Airworthiness Directive · Amendment 39-13330 · Eurocopter France Model AS 350B3, SA-365N, N1, AS-365N2, AS 365N3, and EC 155B Helicopters
Eurocopter France Model AS 350B3, SA-365N, N1, AS-365N2, AS 365N3, and EC 155B Helicopters
Model AS 350B3, SA-365N, N1, AS-365N2, AS 365N3, and EC 155B helicopters, with an optional Siren load release unit cargo hook, part number (P/N) AS-21-5-7, installed, certificated in any category.
This amendment adopts a new airworthiness directive (AD) for the specified Eurocopter France (Eurocopter) model helicopters that requires modifying the SIREN cargo hook and inspecting the cargo hook locking catch (locking catch) for corrosion. This amendment is prompted by the discovery of internal corrosion on a Siren locking catch that may weaken the locking catch. The actions specified by this 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.
