As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
ON DESCENT WITH POWER APPROX 50 PERCENT, A MODERATE VIBRATION WAS FELT. WITH THRUST LEVER AT IDLE NO VIBRATION NOTE, HOWEVER, ON ACCELERATION VIBRATION INCREASED WITH LEVER MOVEMENT. REMOVED AND REPLACED NR 3 ENGINE S/N 700279. ON INSPECTION OF ENGINE FOUND EXTENSIVE DAMAGE TO THE SEVENTH STAGE AND TURBINE SECTION. INSTALLED ENGINE. (M)