuselage skin fiber at the forward pressure bulkhead ring angle and the omission of certain service material from the Airworthiness Limitations Section (ALS) of the maintenance manual. The FAA is issuing this AD to detect and address tool damage to the interior fuselage skin fiber at the forward pressure bulkhead ring angle. The unsafe condition, if not addressed, could cause crack propagation in the skin and result in a pressurization leak and loss of pressurization.
(f) Compliance
Comply with this AD within the compliance times specified, unless already done.
(g) Required Actions
(1) Within 30 days after the effective date of this AD, revise the ALS of the existing maintenance manual or instructions for continued airworthiness and your existing approved maintenance or inspection program, as applicable, by incorporating the information specified in Honda Aircraft Company Mandatory Service Bulletin SB-420-53-009, dated April 26, 2023.
(2) The initial compliance time for accomplishing the actions specified in Honda Aircraft Company Mandatory Service Bulletin SB-420-53-009, dated April 26, 2023, is before accumulating 6,000 total flights or within 30 days after the effective date of this AD, whichever occurs later.
(h) Provisions for Alternative Actions and Intervals
After the action required by paragraph (g) of this AD has been done, no alternative actions and associated thresholds and intervals, including life limits, are allowed unless approved as an alternative method of compliance in accordance with the procedures specified in paragraph (i)(1) of this AD.
(i) 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 (j) of this AD and email to:
AMOC@faa.gov.
(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.
(j) 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:
ECB-COS@faa.gov.
(k) 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) Honda Aircraft Company Mandatory Service Bulletin SB-420-53-009, dated April 26, 2023.
(ii) [Reserved]
(3) For Honda material identified in this AD, contact Honda Aircraft Company LLC, 6430 Ballinger Road, Greensboro, NC 27410; phone: (336) 662-0246; website:
hondajet.com.
(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.