What was found
SHORTLY AFTER TAKEOFF, THE CREW HEARD A LOUD BANG AND FELT A SEVERE VIBRATION, THE ENGINE INDICATION AND CREW ALERTING SYS (EICAS) DISPLAYED THE NR 2 ENGINE INTER TURBINE TEMP (ITT) AT 960C AND THE N2 CORE VIBRATION AMBER MESSAGE. THE CREW SHUTDOWN THE NR 2 ENGINE, DECLARED AN EMERGENCY AND LANDED WITHOUT FURTHER INCIDENT. BOROSCOPE INSPECTION REVEALED SEVERE DAMAGE TO SOME OF THE COMPRESSOR 5TH STAGE BLADES. THE ENGINE WAS REPLACED AND THE ACFT RETURNED INTO SERVICE. THE COMPRESSOR SPOOL STAGE 3-8 IS DISCARDED AT 22000 CYCLES.