AN HS125 PLT HAD AN INFLT ENG SHUTDOWN.

Narrative

AS WE WERE CLBING OUT OF ABC WE HEARD A SINGLE LOUD BANG; LIKE A COMPRESSOR STALL; AT ABOUT 14500 FT. CHKING THE ENG GAUGES; I OBSERVED NO ABNORMAL INDICATIONS; AND THERE WERE NO OTHER ABNORMAL SOUNDS OR VIBRATIONS. I THEN CONTACTED OUR DIRECTOR OF MAINT ON THE RADIO TO DISCUSS THE PROB WITH HIM. AFTER A BRIEF DISCUSSION; WE ELECTED TO CONTINUE THE FLT TO BOCA RATON; DO FURTHER CHKS THERE; AND DISCUSS FURTHER WHAT WE FOUND. DURING OUR DSCNT AND APCH TO XYZ AND WHILE THE ENGS WERE RUNNING AT IDLE PWR ON THE GND; I NOTICED A SLIGHT VIBRATION COMING FROM THE L ENG. AFTER OUR ARR WE INSPECTED THE ENG FANS AND REAR TURBINE BLADES FOR DAMAGE. FINDING NO DAMAGE; WE THEN RESTARTED THE ENGS AND RAN THEM UP TO TKOF PWR TO CHK FOR ANY ABNORMALITIES. AT HIGH PWR SETTINGS THERE WERE NO ABNORMAL SOUNDS OR VIBRATIONS AND ALL ENG GAUGES GAVE NORMAL INDICATIONS. OUR DIRECTOR OF MAINT CONTACTED AN ENG FACILITY FOR FURTHER ADVICE AND ASSISTANCE. AFTER DISCUSSING THE SIT; IT WAS DETERMINED THAT THE ENG SHOULD BE SAFE FOR THE RETURN FLT TO ABC. THE RETURN FLT TO ABC WAS UNEVENTFUL UNTIL THE PWR WAS REDUCED FOR DSCNT. AT THIS POINT THE L ENG BEGAN TO VIBRATE STRONGLY AND THE ITT INCREASED TO 935 DEGS C. (THE UPPER LIMIT IS 907 DEGS C.) I THEN PULLED THE PWR LEVER TO IDLE. THE ITT DECREASED TO ABOUT 855 DEGS C AND THE VIBRATIONS CONTINUED. I THEN SHUT THE ENG DOWN USING THE APPROPRIATE CHKLIST; DECLARED AN EMER WITH ZZZ CTR; AND BRIEFED OUR PAX ON OUR SIT. WE COMPLETED A SINGLE ENG APCH AND LNDG AT ABC WITH NO FURTHER PROBS.