The FAA issued a notice of proposed rulemaking (NPRM) to amend 14 CFR part 39 by adding an AD that would apply to certain GALP Model Gulfstream G280 airplanes. The NPRM was published in the
Federal Register
on January 7, 2026 (91 FR 457). The NPRM was prompted by AD ISR I-27-2025-03-06 R1, dated August 28, 2025 (CAAI AD ISR I-27-2025-03-06 R1) (also referred to as the MCAI), issued by CAAI, which is the aviation authority for Israel. The MCAI states that several reports of empennage flight control related CAS messages have been attributed to the accumulation of water in electrical connectors located in the aft fuselage directly below the empennage. The unsafe condition, if not addressed, could, in combination with various specific failures or scenarios, result in loss of controllability of the airplane.
In the NPRM, the FAA proposed to require retrofitting the flight controls empennage electrical harness. 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-2025-5404.
The FAA received no comments on the NPRM or on the determination of the cost to the public.
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.
CAAI AD ISR I-27-2025-03-06 R1 specifies procedures for retrofitting the flight controls empennage electrical harness by replacing the backshells of electrical connectors at the vertical tail compartment.
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.
The FAA estimates that this AD affects 140 airplanes of U.S. registry. The FAA estimates the following costs to comply with this AD:
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.
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.
(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.
Accordingly, under the authority delegated to me by the Administrator, the FAA amends 14 CFR part 39 as follows:
1. The authority citation for part 39 continues to read as follows:
49 U.S.C. 106(g), 40113, 44701.
2. The FAA amends § 39.13 by adding the following new airworthiness directive:
2026-09-04 Gulfstream Aerospace LP:
Amendment 39-23325; Docket No. FAA-2025-5404; Project Identifier MCAI-2025-00424-T.
(a) Effective Date
This airworthiness directive (AD) is effective June 12, 2026.
(b) Affected ADs
None.
(c) Applicability
This AD applies to Gulfstream Aerospace LP Model Gulfstream G280 airplanes, certificated in any category, as identified in Civil Aviation Authority of Israel (CAAI) AD ISR I-27-2025-03-06 R1, dated August 28, 2025 (CAAI AD ISR I-27-2025-03-06 R1).
(d) Subject
Air Transport Association (ATA) of America Code 27, Flight Controls.
(e) Unsafe Condition
This AD was prompted by reports of the accumulation of water in electrical connectors located in the aft fuselage directly below the empennage, resulting in empennage flight control related crew alerting system (CAS) messages. The FAA is issuing this AD to address the accumulation of water in electrical connectors located in the aft fuselage directly below the empennage. The unsafe condition, if not addressed, could, in combination with various specific failures or scenarios, result in loss of controllability of the airplane.
(f) Compliance
Comply with this AD within the compliance times specified, unless already done.
(g) Requirements
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, CAAI AD ISR I-27-2025-03-06 R1.
(h) Exceptions to CAAI AD ISR I-27-2025-03-06 R1
Where CAAI AD ISR I-27-2025-03-06 R1 refers to its effective date, this AD requires using the effective date of this AD.
(i) No Reporting Requirement
Although the material referenced in CAAI AD ISR I-27-2025-03-06 R1 specifies to submit certain information to the manufacturer, this AD does not include that requirement.
(j) Additional AD Provisions
The following provisions also apply to this AD:
(1)
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 responsible Flight Standards 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 responsible Flight Standards Office.
(2)
Contacting the Manufacturer:
For any requirement in this AD to obtain instructions from a manufacturer, the instructions must be accomplished using a method approved by the Manager, International Validation Branch, FAA; or CAAI; or CAAI's authorized Designee. If approved by the CAAI Designee, the approval must include the Designee's authorized signature.
(k) Additional Information
For more information about this AD, contact Richard Bolden, Aviation Safety Engineer, FAA, 1600 Stewart Avenue, Suite 410, Westbury, NY 11590; phone: 404-474-5592; email:
richard.bolden@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 this AD specifies otherwise.
(i) Civil Aviation Authority of Israel (CAAI) AD ISR I-27-2025-03-06 R1, dated August 28, 2025.
(ii) [Reserved]
(3) For CAAI material identified in this AD, contact CAAI, P.O. Box 1101, Golan Street, Airport City, 70100, Israel; telephone 972-3-9774665; fax 972-3-9774592; email
aip@mot.gov.il.
You may find this material on the CAAI website at
www.gov.il/en/pages/israeli-airworthiness-directives.
(4) You may view this material at the FAA, Airworthiness Products Section, Operational Safety Branch, 2200 South 216th St., Des Moines, WA. For information on the availability of this material at the FAA, call 206-231-3195.
(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.