Airworthiness Directives; Eurocopter France Model AS350B, B1, B2, B3, BA, C, D, D1, and AS355E, F, F1, F2, and N Helicopters

This amendment supersedes an existing airworthiness directive (AD) for the specified Eurocopter France (Eurocopter) Model AS350B, B1, B2, B3, BA, D, and AS355E helicopters, that currently requires removing certain serial-numbered main servocontrols before further flight. This amendment contains the same requirements but also requires removing certain other main and tail servocontrols on or before 550 hours time- in-service (TIS) or 24 months, whichever occurs first. Also, this amendment adds the Eurocopter Model AS350C, D1, and AS355F, F1, F2, and N helicopters to the applicability. This amendment is prompted by the discovery of a manufacturing defect in another set of servocontrols. The actions specified by this AD are intended to prevent failure of a main or tail servocontrol in the flight control system and subsequent loss of control of the helicopter.