Narrative:

After a 2 hour flight from louisville, I decided to fly low over eagle creek to determine the feasibility of landing. They were reporting from unicom a crosswind of 30 mph, so I doubted we could land there. (We had just canceled IFR with ind approach.) at 150 ft, I added power for the go around, and the engine began violent power surges in excess of 500 RPM. I was using runway 21 which has only trees at the departure end, so I checked all the gauges (including power instruments) and instruments while maintaining a gradual climb. After that, I squawked 7700 and transmitted a mayday on 121.5, with no response. I planned on going straight into international (ind), which required no turns until final. However, about 1 min later, I saw a field ( I was 400 ft AGL), cut off the fuel, dumped the flaps, and turned into the wind. I landed with no problems. The aircraft and my student unharmed. I feel I could have done a few things better: open doors before landing, contact ind approach rather than 121.5. I was bothered with the fact that when I called ind approach on the ground that they seemed unaware of the problem, but they helped send the police to find me. Their primary radar was OTS, so they were using center radar (nobody saw 7700 at 400 ft AGL). Had my landing been bad, the only way emergency teams would have known of my situation would have been from local observers. The problem with the aircraft turned out to be a congregation of a filament type of substance blocking fuel to the carburetor. None of our other aircraft here at eagle creek have that problem, and I got 22 gallons in standiford field. The fact that I did sump the tanks before takeoff at standiford makes the mechanics think there might be something in the system, but the source of the blockage hasn't yet been determined.

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Original NASA ASRS Text

Title: EMER, OFF ARPT FORCED LNDG PERFORMED BY INSTRUCTOR PLT IN A C-172 AFTER EXPERIENCING FUEL STARVATION.

Narrative: AFTER A 2 HR FLT FROM LOUISVILLE, I DECIDED TO FLY LOW OVER EAGLE CREEK TO DETERMINE THE FEASIBILITY OF LNDG. THEY WERE RPTING FROM UNICOM A XWIND OF 30 MPH, SO I DOUBTED WE COULD LAND THERE. (WE HAD JUST CANCELED IFR WITH IND APCH.) AT 150 FT, I ADDED PWR FOR THE GAR, AND THE ENG BEGAN VIOLENT PWR SURGES IN EXCESS OF 500 RPM. I WAS USING RWY 21 WHICH HAS ONLY TREES AT THE DEP END, SO I CHKED ALL THE GAUGES (INCLUDING PWR INSTS) AND INSTS WHILE MAINTAINING A GRADUAL CLB. AFTER THAT, I SQUAWKED 7700 AND XMITTED A MAYDAY ON 121.5, WITH NO RESPONSE. I PLANNED ON GOING STRAIGHT INTO INTL (IND), WHICH REQUIRED NO TURNS UNTIL FINAL. HOWEVER, ABOUT 1 MIN LATER, I SAW A FIELD ( I WAS 400 FT AGL), CUT OFF THE FUEL, DUMPED THE FLAPS, AND TURNED INTO THE WIND. I LANDED WITH NO PROBS. THE ACFT AND MY STUDENT UNHARMED. I FEEL I COULD HAVE DONE A FEW THINGS BETTER: OPEN DOORS BEFORE LNDG, CONTACT IND APCH RATHER THAN 121.5. I WAS BOTHERED WITH THE FACT THAT WHEN I CALLED IND APCH ON THE GND THAT THEY SEEMED UNAWARE OF THE PROB, BUT THEY HELPED SEND THE POLICE TO FIND ME. THEIR PRIMARY RADAR WAS OTS, SO THEY WERE USING CTR RADAR (NOBODY SAW 7700 AT 400 FT AGL). HAD MY LNDG BEEN BAD, THE ONLY WAY EMER TEAMS WOULD HAVE KNOWN OF MY SIT WOULD HAVE BEEN FROM LCL OBSERVERS. THE PROB WITH THE ACFT TURNED OUT TO BE A CONGREGATION OF A FILAMENT TYPE OF SUBSTANCE BLOCKING FUEL TO THE CARB. NONE OF OUR OTHER ACFT HERE AT EAGLE CREEK HAVE THAT PROB, AND I GOT 22 GALLONS IN STANDIFORD FIELD. THE FACT THAT I DID SUMP THE TANKS BEFORE TKOF AT STANDIFORD MAKES THE MECHS THINK THERE MIGHT BE SOMETHING IN THE SYS, BUT THE SOURCE OF THE BLOCKAGE HASN'T YET BEEN DETERMINED.

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.