Narrative:

Storage preparations for the aircraft were being made while engine repairs were to take place. This included filling the fuel tanks to prevent water condensation during the period of prolonged storage. It was noted that the amount of fuel required was less than that predicted. Therefore, the amount of fuel in the airplane prior to takeoff was greater than estimated. This prompted a complete review of weight and balance calculations, which revealed the airplane to be between 70 and 90 pounds over gross takeoff weight. The cg was within limits for maximum gross takeoff weight. The apparent cause of the error in fuel estimation was due to lower than calculated fuel burn in the flight immediately proceeding. The oil leak and weight of the aircraft are not directly related events. Aircraft performance during takeoff, climb and cruise, including air speed and rate of climb, were within normal range and calculations. Engine systems monitoring including oil temperature, oil pressure, fuel flow and fuel pressure, manifold pressure, propeller RPM, and vacuum pressure were all normal prior to development of the oil leak. The finding of greater than estimated fuel reserves has prompted reevaluation and alteration of the method of determining partial filling of fuel tanks for flts near maximum gross weight. Fuel tanks will be filled completely and drained of the necessary amount of fuel to meet weight requirements, and then stored in approved containers. This will allow for the greatest accuracy in fuel calculations and weight and balance compliance.

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Original NASA ASRS Text

Title: GA SMA TKOF IN EXCESS OF MAXIMUM ALLOWABLE GROSS WEIGHT.

Narrative: STORAGE PREPARATIONS FOR THE ACFT WERE BEING MADE WHILE ENG REPAIRS WERE TO TAKE PLACE. THIS INCLUDED FILLING THE FUEL TANKS TO PREVENT WATER CONDENSATION DURING THE PERIOD OF PROLONGED STORAGE. IT WAS NOTED THAT THE AMOUNT OF FUEL REQUIRED WAS LESS THAN THAT PREDICTED. THEREFORE, THE AMOUNT OF FUEL IN THE AIRPLANE PRIOR TO TKOF WAS GREATER THAN ESTIMATED. THIS PROMPTED A COMPLETE REVIEW OF WT AND BAL CALCULATIONS, WHICH REVEALED THE AIRPLANE TO BE BTWN 70 AND 90 LBS OVER GROSS TKOF WT. THE CG WAS WITHIN LIMITS FOR MAX GROSS TKOF WT. THE APPARENT CAUSE OF THE ERROR IN FUEL ESTIMATION WAS DUE TO LOWER THAN CALCULATED FUEL BURN IN THE FLT IMMEDIATELY PROCEEDING. THE OIL LEAK AND WT OF THE ACFT ARE NOT DIRECTLY RELATED EVENTS. ACFT PERFORMANCE DURING TKOF, CLB AND CRUISE, INCLUDING AIR SPD AND RATE OF CLB, WERE WITHIN NORMAL RANGE AND CALCULATIONS. ENG SYSTEMS MONITORING INCLUDING OIL TEMP, OIL PRESSURE, FUEL FLOW AND FUEL PRESSURE, MANIFOLD PRESSURE, PROP RPM, AND VACUUM PRESSURE WERE ALL NORMAL PRIOR TO DEVELOPMENT OF THE OIL LEAK. THE FINDING OF GREATER THAN ESTIMATED FUEL RESERVES HAS PROMPTED REEVALUATION AND ALTERATION OF THE METHOD OF DETERMINING PARTIAL FILLING OF FUEL TANKS FOR FLTS NEAR MAX GROSS WT. FUEL TANKS WILL BE FILLED COMPLETELY AND DRAINED OF THE NECESSARY AMOUNT OF FUEL TO MEET WT REQUIREMENTS, AND THEN STORED IN APPROVED CONTAINERS. THIS WILL ALLOW FOR THE GREATEST ACCURACY IN FUEL CALCULATIONS AND WT AND BAL COMPLIANCE.

Data retrieved from NASA's ASRS site as of August 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.