As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
A SLIGHT RUB WAS HEARD IN THE COMPRESSOR WHEN THE N1 WAS ROTATED. UPON CASE HALF REMOVAL FOR INSPECTION, SEVERE VANE EROSION WAS FOUND. THE CHORD OF ONE VANE WAS SO THIN AS TO CAUSE THE VANE TO BEND AND RUB ON THE COMPRESSOR ROTOR. SUBMITTER SUSPECTS CASE HALF INSPECTIONS FOR OPERATION IN AN EROSIVE ENVIRONMENT WERE NOT CARRIED OUT PER THE MM.