Narrative:

I was ferrying this aircraft. I did not have very many hours in type and zero hours on this particular aircraft. I performed a very detailed preflight before departure. I found both fuel tanks to be full. I was told the fuel burn would be 7.5 to 8.5 gph. Using those numbers; I calculated a 4 - 4.5 fuel burn; to empty. At 3 hours flight time I had engine failure. I had been using my watch and an onboard timer to keep track of my time en route and to periodically switch tanks. I also was watching the sight gauges on the inside of the cabin. At the time of the occurrence my left tank (the one I was feeding from) indicated 3/4 - 1/2. The right tank indicated 1/2 - 1/4. I also found that I had to lean out the mixture almost to the point of cutoff for the engine to perform best. When the engine quit; I immediately turned right; towards ZZZ airport; informed ZZZ1 approach that I needed to land as soon as possible. I switched to the right tank and the motor did not restart. I tried the mixture. I pumped the throttle; even tried to prime -- nothing. I informed ATC that I was not going to make the airport and I then picked out a suitable dirt road to land on. My landing was uneventful; meaning it went smoothly. I was uninjured and the aircraft was not damaged. Upon inspection by the FAA and a mechanic; fuel was not present in the left tank and possibly 1 or 2 gallons in the right tank. The low sump and carburetor fuel bowl had fuel; the airplane started and ran fine prior to putting any fuel in the tank. Both glass fuel gauges showed 'empty.' the mechanic cleared the aircraft to fly. The FAA inspector 'released' me and we placed 5 gallons in each tank; I flew the aircraft off of the dirt road to ZZZ and parked for the night. The next day after the mechanics finished all necessary checks I continued on the journey. I found the fuel burn to be quite excessive -- not 8.5 gph but more close to 13 gph. I was to fly only 45 more mins on that leg before I had to land. My following legs were all limited to 2 hours; so I could monitor fuel burn. I used 9.8 - 12.2 - 8.7 - 7.6 gph on the following legs. I have not yet found the gph for my final leg. The aircraft performed well for the whole trip after the incident. Upon doing some investigations myself; I believe the airplane burned more fuel than advertised during my first leg. I thought I had 1 - 1 1/2 hours fuel left on board. I have been told that the PA-12 must be level in-flight when low on fuel for the fuel to be picked up when switched from tank-to-tank. I know both tanks were full when I left and I also do not believe any fuel vented or leaked out in-flight. In the future; I must make short first leg second leg in aircraft with unreliable fuel gauges. First legs that are as close to 1 hour so I can better judge actual fuel burn; not to just take owner's words for what the engine burns. I have always flown daytime VFR when ferrying any aircraft due to problems that can arise from any unfamiliarities or malfunctions and I plan on adhering to this policy in the future. Also maintaining strict fuel management procedures.

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Original NASA ASRS Text

Title: PA12 ON FERRY FLT SUFFERED FUEL STARVATION. PLT AND PLANE UNHARMED AFTER LNDG ON DIRT ROAD.

