What happened
The aircraft departed from a lake surface, but shortly after liftoff, the engine ceased producing power. As the airplane began to settle toward the remaining body of water, the engine momentarily surged before failing completely. The aircraft subsequently crashed onto the adjacent tundra, coming to rest approximately 200 yards from the edge of the lake.
The investigation
During the post-accident review, the pilot provided details regarding his pre-flight procedures earlier that day. He reported that during the first flight, he drained the fuel sumps and discovered the presence of water in the fuel system. However, for the flights that followed this initial inspection, he did not drain the fuel sumps again.
Findings
The evidence indicates that water contamination in the fuel system was the primary factor leading to the loss of engine power. The pilot's decision to inspect and clear water during the first flight but neglect to perform the same procedure on subsequent flights allowed contaminants to accumulate or persist, ultimately causing the engine to stop.
Safety message
Pilots must ensure that fuel sumps are drained before every flight, regardless of whether they were drained earlier in the day. Ignoring this step can lead to critical engine failures due to water contamination.