What was found
DURING CRUISE AT FL290...CREW REPORTED POP FROM RT ENG. ENG VIBE AT 5.0. FELT HEAVY VIBRATION. RETARDED THROTTLES AND STILL HAD VIBRATION. SHUTDOWN RT ENGINE. UPON ARRIVAL. FLT CREW AND CONTRACT MTC REPORTED THAT THERE WAS SIGNIFICANT DAMAGE TO THE NOSE COWL INLET AND FAN BLADES. ON FURTHER INVESTIGATION...CONTRACT MTC FOUND THAT THE FORWARD WATER SERVICE VALVE WAS PARTIALLY OPEN AND THERE WAS ICE BUILD UP WHEN THE PANEL WAS OPENED. SUSPECT ICE FROM PANEL THE CAUSE OF THE DAMAGE. NUMBER 2 ENGINE CHANGED