What was found
(CAN) SERVERE VIBRATION ON NR 2 ENGINE WHEN ENGINE SELECTED TO IN-FLIGHT IDLE AT TOP OF DECENT. ENGINE VIBRATION GUAGE AT FULL MAXIMUM IN "TURBINE POSITION". FLIGHT CREW PERFORMED AN INFLIGHT SHUTDOWN AND LANDED WITHOUT INCIDENT. MAINTENANCE PERSONNEL EXAMINED THE POWER TURBINE VIA THE JET PIPE AND DID NOTE TURBINE BLADE DAMAGE. ENGINE WAS REMOVED AND SENT FOR INSPECTION AND REPAIR.