Airworthiness Directives; Airbus Helicopters Deutschland GmbH (Previously Eurocopter Deutschland GmbH) (Airbus Helicopters) Helicopters

Résumé

We are adopting a new airworthiness directive (AD) for Airbus Helicopters Model MBB-BK 117 C-2 helicopters with certain duplex trim actuators installed. This AD requires repetitively inspecting the lateral and longitudinal trim actuator output levers for correct torque of the nuts. This AD was prompted by a design review that indicated the attachment screws can become loose under certain circumstances. These actions are intended to prevent the loss of an attachment screw, which could result in movement of the output lever in an axial direction, contact of a bolt connecting the control rod to an output lever with the actuator housing, and subsequent loss of helicopter control.