Airworthiness Directive · Amendment 39-14510 · Eurocopter France Model SA-365N, SA-365N1, AS-365N2, and SA-366G1 Helicopters
Eurocopter France Model SA-365N, SA-365N1, AS-365N2, and SA-366G1 Helicopters
Model SA-365N, SA365N1, AS-365N2, and SA-366G1 helicopters with a main gearbox (MGB) suspension diagonal cross-member (diagonal cross-member), part number (P/N) 365A38-3023-20, -21, -22, -23, or -24, installed, certificated in any category.
This amendment supersedes an existing airworthiness directive (AD) that currently applies to Eurocopter France (ECF) Model SA 365N, N1, and AS 365N2 helicopters. That AD currently requires inspecting the main gearbox (MGB) suspension diagonal cross-member (diagonal cross-member) for cracks and replacing it with an airworthy part if any crack is found. This amendment requires more frequent inspections of the diagonal cross-member and adding the Model SA-366G1 helicopters to the applicability. This amendment is prompted by several reports of cracks in the diagonal cross-member. The actions specified by this AD are intended to prevent failure of the diagonal cross-member, pivoting of the MGB, severe vibrations, and a subsequent forced landing.
To prevent failure of the diagonal cross-member, pivoting of the MGB, severe vibrations, and subsequent forced landing, do the following:
(a) For Model SA-365N and SA-365N1 helicopters, before accumulating 15,000 operating cycles; and for Model AS-365N2 and SA-366G1 helicopters, before accumulating 11,000 operating cycles:
(1) Inspect the diagonal cross-member for a crack in the area of the center borehole. Use a borescope with a 90-degree drive, a video assembly with optical fiber illumination, or any other appropriate device that allows you to visually inspect the center area of the part.
(2) Repeat the inspection required by paragraph (a)(1) of this AD at intervals not to exceed 250 operating cycles or 50 hours time-in-service, whichever occurs first.
Note 1: “Operating cycles” are defined in the Airworthiness Limitations Section of the Master Servicing Recommendations.
(b) If a crack is found as a result of the inspections required by this AD, before further flight, replace the diagonal cross-member with an airworthy diagonal cross-member.
(c) To request a different method of compliance or a different compliance time for this AD, follow the procedures in 14 CFR 39.19. Contact the Rotorcraft Directorate, FAA, ATTN: Gary Roach, Aviation Safety Engineer, Regulations and Guidance Group, Fort Worth, Texas 76193-0111, telephone (817) 222-5130, fax (817) 222-5961, for information about previously approved alternative methods of compliance.
