Narrative:

The pawnee towplane had been down for several months for an engine major. This was to be my first flight in this airplane in 4 months. I arrived at the airport expecting to find the fuel tank full. I was a bit surprised to find the fuel down about 4-5 inches. There was a little gas on the gascolator and a stain on the floor. I assumed some had leaked out. I did a thorough preflight. I drained and checked the gascolator several times, no leaks. I have seen 3.8 hours endurance demonstrated on the towplane. I have also seen the fuel sloshing near the bottom of the tank when I have filled it, so I have a very good idea how deep the fuel tank is. I estimated that I had 3/4 fuel, or a little less than 3 hours endurance. My flight plan was for 130 SM in severe clear and low velocity winds. With an easy 1.5 hour flight ahead and almost twice that much fuel on board, I was quite comfortable. After takeoff, it was obvious that visibility in the lower levels was not as forecast, so I climbed up to on top of the haze layer, 6500 ft MSL. Flight visibility was better but navigation was difficult because of the haze layer. It didn't help matters at all that I was using a government chart instead of a sectional. I noticed that the fuel level indicator (float type), was a little lower than I expected so I planned to land at an intermediate airport to top off at about the 2/3 point of the flight. I couldn't find the airport in the haze, and meandered a bit looking for it. The fuel float was still 'bobbing' comfortably, and I didn't have that far to go, so I wasn't overly concerned. After all, I had plenty of fuel when I took off. About 20 mins from my destination airport (mmi), I began a gradual 200 FPM descent. During that descent I flew by the gliderport and contacted the glider and ground crew by radio and told them that I was going straight to my destination for fuel and would be right back. (Fuel was not available at the gliderport that day.) I had my destination airport in sight and had called on the CTAF for an airport advisory and received one. I turned directlytoward the airport. Within a few seconds, the engine quit. I quickly advanced the mixture -- no response. I then went to full throttle and got a little burst of power. I called on the CTAF that I had 'lost the engine.' they quickly came back, 'say location.' 'east of etowah, changing frequency to my ground crew.' I then called my crew and told them that I was landing in a field. During this time I had slowed and trimmed the airspeed, pulled out the carburetor heat, and made a 270 degree turn and headed out toward the most landable fields, away from the airport. I deployed full flaps and made a perfect landing although the terrain was substantially hillier than I expected. There was no damage to the airplane or to property on the ground. I used about 1/2 of the field to land. After fueling, I used about 1/4 of the field for takeoff. While I was sitting in the pasture waiting for fuel, I looked in the fuel tank with my flashlight. Imagine my surprise when I realized that the tank is essentially funnel-shaped, not the oval shape that I had pictured in my mind. Human performance considerations: 1) I was overconfident in my estimate of how much fuel was in the tank. My low time in this aircraft contributed to non-familiarity with the fuel system. 2) my decision to 'push on' to my destination in spite of not finding my intermediate fuel stop also contributed heavily. It would have been 'inconvenient' to alter course to another airport not along my route. 3) another contributing factor was being unprepared for less-than-optimum conditions for 'pilotage.' a simple GPS or even a sectional could have cut several mins off my flight time. Callback conversation with reporter revealed the following information: reporter states the FAA has not been involved in this incident. His flying club, however, has held a safety meeting and he has been put on 6 months probation from flying cross country. Reporter takes full blame for the incident and says it was pure complacency. The safety meeting consisted of a trip to the airport for all and investigating the fuel tank of the pawnee,which turns out to be conical in shape and not linear as most tanks are. That is why it appears to have several feet of depth and he believed it to have more fuel than it did. This was a lesson for all club members. Reporter has since learned that most agricultural pilots have a pretty strict rule that you fly for 2 hours and refuel no matter how much fuel appears to be left. Pretty good procedure.

