As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
ENGINE WAS RETURNED TO THE REPAIR STATION FOR A MISSING 3RD STAGE IP COMPRESSOR BLADE. ENGINE WAS RETURNED AFTER FIELD TROUBLE SHOOTING FOR AN UNUSUAL HARMONIC SOUND NOTED DURING CRUISE. DISASSEMBLY REVEALED THE 3RD STAGE IP ROTOR BLADE WAS MISSING.