Narrative: I WAS FERRYING THIS ACFT. I DID NOT HAVE VERY MANY HRS IN TYPE AND ZERO HRS ON THIS PARTICULAR ACFT. I PERFORMED A VERY DETAILED PREFLT BEFORE DEP. I FOUND BOTH FUEL TANKS TO BE FULL. I WAS TOLD THE FUEL BURN WOULD BE 7.5 TO 8.5 GPH. USING THOSE NUMBERS; I CALCULATED A 4 - 4.5 FUEL BURN; TO EMPTY. AT 3 HRS FLT TIME I HAD ENG FAILURE. I HAD BEEN USING MY WATCH AND AN ONBOARD TIMER TO KEEP TRACK OF MY TIME ENRTE AND TO PERIODICALLY SWITCH TANKS. I ALSO WAS WATCHING THE SIGHT GAUGES ON THE INSIDE OF THE CABIN. AT THE TIME OF THE OCCURRENCE MY L TANK (THE ONE I WAS FEEDING FROM) INDICATED 3/4 - 1/2. THE R TANK INDICATED 1/2 - 1/4. I ALSO FOUND THAT I HAD TO LEAN OUT THE MIXTURE ALMOST TO THE POINT OF CUTOFF FOR THE ENG TO PERFORM BEST. WHEN THE ENG QUIT; I IMMEDIATELY TURNED R; TOWARDS ZZZ ARPT; INFORMED ZZZ1 APCH THAT I NEEDED TO LAND ASAP. I SWITCHED TO THE R TANK AND THE MOTOR DID NOT RESTART. I TRIED THE MIXTURE. I PUMPED THE THROTTLE; EVEN TRIED TO PRIME -- NOTHING. I INFORMED ATC THAT I WAS NOT GOING TO MAKE THE ARPT AND I THEN PICKED OUT A SUITABLE DIRT ROAD TO LAND ON. MY LNDG WAS UNEVENTFUL; MEANING IT WENT SMOOTHLY. I WAS UNINJURED AND THE ACFT WAS NOT DAMAGED. UPON INSPECTION BY THE FAA AND A MECH; FUEL WAS NOT PRESENT IN THE L TANK AND POSSIBLY 1 OR 2 GALLONS IN THE R TANK. THE LOW SUMP AND CARB FUEL BOWL HAD FUEL; THE AIRPLANE STARTED AND RAN FINE PRIOR TO PUTTING ANY FUEL IN THE TANK. BOTH GLASS FUEL GAUGES SHOWED 'EMPTY.' THE MECH CLRED THE ACFT TO FLY. THE FAA INSPECTOR 'RELEASED' ME AND WE PLACED 5 GALLONS IN EACH TANK; I FLEW THE ACFT OFF OF THE DIRT ROAD TO ZZZ AND PARKED FOR THE NIGHT. THE NEXT DAY AFTER THE MECHS FINISHED ALL NECESSARY CHKS I CONTINUED ON THE JOURNEY. I FOUND THE FUEL BURN TO BE QUITE EXCESSIVE -- NOT 8.5 GPH BUT MORE CLOSE TO 13 GPH. I WAS TO FLY ONLY 45 MORE MINS ON THAT LEG BEFORE I HAD TO LAND. MY FOLLOWING LEGS WERE ALL LIMITED TO 2 HRS; SO I COULD MONITOR FUEL BURN. I USED 9.8 - 12.2 - 8.7 - 7.6 GPH ON THE FOLLOWING LEGS. I HAVE NOT YET FOUND THE GPH FOR MY FINAL LEG. THE ACFT PERFORMED WELL FOR THE WHOLE TRIP AFTER THE INCIDENT. UPON DOING SOME INVESTIGATIONS MYSELF; I BELIEVE THE AIRPLANE BURNED MORE FUEL THAN ADVERTISED DURING MY FIRST LEG. I THOUGHT I HAD 1 - 1 1/2 HRS FUEL LEFT ON BOARD. I HAVE BEEN TOLD THAT THE PA-12 MUST BE LEVEL INFLT WHEN LOW ON FUEL FOR THE FUEL TO BE PICKED UP WHEN SWITCHED FROM TANK-TO-TANK. I KNOW BOTH TANKS WERE FULL WHEN I LEFT AND I ALSO DO NOT BELIEVE ANY FUEL VENTED OR LEAKED OUT INFLT. IN THE FUTURE; I MUST MAKE SHORT FIRST LEG SECOND LEG IN ACFT WITH UNRELIABLE FUEL GAUGES. FIRST LEGS THAT ARE AS CLOSE TO 1 HR SO I CAN BETTER JUDGE ACTUAL FUEL BURN; NOT TO JUST TAKE OWNER'S WORDS FOR WHAT THE ENG BURNS. I HAVE ALWAYS FLOWN DAYTIME VFR WHEN FERRYING ANY ACFT DUE TO PROBS THAT CAN ARISE FROM ANY UNFAMILIARITIES OR MALFUNCTIONS AND I PLAN ON ADHERING TO THIS POLICY IN THE FUTURE. ALSO MAINTAINING STRICT FUEL MGMNT PROCS.

Data retrieved from NASA's ASRS site as of January 2009 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.