Pilot Debrief

Cessna A185 near Fairbanks, AK — 2018-09-27

Final reportANC18LA073
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Date
2018-09-27
Location
Fairbanks, AK, USA
Aircraft
Cessna A185
Registration
N70391
Category
Airplane
Highest injury
None
Fatalities
0
Phase of flight
Cruise

Probable cause

The total loss of engine power due to fuel exhaustion.

NTSB narrative

The pilot reported that, before departure for the 24-minute roundtrip flight, the airplane was refueled; 25 gallons of useable fuel was on board the airplane. The fuel quantity was confirmed with a custom-made fuel dipstick before departure. After landing at a lake, the pilot departed for the return flight. While in level cruise flight, at an altitude of about 1,000 ft above ground level (agl), the engine lost total power. In an effort to restore power, the pilot switched fuel tanks and activated the fuel boost pump to no avail. He performed an emergency descent to a landing on a small lake, during which the airplane impacted trees, the floats separated from the fuselage, and the airplane came to rest partially submerged with substantial damage to the wings and fuselage. Postaccident examination revealed that both left and right fuel tanks were intact; however, the fuel bladders were loose in the tank cavity with wrinkles present. About 2 gallons of fuel were recovered from the fuel tanks. The fuel line between the fuel pump and the fuel control unit was removed, and about 2 tablespoons of fluid that was light blue in color and consistent with 100LL AvGas was recovered. The fuel line between the fuel control unit and fuel manifold was removed, and no fluid was present. Examination of the engine revealed no evidence of malfunctions or anomalies. The airplane was equipped with optional long-range fuel tanks. According to the owner's manual, the total unusable fuel for an aircraft equipped with long-range fuel tanks is 6 gallons. The investigation was unable to determine if the loose fuel bladders were a result of the accident or recovery and what impact they would have had on fuel quantity and unusable fuel. However, given the lack of malfunctions or anomalies noted during the engine examination and the lack of fluid present in the fuel lines, it is likely that the engine lost power due to fuel exhaustion.

Analysis

Primary failure mode
Fuel management
First missed decision gate
Pilot could have checked fuel levels more thoroughly before departure.

NTSB coding

Evidence available

  • Photos
  • 2 docket documents
View NTSB final reportView NTSB docket

Docket documents2

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