Narrative:

I departed hickory, nc, at approximately XA40 (VFR conditions). Because of strong turbulence, the initial altitude was 4500 ft. During the flight at cruising speed, I realized the engine was running rough. I used carburetor heat to check for carburetor icing but the engine was still running rough, with no change in performance. At approximately 9 mi from roa airport at 11500 ft, I lost significant RPM's (from 2600 to 1600 RPM's) and the engine was sounding different. I contacted roa approach explaining that I was 10 mi from roa airport, had lost RPM's and requested a full stop. WX conditions were good VFR. At 4 mi out I tested the throttle and there seemed to be no power. I did necessary emergency procedures and at approximately 1/2 mi before the airport at 2500 ft, with wind 330 degrees, 13 KTS and having to land directly into the wind, I radioed approach saying, 'I am making a left turn, I can't make it.' I headed for the valley view mall parking lot because of the good lighting. Because of having to make a sharp left turn to land at my designated spot, my left wingtip clipped a light pole. My stall buzzer went off and I dropped my nose for airspeed and headed to my landing spot, gliding all the way. Because of landing downwind, I aimed for the best stopping spot which was away from the cars and ending up against a small tree. Callback conversation with reporter revealed the following information: aircraft type C172 with a 180 engine. Reporter says cause couldn't be found and was probably carburetor ice. As RPM deteriorated the pilot headed for roa airport and contacted approach control for clearance. Airspeed deteriorated to the point reporter was getting stall warning and had to land in a parking lot which was lighted. (It was night.) on the landing he hit a curb which damaged the nosegear and the left wing hit a tree. The left wing had to be replaced. Also, during the landing his aircraft hit a parked van and knocked the mirror off, for which he was billed. Reporter says he sent $25 to the NTSB to get a copy of their report, but hasn't heard from them yet. He suspects nobody really knows what the problem was, but carburetor ice was suspected. When the engine first started running rough, he turned on the carburetor heat, but when it didn't seem to help, he turned it off. The engine progressively got rougher and RPM decreased.

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Original NASA ASRS Text

Title: WITH ROUGH RUNNING ENG RPTR APPLIED CARB HEAT, BUT APPARENTLY IT DIDN'T IMMEDIATELY IMPROVE THE ENG PROB AND RPTR PLT TURNED IT OFF. AS RPM'S CONTINUED TO DECREASE, RPTR HEADED FOR THE NEAREST ARPT, BUT COULDN'T MAKE IT AND LANDED IN A PARKING LOT. INVESTIGATED BY THE NTSB. SUSPECTED TO BE CARB ICE.

Narrative: I DEPARTED HICKORY, NC, AT APPROX XA40 (VFR CONDITIONS). BECAUSE OF STRONG TURB, THE INITIAL ALT WAS 4500 FT. DURING THE FLT AT CRUISING SPD, I REALIZED THE ENG WAS RUNNING ROUGH. I USED CARB HEAT TO CHK FOR CARB ICING BUT THE ENG WAS STILL RUNNING ROUGH, WITH NO CHANGE IN PERFORMANCE. AT APPROX 9 MI FROM ROA ARPT AT 11500 FT, I LOST SIGNIFICANT RPM'S (FROM 2600 TO 1600 RPM'S) AND THE ENG WAS SOUNDING DIFFERENT. I CONTACTED ROA APCH EXPLAINING THAT I WAS 10 MI FROM ROA ARPT, HAD LOST RPM'S AND REQUESTED A FULL STOP. WX CONDITIONS WERE GOOD VFR. AT 4 MI OUT I TESTED THE THROTTLE AND THERE SEEMED TO BE NO PWR. I DID NECESSARY EMER PROCS AND AT APPROX 1/2 MI BEFORE THE ARPT AT 2500 FT, WITH WIND 330 DEGS, 13 KTS AND HAVING TO LAND DIRECTLY INTO THE WIND, I RADIOED APCH SAYING, 'I AM MAKING A L TURN, I CAN'T MAKE IT.' I HEADED FOR THE VALLEY VIEW MALL PARKING LOT BECAUSE OF THE GOOD LIGHTING. BECAUSE OF HAVING TO MAKE A SHARP L TURN TO LAND AT MY DESIGNATED SPOT, MY L WINGTIP CLIPPED A LIGHT POLE. MY STALL BUZZER WENT OFF AND I DROPPED MY NOSE FOR AIRSPD AND HEADED TO MY LNDG SPOT, GLIDING ALL THE WAY. BECAUSE OF LNDG DOWNWIND, I AIMED FOR THE BEST STOPPING SPOT WHICH WAS AWAY FROM THE CARS AND ENDING UP AGAINST A SMALL TREE. CALLBACK CONVERSATION WITH RPTR REVEALED THE FOLLOWING INFO: ACFT TYPE C172 WITH A 180 ENG. RPTR SAYS CAUSE COULDN'T BE FOUND AND WAS PROBABLY CARB ICE. AS RPM DETERIORATED THE PLT HEADED FOR ROA ARPT AND CONTACTED APCH CTL FOR CLRNC. AIRSPD DETERIORATED TO THE POINT RPTR WAS GETTING STALL WARNING AND HAD TO LAND IN A PARKING LOT WHICH WAS LIGHTED. (IT WAS NIGHT.) ON THE LNDG HE HIT A CURB WHICH DAMAGED THE NOSEGEAR AND THE L WING HIT A TREE. THE L WING HAD TO BE REPLACED. ALSO, DURING THE LNDG HIS ACFT HIT A PARKED VAN AND KNOCKED THE MIRROR OFF, FOR WHICH HE WAS BILLED. RPTR SAYS HE SENT $25 TO THE NTSB TO GET A COPY OF THEIR RPT, BUT HASN'T HEARD FROM THEM YET. HE SUSPECTS NOBODY REALLY KNOWS WHAT THE PROB WAS, BUT CARB ICE WAS SUSPECTED. WHEN THE ENG FIRST STARTED RUNNING ROUGH, HE TURNED ON THE CARB HEAT, BUT WHEN IT DIDN'T SEEM TO HELP, HE TURNED IT OFF. THE ENG PROGRESSIVELY GOT ROUGHER AND RPM DECREASED.

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.