Narrative:

I was sitting level at 12000 MSL on the autoplt just running in the tops of a shallow cloud layer with about 1/2 inch of mixed ice on the airframe from the climb through the overcast at akr when the left engine began to lose power and surge violently back and forth to full power. Of course I was sitting there in the middle of the night after a long day of flying and was really caught by surprise. I unhooked the autoplt and the aircraft was severely out of trim and I frankly was out of control for a period of time trying to get the airplane under control and isolate the problems. The time I spent recovering resulted in my climbing to around 13200 ft and I advised the center I had engine problems and was climbing in VFR conditions. She came back with traffic at 12 O'clock and 3 mi at 13000 MSL. I acknowledged seeing the traffic and turned to my left or southwest to better avoid the traffic. I still had not secured the violently surging engine and was trying to talk and fly and think all at the same time. Finally, the engine quit surging and ran away to maximum temperature and maximum torque and settled down. I finally shut the engine down and asked for some WX with VFR conditions at close airports. The closest VFR without the 5000 ft of overcast and ice I had been incurring all day was sbn, I asked for clearance to sbn and later within 90 mi sbn I changed my destination to mie, which was about the same distance from my present position. We landed at mie around X00 pm local time without further problems. Later, we found the fuel control had malfunctioned causing the engine to run away. I learned a good lesson that maybe a lot of turbine pilots are not really expecting is that all engine failures do not mean the engine stops but also they can run away. Interesting.

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Original NASA ASRS Text

Title: PLT OF CPR SMT ACFT DEVIATED FROM ASSIGNED ALT AND TRACK WHILE HANDLING AN INFLT ENG MALFUNCTION.

Narrative: I WAS SITTING LEVEL AT 12000 MSL ON THE AUTOPLT JUST RUNNING IN THE TOPS OF A SHALLOW CLOUD LAYER WITH ABOUT 1/2 INCH OF MIXED ICE ON THE AIRFRAME FROM THE CLB THROUGH THE OVCST AT AKR WHEN THE L ENG BEGAN TO LOSE PWR AND SURGE VIOLENTLY BACK AND FORTH TO FULL PWR. OF COURSE I WAS SITTING THERE IN THE MIDDLE OF THE NIGHT AFTER A LONG DAY OF FLYING AND WAS REALLY CAUGHT BY SURPRISE. I UNHOOKED THE AUTOPLT AND THE ACFT WAS SEVERELY OUT OF TRIM AND I FRANKLY WAS OUT OF CTL FOR A PERIOD OF TIME TRYING TO GET THE AIRPLANE UNDER CTL AND ISOLATE THE PROBS. THE TIME I SPENT RECOVERING RESULTED IN MY CLBING TO AROUND 13200 FT AND I ADVISED THE CTR I HAD ENG PROBS AND WAS CLBING IN VFR CONDITIONS. SHE CAME BACK WITH TFC AT 12 O'CLOCK AND 3 MI AT 13000 MSL. I ACKNOWLEDGED SEEING THE TFC AND TURNED TO MY L OR SW TO BETTER AVOID THE TFC. I STILL HAD NOT SECURED THE VIOLENTLY SURGING ENG AND WAS TRYING TO TALK AND FLY AND THINK ALL AT THE SAME TIME. FINALLY, THE ENG QUIT SURGING AND RAN AWAY TO MAX TEMP AND MAX TORQUE AND SETTLED DOWN. I FINALLY SHUT THE ENG DOWN AND ASKED FOR SOME WX WITH VFR CONDITIONS AT CLOSE ARPTS. THE CLOSEST VFR WITHOUT THE 5000 FT OF OVCST AND ICE I HAD BEEN INCURRING ALL DAY WAS SBN, I ASKED FOR CLRNC TO SBN AND LATER WITHIN 90 MI SBN I CHANGED MY DEST TO MIE, WHICH WAS ABOUT THE SAME DISTANCE FROM MY PRESENT POS. WE LANDED AT MIE AROUND X00 PM LCL TIME WITHOUT FURTHER PROBS. LATER, WE FOUND THE FUEL CTL HAD MALFUNCTIONED CAUSING THE ENG TO RUN AWAY. I LEARNED A GOOD LESSON THAT MAYBE A LOT OF TURBINE PLTS ARE NOT REALLY EXPECTING IS THAT ALL ENG FAILURES DO NOT MEAN THE ENG STOPS BUT ALSO THEY CAN RUN AWAY. INTERESTING.

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.