AD 2025-18-13

This airworthiness directive (AD) is effective October 23, 2025.

This AD replaces AD 2020-24-07, Amendment 39-21337 (85 FR 78954, December 8, 2020) (AD 2020-24-07).

This AD applies to Airbus Helicopters Model AS350B3, EC130B4, and EC130T2 helicopters, certificated in any category.

Joint Aircraft System Component (JASC) Code 7600, Engine Controls.

This AD was prompted by reports of the of the engine remaining in idle when the throttle twist grip was turned from the “IDLE” mode to the “FLIGHT” mode. The FAA is issuing this AD to correct the failure of one of the microswitches, 53Ka, 53Kb, or 65K which can prevent the pilot from switching from “IDLE” mode to “FLIGHT” mode during autorotation training making it impossible to recover from a practice autorotation and compelling the pilot to continue the autorotation to the ground. This condition could result in unintended touchdown to the ground at a flight-idle power setting during a practice autorotation, damage to the helicopter, and injury to occupants.

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

Except as specified in paragraph (h) of this AD: Comply with all required actions and compliance times specified in, and in accordance with, European Union Aviation Safety Agency AD 2023-0187R1, dated March 20, 2025 (EASA AD 2023-0187R1).

(1) Where EASA AD 2023-0187R1 refers to the effective dates identified in paragraphs (h)(1)(i) through (iii) of this AD, this AD requires using the effective date of this AD.

(i) March 27, 2025 (the effective date of EASA AD 2023-0187R1).

(ii) November 10, 2023 (the effective date of EASA AD 2023-0187, dated October 27, 2023).

(iii) July 19, 2023 (the effective date of EASA AD 2023-0133, dated July 5, 2023).

(2) Where EASA AD 2023-0187R1 refers to April 13, 2017 (the effective date of EASA AD 2017-0059, dated April 6, 2017), this AD requires using January 30, 2019 (the effective date of AD 2018-26-02, Amendment 39-19532 (83 FR 66093, December 26, 2018)).

(3) Where EASA AD 2023-0187R1 refers to flight hours (FH), this AD requires using hours time-in-service.

(4) This AD does not adopt paragraphs (1) and (2) of EASA AD 2023-0187R1.

(5) Instead of complying with the compliance times in Table 1 in paragraph (3) of EASA AD 2023-0187R1, this AD requires the helicopters identified under the Helicopters in Pre-MOD 074699 Configuration column to accomplish the actions required by paragraph (3) of EASA AD 2023-0187R1 before the next practice autorotation, within 100 hours time-in-service, or 6 months after January 12, 2021 (the effective date of AD 2020-24-07), whichever occurs first.

(6) Where Table 2 in paragraph (4), Table 3 in paragraph (7), and Table 4 in paragraph (9) of EASA AD 2023-0187R1 state “For helicopters which operate or have operated in salt-laden atmospheric conditions”, this AD requires replacing that text with “For helicopters which operate or have operated in salt-laden atmospheric conditions, or if it cannot be determined if a helicopter has been operated in salt-laden atmospheric conditions”.

(7) Where paragraph (6) of EASA AD 2023-0187R1 states “discrepancies are detected”, this AD requires replacing that text with “marks, residue, corrosion, flaky varnish are detected; the values of the insulation test are less than 10 megaOhms; the microswitch closes in the “IDLE” position and does not open as soon as the twist grip is turned to the “FLIGHT” position; or the microswitch is open in the “FLIGHT” position and does not close as soon as the twist grip is turned to the “IDLE” position”.

(8) Where paragraph (9) of EASA AD 2023-0187R1 states “any discrepancy,” for purposes of this AD, discrepancy is defined as a nut torque that is outside allowable torque limits, or clearance between the support plate assembly and the washers that is not within 0.1 mm to 0.3 mm.

(9) This AD does not adopt the “Remarks” section of EASA AD 2023-0187R1.

(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.

For more information about this AD, contact Zain Jamal, Aviation Safety Engineer, FAA, 1600 Stewart Avenue, Suite 410, Westbury, NY 11590; phone: (847) 294-7264; email: zain.jamal@faa.gov.

(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) European Union Aviation Safety Agency (EASA) AD 2023-0187R1, dated March 20, 2025.

(ii) [Reserved]

(3) For EASA material identified in this AD, contact EASA, Konrad-Adenauer-Ufer 3, 50668 Cologne, Germany; phone: +49 221 8999 000; email: ADs@easa.europa.eu; website: easa.europa.eu. You may find this EASA material on the EASA website at ad.easa.europa.eu.

(4) You may view this material at the FAA, Office of the Regional Counsel, Southwest Region, 10101 Hillwood Parkway, Room 6N-321, 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.