SEA05FA136 · Beech E-55

According to the pilot, during his preflight inspection, he determined the fuel aboard the airplane by looking at the wing fuel sight gauges. The left and right fuel sight gauges indicated 45 gallons and 55 gallons, respectively, which was "sufficient" fuel for the planned 1 hour 50 minute cross country flight. During the flight, both engines lost power, and the pilot ditched the airplane in ocean waters about 8 nautical miles short of the destination airport. Review of maintenance records indicated that about 4 months before the accident, fuel leaks in the airplane's left and right wings were repaired by replacing the right hand outboard and left hand inboard leading edge fuel cells. This repair involved replacement of both wing fuel sight gauges. According to one of the two mechanics who performed the work, when the sight gauges were removed to replace the tanks, he and the other mechanic marked the sight gauges "R" and "L" and made hash marks on the mounting plates. When they reinstalled the sight gauges, they used the hash marks to put them back in their original positions. Interviews of the airplane's owner and another mechanic provided conflicting information about whether the fuel sight gauges had been repositioned by this mechanic following completion of the fuel cell repair work. Review of the Pilot's Operating Handbook revealed that the fuel sight gauges are to be used for partial filling or off-loading of fuel and only when the gauge reads within the calibrated area between 40 and 60 gallons. When the airplane was examined, the fuel tanks were empty. The right wing fuel sight gauge indicated 55 gallons. The left wing fuel sight gauge initially indicated in the cross hatched area; but after it was jiggled, it indicated 43 gallons. When the fuel sight gauge access plates were removed, it was noted that black felt tip pen marks (hash marks) on the fuel sight gauge mount plates and on the fuel sight gauges did not align. Further examination revealed that the gauges were installed improperly, such that the floats were restricted in their range of travel by the wing structure. When the gauges were rotated to a position where the hash marks aligned, the gauge floats had a full range of travel, and both gauges indicated in the cross hatched (unusable) area. Information provided by the airplane's owner and a trip book found in the airplane indicated that at the time the pilot conducted his preflight and at the time of the accident, the airplane had been flown 3.9 hours and 5.5 hours, respectively, since its last refueling. Using the fuel burn rate provided by the owner of 30 gallons per hour, the airplane would burn 165 gallons of fuel in 5.5 hours. Further, in the 3.9 hours flown by the owner, the airplane would burn 117 gallons. Subtracting 117 gallons from the airplane's usable fuel capacity of 166 gallons indicated that when the pilot preflighted the airplane, it contained about 49 usable gallons of fuel with each wing holding about 24.5 usable gallons of fuel. If the sight gauges had been properly installed, they would have read in the cross hatched (unusable) area. The airplane was equipped with left and right fuel quantity indicators mounted in the instrument panel. According to the owner, these indicators did not work properly and several maintenance facilities had worked on them without resolving the problem. He and other family members who flew the airplane (including the accident pilot) used the sight gauges to determine the amount of fuel aboard the airplane for partial fuel loads.

Verbatim NTSB analysis and probable cause from the NTSB dataset