Summary
This document proposes the adoption of a new airworthiness directive (AD) that is applicable to Eurocopter France (Eurocopter) Model SA-365N, N1 and AS-365N2 helicopters. This proposal would require inspections of the main gearbox suspension diagonal cross-member (diagonal cross-member) for cracks, and removal of the diagonal cross- member and replacement with an airworthy diagonal cross-member if any crack is found. This proposal is prompted by several reports of the discovery of cracks in diagonal cross-members. The actions specified by the proposed AD are intended to prevent failure of the diagonal cross- member which could cause the main gearbox to pivot, resulting in severe vibrations and a subsequent forced landing.