2025-13-01: Main Rotor Blades

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: 2025-13-01 Bell Textron Canada Limited: Amendment 39-23067; Docket No. FAA-2025-1111; Project Identifier MCAI-2025-00675-R. (a) Effective Date This airworthiness directive (AD) is effective July 8, 2025. (b) Affected ADs None. (c) Applicability This AD applies to Bell Textron Canada Limited Model 407 and 427 helicopters, certificated in any category. (d) Subject Joint Aircraft System Component (JASC) Code 6210, Main Rotor Blades. (e) Unsafe Condition This AD was prompted by a report that certain expandable blade bolts installed on the main rotor blade may not have received the correct heat treatment, which could lead to stress corrosion cracking of the expandable blade bolts. The FAA is issuing this AD to prevent stress corrosion cracking of the expandable blade bolts installed on the main rotor blade. The unsafe condition, if not addressed, could result in failure of the main rotor blade assembly, detachment of the main rotor blade, and consequent loss of control of the helicopter. (f) Compliance Comply with this AD within the compliance times specified, unless already done. (g) Required Actions Within 30 hours time-in-service or 30 days, whichever occurs first after the effective date of this AD, remove from service each affected part and replace with a part eligible for installation. (h) Parts Installation Prohibition As of the effective date of this AD, do not install an affected part as defined in this AD on any helicopter. (i) Definitions For the purpose of this AD, the following definitions apply: (1) An "affected part" is an expandable blade bolt having part number (P/N) 406-310-103-103 and a serial number SLFS9386 through SLFS9405 inclusive. (2) A "part eligible for installation" is an expandable blade bolt having P/N 406-310-103-103 that does not have a serial number listed in paragraph (i)(1) of this AD. (j) 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 (k) 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. (k) Additional Information For more information about this AD, contact Adam Hein, Aviation Safety Engineer, FAA, 1600 Stewart Avenue, Suite 410, Westbury, NY 11590; phone: (316) 946-4116; email: adam.hein@faa.gov. (l) Material Incorporated by Reference None. Issued on June 17, 2025. Steven W. Thompson, Acting Deputy Director, Compliance & Airworthiness Division, Aircraft Certification Service. [FR Doc. 2025-11449 Filed 6-18-25; 11:15 am]BILLING CODE 4910-13-P