Narrative:

Departed ZZZ to ZZZ1, flight time 1.8 hours. Took on 12 gallons of fuel for total 4 hours fuel on board. Picked up passenger. Departed ZZZ1 for ZZZ VFR. Duats flight time was estimated 2.3 hours due to headwinds. Actual flight time was 3.1 hours due to observed headwinds of 30-40 mph (GPS). Flight was uneventful, instruments normal. Descending 6 mi out on ZZZ tower frequency at 1800 ft, engine lost power to approximately 1200 RPM. Applied full throttle and mixture and began searching for landing area. After approximately 10 seconds, engine returned to full power, instruments normal. Began climb and headed to nearest airport. Maintained full throttle and rich mixture. Approximately 4 mi from ZZZ, engine again lost power to +/-1200 RPM. Trimmed to 70 mph and located suitable road for off-airport landing. Determined could not glide to ZZZ and set up for landing on road. Engine ceased operation at base to final turn, would not start with repeated attempts. Focus was on making a safe off-airport landing. Landing was uneventful with no injuries or property damage. The next day, the engine started after 2 cranks and roughness smoothed out after 10 seconds. Ran engine for approximately 10 mins ok. Gas caps were confirmed secure and no leaks were apparent. Tank was gauged showing approximately 3/4 inch fuel. Discussed with maintenance and by their instruction added approximately 17 gallons fuel, then ran engine for 15-20 mins at various RPM and carburetor heat settings. Inspected engine visually with no apparent defects. Maintenance signed logbook as plane is airworthy. Confirmed suitable takeoff area (0.3 mi) by inspection. Discussed events with FSDO. Commercial property operator gave concurrence to take off from property. Departed property while in communication with ZZZ tower (SVFR clearance). Climbed to 700 ft and landed ZZZ, all normal. Filled tanks and confirmed better than 0.6 hour of fuel on board at time of engine power loss. Subsequent to the initial report concerning this event, a field inspection of the aircraft's fuel system found the carburetor in bad order: 'with the fuel system shutoff valve in the 'on' position, the float bowl filled and continues to vent fuel overboard.' the carburetor was replaced and the aircraft returned to service. Callback conversation with reporter revealed the following information: the reporter stated the landing was made in a cleared landfill site and no injuries and no aircraft damage. The reporter said the fuel tank was checked and found 3/8 of a tank adequate fuel on board. The reporter stated with maintenance advice, tank was filled to full by adding 17 gallons and the engine operated at various RPM for 20 mins. The reporter said after inspection and signed off as airworthy the airplane was flown 2 mi to a local airport. The reporter said an intensified inspection was made of the fuel system and the carburetor was found malfunctioning with the float valve sticking allowing the float bowl to fill and vent fuel overboard. The reporter stated the carburetor was sent to the manufacturer who did not confirm their finding but did send back a rebuilt unit. The reporter said the rebuilt carburetor was installed and has operated satisfactorily.

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Original NASA ASRS Text

Title: A CITABRIA 7ECA AT 1800 FT DECLARED AN EMER DUE TO LOSS OF ENG PWR. UNEVENTFUL OFF FIELD LNDG WAS MADE WITH NO INJURIES OR ACFT DAMAGE.

