The Airworthiness Directive that the U.S. Federal Aviation Authority published today is a follow-on Airworthiness Directive from the emergency AD the FAA published on April 20.
Today’s FAA AD fully adopts the inspections recommended in CFM’s Service Bulletin issued on April 20, which EASA formerly adopted through issuance of its emergency AD on that same day.
Today’s FAA AD mandates the ultrasonic inspection and eddy current inspection of all CFM56-7B fan blades that have accumulated more than 20,000 cycles, as outlined in the CFM Service Bulletin.
These inspections are to be completed by August 31, 2018.
The AD also mandates that airlines continue to perform these inspections every 3,000 cycles (1.5 to 2 years of operation).
In addition, airlines are required to perform the inspections on fan blades as they reach the 20,000 cycle threshold, with the continued repetitive 3,000 cycle inspections.