Narrative:

Before you recommend spi for his flight test, please make sure that he has repaired the fuel gauge. If he were to supply an unairworthy aircraft for the flight test, I would be required to give him a notice of disqualification. I would not like to do that as it would seem to be merely a legal violation of the gars (91.205) and not related to safety. In fact, it could be one of the factors in a fuel exhaustion accident. The fuel gauge indicated that the left tank was about 1/8 full. Spi assured me that both tanks were, indeed, full. If the fuel cap on the right tank became loose, the slip-stream could siphon fuel from that tank and fuel would xfeed from the left to the right. At the same time, the slip-stream would hold the float in the right tank up. Now what makes me think of this, is it a vivid imagination? Not at all, it happened to me one night on a flight from northern, me to ny. I noticed that the longer we flew, the more fuel we had. I felt a little discomfort and, when the passenger said they would like to see more of the city from the air. I pleaded that I was too tired. When I refueled the next day, I learned that we would not have had enough fuel to circle the city. In our mechanic's opinion, we had a loose fuel cap and possibly a fuel vent plugged with ice. He relocated the vent behind a strut.

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Original NASA ASRS Text

Title: THE LONGER RPTR FLEW THE MORE FUEL HE SHOWED IN ONE TANK. CAP WAS LOOSE, FUEL SYPHONED OUT, SLIP STREAM HELD THE FLOAT UP AND GAVE ERRONEOUS FUEL READING.

Narrative: BEFORE YOU RECOMMEND SPI FOR HIS FLT TEST, PLEASE MAKE SURE THAT HE HAS REPAIRED THE FUEL GAUGE. IF HE WERE TO SUPPLY AN UNAIRWORTHY ACFT FOR THE FLT TEST, I WOULD BE REQUIRED TO GIVE HIM A NOTICE OF DISQUALIFICATION. I WOULD NOT LIKE TO DO THAT AS IT WOULD SEEM TO BE MERELY A LEGAL VIOLATION OF THE GARS (91.205) AND NOT RELATED TO SAFETY. IN FACT, IT COULD BE ONE OF THE FACTORS IN A FUEL EXHAUSTION ACCIDENT. THE FUEL GAUGE INDICATED THAT THE L TANK WAS ABOUT 1/8 FULL. SPI ASSURED ME THAT BOTH TANKS WERE, INDEED, FULL. IF THE FUEL CAP ON THE R TANK BECAME LOOSE, THE SLIP-STREAM COULD SIPHON FUEL FROM THAT TANK AND FUEL WOULD XFEED FROM THE L TO THE R. AT THE SAME TIME, THE SLIP-STREAM WOULD HOLD THE FLOAT IN THE R TANK UP. NOW WHAT MAKES ME THINK OF THIS, IS IT A VIVID IMAGINATION? NOT AT ALL, IT HAPPENED TO ME ONE NIGHT ON A FLT FROM NORTHERN, ME TO NY. I NOTICED THAT THE LONGER WE FLEW, THE MORE FUEL WE HAD. I FELT A LITTLE DISCOMFORT AND, WHEN THE PAX SAID THEY WOULD LIKE TO SEE MORE OF THE CITY FROM THE AIR. I PLEADED THAT I WAS TOO TIRED. WHEN I REFUELED THE NEXT DAY, I LEARNED THAT WE WOULD NOT HAVE HAD ENOUGH FUEL TO CIRCLE THE CITY. IN OUR MECH'S OPINION, WE HAD A LOOSE FUEL CAP AND POSSIBLY A FUEL VENT PLUGGED WITH ICE. HE RELOCATED THE VENT BEHIND A STRUT.

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.