Narrative:

An IFR flight from sck to wvi to sac was planned and conducted. Enough fuel was added so as to arrive sac with 1 hour 15 min as reserved (approximately 600 pounds). ATC rtings and altitude restrictions en route were cutting into these reserves but calculations showed an arrival with (500 pounds) actual fuel upon shutdown at sac was 450 pounds, well within required amounts. The big surprise was when I elected to top off all tanks to take advantage of attractive fuel prices. The amount of fuel pumped was 448 gallons with 474 usable there was only 26 gallons left (175 pounds), far below gauge indications and calculations. Time to have fuel system gauges recalibrated. No previous indications of inaccuracy. Possible water contamination of sensing probes, but aircraft had been sumped and no water found. Water in suspicion? Good thing that my personal policy is always to have at least 1 hour of reserve and not just 91.23 reserves or may have been worse.

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Original NASA ASRS Text

Title: CPR SMT PLANS FLT TO ARRIVE WITH 600 LBS OF FUEL. POST FLT INSPECTION REVEALS ONLY 175 LBS REMAINING.

Narrative: AN IFR FLT FROM SCK TO WVI TO SAC WAS PLANNED AND CONDUCTED. ENOUGH FUEL WAS ADDED SO AS TO ARRIVE SAC WITH 1 HR 15 MIN AS RESERVED (APPROX 600 LBS). ATC RTINGS AND ALT RESTRICTIONS ENRTE WERE CUTTING INTO THESE RESERVES BUT CALCULATIONS SHOWED AN ARR WITH (500 LBS) ACTUAL FUEL UPON SHUTDOWN AT SAC WAS 450 LBS, WELL WITHIN REQUIRED AMOUNTS. THE BIG SURPRISE WAS WHEN I ELECTED TO TOP OFF ALL TANKS TO TAKE ADVANTAGE OF ATTRACTIVE FUEL PRICES. THE AMOUNT OF FUEL PUMPED WAS 448 GALLONS WITH 474 USABLE THERE WAS ONLY 26 GALLONS LEFT (175 LBS), FAR BELOW GAUGE INDICATIONS AND CALCULATIONS. TIME TO HAVE FUEL SYS GAUGES RECALIBRATED. NO PREVIOUS INDICATIONS OF INACCURACY. POSSIBLE WATER CONTAMINATION OF SENSING PROBES, BUT ACFT HAD BEEN SUMPED AND NO WATER FOUND. WATER IN SUSPICION? GOOD THING THAT MY PERSONAL POLICY IS ALWAYS TO HAVE AT LEAST 1 HR OF RESERVE AND NOT JUST 91.23 RESERVES OR MAY HAVE BEEN WORSE.

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.