Cessna 170 N2561V accident near Panama City, Florida

Probable cause

A total loss of engine power due to water contamination of the fuel, the pilot/owner's inadequate preflight inspection of his airplane, and his failure to maintain airplane control after the engine failure.

NTSB analysis

The airplane was parked outdoors for an extended period of time. The pilot/owner spent 2 days alternately draining water-contaminated fuel and test running the airplane’s engine several times. The pilot stated that he drained one fuel tank completely because the fuel appeared to be “milky” and serviced that tank with 10 gallons of fuel, but he later amended his statement and said he drained both tanks completely before he serviced them with "a combination of Jerry cans and a friend's pickup-mounted fuel tank." He then departed. The airplane experienced a total loss of engine power immediately after takeoff. The pilot attempted to return to the airport but landed in a retention pond short of the runway. The pilot reported that he performed a “shallow” turn to return to the airport, but a witness described “an abrupt/steep left-hand turn” followed by a ''stall" and descent to water contact. No preimpact mechanical anomalies were noted that would have precluded normal operation. After the accident, the engine was placed in a test cell where it started immediately, accelerated smoothly, and ran continuously without interruption. The manufacturer and the FAA have published letters, bulletins, and advisories that provided guidance to prevent accidents due to water contamination of the fuel system. It is likely that the pilot did not drain all the water-contaminated fuel from the airplane before departure, which led to the loss of engine power after takeoff.

Text from the NTSB. Open the NTSB docket for ERA12LA440 for the full record.