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-2026-4630; Project Identifier MCAI-2025-01824-R” 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 David Enns, 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

European Union Aviation Safety Agency (EASA), which is the Technical Agent for the Member States of the European Union, has issued EASA AD 2025-0282, dated December 12, 2025 (EASA AD 2025-0282) (also referred to as the MCAI), to correct an unsafe condition on certain HG Model Cabri G2 helicopters. The MCAI states that a ( printed page 24753) report of a potential malfunction of the helicopter ELT was received. Subsequent investigation revealed that due to improper antenna installation (location), the ELT produced a weaker signal than expected on 121.5 MHz and 406 MHz frequencies. The MCAI further states that both HG cockpit ELT antenna configurations are affected.

The FAA is issuing this AD to address the safety risk posed by weak ELT signal transmissions. The unsafe condition, if not addressed, could impair the ability to detect a distress signal during a helicopter emergency, which could delay the arrival of rescue services and timely medical assistance to injured occupants.

You may examine the MCAI in the AD docket at regulations.gov under Docket No. FAA-2026-4630.

Material Incorporated by Reference Under 1 CFR Part 51

The FAA reviewed Guimbal Mandatory Service Bulletin SB 25-006 B, dated December 12, 2025 (Guimbal SB 25-006 B), which specifies procedures for removing the VHF2 antenna and associated parts from service (if installed), modifying the ELT antenna, which includes relocating the ELT antenna from inside the cockpit to an exterior location, relocating and installing a new VHF2 antenna (if installed), torquing nuts, installing cotter pins, trimming the cowlings, routing the ELT antenna cable, repairing the engine cowl honeycomb, and paint touch-ups.

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 and material 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 revising the limitations section of the existing RFM for the helicopter to prohibit overwater operations conducted under 14 CFR part 135, pursuant to 14 CFR 135.168. The owner/operator (pilot) holding at least a private pilot certificate may revise the existing RFM and must enter compliance into the helicopter maintenance records in accordance with 14 CFR 43.9(a) and 91.417(a)(2)(v). The pilot may perform this action because it only involves revising the RFM, which could be performed equally well by a pilot or mechanic. This is an exception to the FAA's standard maintenance regulations.

Differences Between This Proposed AD and the MCAI

The MCAI specifies updating the RFM to insert a RFM temporary revision in the limitation section, whereas this proposed AD does not.

The MCAI requires the modification of the ELT to be completed within 6 months, whereas this proposed AD does not.

Costs of Compliance

The FAA estimates that this AD, if adopted as proposed, would affect 70 helicopters of U.S. registry.

The FAA estimates the following costs to comply with this proposed AD:

The FAA estimates the following costs to do the optional modification. The agency has no way of determining the number of helicopters that might need this repair:

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 ( printed page 24754) under the criteria of the Regulatory Flexibility Act.

The Proposed Amendment

Accordingly, under the authority delegated to me by the Administrator, the FAA proposes to amend 14 CFR part 39 as follows:

1. The authority citation for part 39 continues to read as follows:

Authority: 49 U.S.C. 106(g), 40113, 44701.

2. The FAA amends § 39.13 by adding the following new airworthiness directive:

Hélicoptères Guimbal: Docket No. FAA-2026-4630; Project Identifier MCAI-2025-01824-R.

(a) Comments Due Date

The FAA must receive comments on this airworthiness directive (AD) by June 22, 2026.

(b) Affected ADs

None.

(c) Applicability

This AD applies to Hélicoptères Guimbal (HG) Model Cabri G2 helicopters having serial number (S/N) 1003 to 1389, except S/N 1383 and 1388, certificated in any category.

(d) Subject

Joint Aircraft System Component (JASC) Code 2562, Emergency Locator Beacon.

(e) Unsafe Condition

This AD was prompted by a report of a potential malfunction of the helicopter emergency locator transmitter (ELT) and subsequent findings of weak ELT signals on 121.5 MHz and 406 MHz frequencies due to improper antenna installation (location). The FAA is issuing this AD to address the safety risk posed by weak ELT signal transmissions. The unsafe condition, if not addressed, could impair the ability to detect a distress signal during a helicopter emergency, which could delay the arrival of rescue services and timely medical assistance to injured occupants.

(f) Compliance

Comply with this AD within the compliance times specified, unless already done.

(g) Required Actions

Within 30 days after the effective date of this AD, revise the limitations section of the existing rotorcraft flight manual (RFM) for the helicopter by inserting the following text “For Cabri G2 not equipped with the external ELT antenna: Operations conducted overwater under 14 CFR part 135 are prohibited pursuant to 14 CFR 135.168”.

(1) Inserting a copy of this AD into the limitation section of the RFM satisfies the requirements of paragraph (g) of this AD.

(2) For this AD, the owner/operator (pilot) holding at least a private pilot certificate may revise the existing RFM for the helicopter and must enter compliance into the helicopter maintenance records in accordance with 14 CFR 43.9(a) and 91.417(a)(2)(v). The record must be maintained as required by 14 CFR 91.417, 121.380, or 135.439.

(h) Optional Terminating Action

(1) For internal ELT antenna helicopters, modify the ELT antenna and relocate and install a new VHF2 antenna (if installed) in accordance with section 2 ELT Antenna Installation through section 4 Engine Cowl Honeycomb Repair of Guimbal Mandatory Service Bulletin SB 25-006 B, dated December 12, 2025 (Guimbal SB 25-006 B), except as provided in paragraphs (h)(1)(i) and (ii) of this AD.

(i) Instead of discarding parts, you must remove those parts from service.

(ii) Where Guimbal SB 25-006 B uses the term check, this AD requires doing an inspection.

(2) Upon completion of paragraph (h)(1) of this AD, revise the RFM by removing the limitation identified in paragraph (g) of this AD.

(i) 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 (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 David Enns, Aviation Safety Engineer, FAA, 1600 Stewart Avenue, Suite 410, Westbury, NY 11590; phone: (316) 946-4147; email: david.enns@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) Guimbal Mandatory Service Bulletin SB 25-006 B, dated December 12, 2025.

(ii) [Reserved]

(3) For Guimbal material identified in this AD, contact Hélicoptères Guimbal, 1070, rue du Lieutenant Parayre, Aérodrome d'Aix-en-Provence, 13290 Les Milles, France; phone: 33-04-42-39-10-88; email: support@guimbal.com; website: guimbal.com.

(4) You may view this material at the FAA, Airworthiness Products Section, Operational Safety Branch, 10101 Hillwood Parkway, Fort Worth, TX 76177. 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.

91 FR 24752