Narrative: DEPARTED ZZZ TO ZZZ1, FLT TIME 1.8 HRS. TOOK ON 12 GALLONS OF FUEL FOR TOTAL 4 HRS FUEL ON BOARD. PICKED UP PAX. DEPARTED ZZZ1 FOR ZZZ VFR. DUATS FLT TIME WAS ESTIMATED 2.3 HRS DUE TO HEADWINDS. ACTUAL FLT TIME WAS 3.1 HRS DUE TO OBSERVED HEADWINDS OF 30-40 MPH (GPS). FLT WAS UNEVENTFUL, INSTS NORMAL. DSNDING 6 MI OUT ON ZZZ TWR FREQ AT 1800 FT, ENG LOST PWR TO APPROX 1200 RPM. APPLIED FULL THROTTLE AND MIXTURE AND BEGAN SEARCHING FOR LNDG AREA. AFTER APPROX 10 SECONDS, ENG RETURNED TO FULL PWR, INSTS NORMAL. BEGAN CLB AND HEADED TO NEAREST ARPT. MAINTAINED FULL THROTTLE AND RICH MIXTURE. APPROX 4 MI FROM ZZZ, ENG AGAIN LOST PWR TO +/-1200 RPM. TRIMMED TO 70 MPH AND LOCATED SUITABLE ROAD FOR OFF-ARPT LNDG. DETERMINED COULD NOT GLIDE TO ZZZ AND SET UP FOR LNDG ON ROAD. ENG CEASED OP AT BASE TO FINAL TURN, WOULD NOT START WITH REPEATED ATTEMPTS. FOCUS WAS ON MAKING A SAFE OFF-ARPT LNDG. LNDG WAS UNEVENTFUL WITH NO INJURIES OR PROPERTY DAMAGE. THE NEXT DAY, THE ENG STARTED AFTER 2 CRANKS AND ROUGHNESS SMOOTHED OUT AFTER 10 SECONDS. RAN ENG FOR APPROX 10 MINS OK. GAS CAPS WERE CONFIRMED SECURE AND NO LEAKS WERE APPARENT. TANK WAS GAUGED SHOWING APPROX 3/4 INCH FUEL. DISCUSSED WITH MAINT AND BY THEIR INSTRUCTION ADDED APPROX 17 GALLONS FUEL, THEN RAN ENG FOR 15-20 MINS AT VARIOUS RPM AND CARB HEAT SETTINGS. INSPECTED ENG VISUALLY WITH NO APPARENT DEFECTS. MAINT SIGNED LOGBOOK AS PLANE IS AIRWORTHY. CONFIRMED SUITABLE TKOF AREA (0.3 MI) BY INSPECTION. DISCUSSED EVENTS WITH FSDO. COMMERCIAL PROPERTY OPERATOR GAVE CONCURRENCE TO TAKE OFF FROM PROPERTY. DEPARTED PROPERTY WHILE IN COM WITH ZZZ TWR (SVFR CLRNC). CLBED TO 700 FT AND LANDED ZZZ, ALL NORMAL. FILLED TANKS AND CONFIRMED BETTER THAN 0.6 HR OF FUEL ON BOARD AT TIME OF ENG PWR LOSS. SUBSEQUENT TO THE INITIAL RPT CONCERNING THIS EVENT, A FIELD INSPECTION OF THE ACFT'S FUEL SYS FOUND THE CARB IN BAD ORDER: 'WITH THE FUEL SYS SHUTOFF VALVE IN THE 'ON' POS, THE FLOAT BOWL FILLED AND CONTINUES TO VENT FUEL OVERBOARD.' THE CARB WAS REPLACED AND THE ACFT RETURNED TO SVC. CALLBACK CONVERSATION WITH RPTR REVEALED THE FOLLOWING INFO: THE RPTR STATED THE LNDG WAS MADE IN A CLRED LANDFILL SITE AND NO INJURIES AND NO ACFT DAMAGE. THE RPTR SAID THE FUEL TANK WAS CHKED AND FOUND 3/8 OF A TANK ADEQUATE FUEL ON BOARD. THE RPTR STATED WITH MAINT ADVICE, TANK WAS FILLED TO FULL BY ADDING 17 GALLONS AND THE ENG OPERATED AT VARIOUS RPM FOR 20 MINS. THE RPTR SAID AFTER INSPECTION AND SIGNED OFF AS AIRWORTHY THE AIRPLANE WAS FLOWN 2 MI TO A LCL ARPT. THE RPTR SAID AN INTENSIFIED INSPECTION WAS MADE OF THE FUEL SYS AND THE CARB WAS FOUND MALFUNCTIONING WITH THE FLOAT VALVE STICKING ALLOWING THE FLOAT BOWL TO FILL AND VENT FUEL OVERBOARD. THE RPTR STATED THE CARB WAS SENT TO THE MANUFACTURER WHO DID NOT CONFIRM THEIR FINDING BUT DID SEND BACK A REBUILT UNIT. THE RPTR SAID THE REBUILT CARB WAS INSTALLED AND HAS OPERATED SATISFACTORILY.

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.