Summary
We propose to adopt a new 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:
Service experience has shown that fracture of the timing chain has occurred due to chain wear. This condition, if not corrected, could lead to in-flight cases of engine shutdown.
We are proposing this AD to prevent engine in-flight shutdown leading to loss of control of the airplane by requiring life limits for the timing chain.