Narrative:

Flight diverted to bna due to suspected compressor stalls. Approaching bna at FL390 a climb to FL310 was initiated. Just as the engines achieved climb power -- the right engine EPR gauge began to fluctuate accompanied by noise and airframe vibration consistent with mild compressor stalls. A return to FL290 was initiated with throttle reduction and at the same time unloading the compressor of the right engine with engine and airfoil anti-ice. These steps immediately alleviated the stall indications. No normal or maximum parameters were exceeded the engine was operated at idle for the remainder of the flight and was shutdown after landing. Descent, approach, and landing were all normal. Note: even though an emergency was declared -- emergency authority/authorized was never used.

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Original NASA ASRS Text

Title: ACFT DIVERTS TO ALTERNATE ARPT BECAUSE OF SUSPECTED COMPRESSOR STALL IN ENG. DECLARES AN EMER BUT CLAIMS FLC NEVER USED IT.

Narrative: FLT DIVERTED TO BNA DUE TO SUSPECTED COMPRESSOR STALLS. APCHING BNA AT FL390 A CLB TO FL310 WAS INITIATED. JUST AS THE ENGS ACHIEVED CLB PWR -- THE R ENG EPR GAUGE BEGAN TO FLUCTUATE ACCOMPANIED BY NOISE AND AIRFRAME VIBRATION CONSISTENT WITH MILD COMPRESSOR STALLS. A RETURN TO FL290 WAS INITIATED WITH THROTTLE REDUCTION AND AT THE SAME TIME UNLOADING THE COMPRESSOR OF THE R ENG WITH ENG AND AIRFOIL ANTI-ICE. THESE STEPS IMMEDIATELY ALLEVIATED THE STALL INDICATIONS. NO NORMAL OR MAXIMUM PARAMETERS WERE EXCEEDED THE ENG WAS OPERATED AT IDLE FOR THE REMAINDER OF THE FLT AND WAS SHUTDOWN AFTER LNDG. DSCNT, APCH, AND LNDG WERE ALL NORMAL. NOTE: EVEN THOUGH AN EMER WAS DECLARED -- EMER AUTH WAS NEVER USED.

Data retrieved from NASA's ASRS site as of July 2007 and automatically converted to unabbreviated mixed upper/lowercase text. This report is for informational purposes with no guarantee of accuracy. See NASA's ASRS site for official report.