As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
FOLLOWING INCORPORATION OF SERVICE BULLETIN FJ44-72-127 (1ST LOW PRESSURE TURBINE NOZZLE UPGRADE) ON ENGINE, POST-MAINTENANCE VIBRATION SURVEY GROUND RUNS REVEALED N1 SPOOL VIBRATION LEVELS ABOVE LINE MAINTENANCE MANUAL LIMITS. ATTEMPTS TO TRIM-BALANCE THE ENGINE WERE UNSUCCESSFUL. SUBSEQUENT BORESCOPE INSPECTION OF THE ENGINE REVEALED DAMAGE TO 3RD-STAGE INTERMEDIATE PRESSURE COMPRESSOR (IPC) ROTOR BLADES AND ONE MISSING 3RD-STAGE BLADE. DISASSEMBLY IN THE REPAIR STATION CONFIRMED REPORT OF ONE LIBERATED 3RD-STAGE IPC ROTOR BLADE AND DAMAGE TO ADJACENT 3RD-STAGE BLADES.