Summary
We propose to revise an existing airworthiness directive (AD) for the products listed above. This proposed AD results from mandatory continuing airworthiness information (MCAI) issued by an aviation authority of another country to identify and correct an unsafe condition on an aviation product. The MCAI describes the unsafe condition as: Since issuance of AD 2007-0109, Turbom[eacute]ca has released modification TU166 which consists in inserting HP blade dampers between the HP disc and the HP blade platform. Introduction of these dampers has demonstrated to limit axial displacement of the HP blade relative to the disk in case of blade lock rupture or opening, therefore eliminating the need for inspection and replacement. We are proposing this AD to prevent an uncommanded in-flight engine shutdown which could result in an emergency autorotation landing or an accident.