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Original NASA ASRS Text

Title: PIPER PAWNEE PLT RUNS OUT OF FUEL AND MAKES OFF ARPT LNDG. NO DAMAGE, NO INJURY. PLT LOW TIME AND NON-FAMILIARITY WITH ACFT CONTRIBUTED TO INCIDENT.

Narrative: THE PAWNEE TOWPLANE HAD BEEN DOWN FOR SEVERAL MONTHS FOR AN ENG MAJOR. THIS WAS TO BE MY FIRST FLT IN THIS AIRPLANE IN 4 MONTHS. I ARRIVED AT THE ARPT EXPECTING TO FIND THE FUEL TANK FULL. I WAS A BIT SURPRISED TO FIND THE FUEL DOWN ABOUT 4-5 INCHES. THERE WAS A LITTLE GAS ON THE GASCOLATOR AND A STAIN ON THE FLOOR. I ASSUMED SOME HAD LEAKED OUT. I DID A THOROUGH PREFLT. I DRAINED AND CHKED THE GASCOLATOR SEVERAL TIMES, NO LEAKS. I HAVE SEEN 3.8 HRS ENDURANCE DEMONSTRATED ON THE TOWPLANE. I HAVE ALSO SEEN THE FUEL SLOSHING NEAR THE BOTTOM OF THE TANK WHEN I HAVE FILLED IT, SO I HAVE A VERY GOOD IDEA HOW DEEP THE FUEL TANK IS. I ESTIMATED THAT I HAD 3/4 FUEL, OR A LITTLE LESS THAN 3 HRS ENDURANCE. MY FLT PLAN WAS FOR 130 SM IN SEVERE CLR AND LOW VELOCITY WINDS. WITH AN EASY 1.5 HR FLT AHEAD AND ALMOST TWICE THAT MUCH FUEL ON BOARD, I WAS QUITE COMFORTABLE. AFTER TKOF, IT WAS OBVIOUS THAT VISIBILITY IN THE LOWER LEVELS WAS NOT AS FORECAST, SO I CLBED UP TO ON TOP OF THE HAZE LAYER, 6500 FT MSL. FLT VISIBILITY WAS BETTER BUT NAVIGATION WAS DIFFICULT BECAUSE OF THE HAZE LAYER. IT DIDN'T HELP MATTERS AT ALL THAT I WAS USING A GOV CHART INSTEAD OF A SECTIONAL. I NOTICED THAT THE FUEL LEVEL INDICATOR (FLOAT TYPE), WAS A LITTLE LOWER THAN I EXPECTED SO I PLANNED TO LAND AT AN INTERMEDIATE ARPT TO TOP OFF AT ABOUT THE 2/3 POINT OF THE FLT. I COULDN'T FIND THE ARPT IN THE HAZE, AND MEANDERED A BIT LOOKING FOR IT. THE FUEL FLOAT WAS STILL 'BOBBING' COMFORTABLY, AND I DIDN'T HAVE THAT FAR TO GO, SO I WASN'T OVERLY CONCERNED. AFTER ALL, I HAD PLENTY OF FUEL WHEN I TOOK OFF. ABOUT 20 MINS FROM MY DEST ARPT (MMI), I BEGAN A GRADUAL 200 FPM DSCNT. DURING THAT DSCNT I FLEW BY THE GLIDERPORT AND CONTACTED THE GLIDER AND GND CREW BY RADIO AND TOLD THEM THAT I WAS GOING STRAIGHT TO MY DEST FOR FUEL AND WOULD BE RIGHT BACK. (FUEL WAS NOT AVAILABLE AT THE GLIDERPORT THAT DAY.) I HAD MY DEST ARPT IN SIGHT AND HAD CALLED ON THE CTAF FOR AN ARPT ADVISORY AND RECEIVED ONE. I TURNED DIRECTLYTOWARD THE ARPT. WITHIN A FEW SECONDS, THE ENG QUIT. I QUICKLY ADVANCED THE MIXTURE -- NO RESPONSE. I THEN WENT TO FULL THROTTLE AND GOT A LITTLE BURST OF PWR. I CALLED ON THE CTAF THAT I HAD 'LOST THE ENG.' THEY QUICKLY CAME BACK, 'SAY LOCATION.' 