Document ID: chunk:federal_register_of_legislation:F2008L03223:body:0:p2
Version: federal_register_of_legislation:F2008L03223
Segment Type: other
Provision Reference: 
Character Range: 2851–4278

harness connector is disconnected and reconnected.
             This Airworthiness Directive becomes effective on 29 August 2008.
Background:  An occurrence involving the disconnection of a main rotor blade de-icing harness was covered by Direction Générale de l'Aviation Civile of France (DGAC) AD
             F-2005-214, issued on 1 February 2006.  The de-icing harness connector, which is a screwed-type self-locking connector, was affected by an assembly anomaly of its retaining ring which led to the loss of the locking function.

             Since then, during a flight-related check, another connector of the main rotor blade de-icing harness was found not fully tightened on the slip-ring assembly side.  No case of failure of the connector of the same harness on the blade side has been reported so far to EASA.

             Regarding the latest case of connector disconnection, investigations revealed that the loss of the locking function is due to the failure of a self-locking spring ring inside the connector.  In the event of such a situation, the de-icing function on all main rotor blades is lost, which can be detrimental for the safety of the helicopter flying in icing conditions.

             Therefore, this Directive is issued in order to prevent untimely disconnection of the incriminated de-icing harness connector.

James Coyne
Delegate of the Civil Aviation Safety Authority

25 August 2008