Narrative:

We were making small deviations around the tops of some cells and were in and out of the clouds. When in the clouds we were getting pronounced st elmos fire on the windshields, but only very light turbulence. I had requested that the F/as be seated with their seat belts fastened and had actually reconfirmed that fact with them. Wing and engine anti-ice systems were on as was engine ignition. First indication of a problem was a drop in mach to aboutt .700. Normal was .760. In x-chking we noted that the engine EPR was down to about 1.2 with normal being between 1/6 and 1/8. No other lights were on indicating a problem. As the airspeed continued to bleed off I turned off the autoplt and pushed the power levers up. The first officer requested and received clearance to FL330 and I started a gradual descent. As there was still no increase in EPR I pushed the power levers up further. Sounds of compressor stall were heard in the cockpit. I retarded the power levers to idle and then increased the levers smoothly. All engine parameters returned to normal and airspeed increased. Descent was continued to FL330 and the flight continued with no other events. No damage was found upon inspection of the engines when on the ground and as of this writing the cause of the problem remains unknown.

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Original NASA ASRS Text

Title: ACR MLG FLC EXPERIENCES POWER LOSS WHILE IN CRUISE IN THE CLOUD TOPS AT FL350.

Narrative: WE WERE MAKING SMALL DEVS AROUND THE TOPS OF SOME CELLS AND WERE IN AND OUT OF THE CLOUDS. WHEN IN THE CLOUDS WE WERE GETTING PRONOUNCED ST ELMOS FIRE ON THE WINDSHIELDS, BUT ONLY VERY LIGHT TURB. I HAD REQUESTED THAT THE F/AS BE SEATED WITH THEIR SEAT BELTS FASTENED AND HAD ACTUALLY RECONFIRMED THAT FACT WITH THEM. WING AND ENG ANTI-ICE SYSTEMS WERE ON AS WAS ENG IGNITION. FIRST INDICATION OF A PROB WAS A DROP IN MACH TO ABOUTT .700. NORMAL WAS .760. IN X-CHKING WE NOTED THAT THE ENG EPR WAS DOWN TO ABOUT 1.2 WITH NORMAL BEING BTWN 1/6 AND 1/8. NO OTHER LIGHTS WERE ON INDICATING A PROB. AS THE AIRSPD CONTINUED TO BLEED OFF I TURNED OFF THE AUTOPLT AND PUSHED THE PWR LEVERS UP. THE F/O REQUESTED AND RECEIVED CLRNC TO FL330 AND I STARTED A GRADUAL DSNT. AS THERE WAS STILL NO INCREASE IN EPR I PUSHED THE PWR LEVERS UP FURTHER. SOUNDS OF COMPRESSOR STALL WERE HEARD IN THE COCKPIT. I RETARDED THE PWR LEVERS TO IDLE AND THEN INCREASED THE LEVERS SMOOTHLY. ALL ENG PARAMETERS RETURNED TO NORMAL AND AIRSPD INCREASED. DSNT WAS CONTINUED TO FL330 AND THE FLT CONTINUED WITH NO OTHER EVENTS. NO DAMAGE WAS FOUND UPON INSPECTION OF THE ENGS WHEN ON THE GND AND AS OF THIS WRITING THE CAUSE OF THE PROB REMAINS UNKNOWN.

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.