'E OF ETOWAH, CHANGING FREQ TO MY GND CREW.' I THEN CALLED MY CREW AND TOLD THEM THAT I WAS LNDG IN A FIELD. DURING THIS TIME I HAD SLOWED AND TRIMMED THE AIRSPD, PULLED OUT THE CARB HEAT, AND MADE A 270 DEG TURN AND HEADED OUT TOWARD THE MOST LANDABLE FIELDS, AWAY FROM THE ARPT. I DEPLOYED FULL FLAPS AND MADE A PERFECT LNDG ALTHOUGH THE TERRAIN WAS SUBSTANTIALLY HILLIER THAN I EXPECTED. THERE WAS NO DAMAGE TO THE AIRPLANE OR TO PROPERTY ON THE GND. I USED ABOUT 1/2 OF THE FIELD TO LAND. AFTER FUELING, I USED ABOUT 1/4 OF THE FIELD FOR TKOF. WHILE I WAS SITTING IN THE PASTURE WAITING FOR FUEL, I LOOKED IN THE FUEL TANK WITH MY FLASHLIGHT. IMAGINE MY SURPRISE WHEN I REALIZED THAT THE TANK IS ESSENTIALLY FUNNEL-SHAPED, NOT THE OVAL SHAPE THAT I HAD PICTURED IN MY MIND. HUMAN PERFORMANCE CONSIDERATIONS: 1) I WAS OVERCONFIDENT IN MY ESTIMATE OF HOW MUCH FUEL WAS IN THE TANK. MY LOW TIME IN THIS ACFT CONTRIBUTED TO NON-FAMILIARITY WITH THE FUEL SYS. 2) MY DECISION TO 'PUSH ON' TO MY DEST IN SPITE OF NOT FINDING MY INTERMEDIATE FUEL STOP ALSO CONTRIBUTED HEAVILY. IT WOULD HAVE BEEN 'INCONVENIENT' TO ALTER COURSE TO ANOTHER ARPT NOT ALONG MY RTE. 3) ANOTHER CONTRIBUTING FACTOR WAS BEING UNPREPARED FOR LESS-THAN-OPTIMUM CONDITIONS FOR 'PILOTAGE.' A SIMPLE GPS OR EVEN A SECTIONAL COULD HAVE CUT SEVERAL MINS OFF MY FLT TIME. CALLBACK CONVERSATION WITH RPTR REVEALED THE FOLLOWING INFO: RPTR STATES THE FAA HAS NOT BEEN INVOLVED IN THIS INCIDENT. HIS FLYING CLUB, HOWEVER, HAS HELD A SAFETY MEETING AND HE HAS BEEN PUT ON 6 MONTHS PROBATION FROM FLYING XCOUNTRY. RPTR TAKES FULL BLAME FOR THE INCIDENT AND SAYS IT WAS PURE COMPLACENCY. THE SAFETY MEETING CONSISTED OF A TRIP TO THE ARPT FOR ALL AND INVESTIGATING THE FUEL TANK OF THE PAWNEE,WHICH TURNS OUT TO BE CONICAL IN SHAPE AND NOT LINEAR AS MOST TANKS ARE. THAT IS WHY IT APPEARS TO HAVE SEVERAL FEET OF DEPTH AND HE BELIEVED IT TO HAVE MORE FUEL THAN IT DID. THIS WAS A LESSON FOR ALL CLUB MEMBERS. RPTR HAS SINCE LEARNED THAT MOST AGRICULTURAL PLTS HAVE A PRETTY STRICT RULE THAT YOU FLY FOR 2 HRS AND REFUEL NO MATTER HOW MUCH FUEL APPEARS TO BE LEFT. PRETTY GOOD PROC.

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.