Summary
This document proposes adopting a new airworthiness directive (AD) for Eurocopter France (Eurocopter) AS 350B3, SA-365N, N1, AS-365N2, AS 365N3, and EC 155B helicopters. This proposal would require modifying the SIREN cargo hook and inspecting the cargo hook locking catch (locking catch) for corrosion. This proposal is prompted by the discovery of internal corrosion on a Siren locking catch that may weaken the locking catch. The actions specified by this proposed AD are intended to detect internal corrosion of the locking catch, which can cause the locking catch to return to an incomplete locking position, undetectable by the operator, and result in an unexpected cargo load release.