Cessna 170B N2955D accident near Curtis, Nebraska

Probable cause

Water contamination of the airplane’s fuel supply which resulted in a total loss of engine power.

NTSB analysis

The pilot reported that he took off from his private airstrip and flew for about 30 minutes before landing at a nearby airport for fuel. After fueling with 24 gallons of fuel, he did not perform a pre-takeoff run-up of the engine and departed the airport. About 1.5 miles from the airport the engine sputtered and lost all power. The pilot performed a forced landing to a small field. During the landing roll as the airplane was approaching the end of the field, the pilot applied heavy braking which caused the airplane to nose down coming to rest on it nose. The airplane sustained substantial damage to the left outboard wing.

The pilot reported that after the accident he sampled the fuel from the wing tanks and gascolator. The fuel sample from the gascolator was about one-half water and one-half fuel. The wing tank samples contained all water. The pilot provided photographs of the airport above ground fuel tank including photographs of the interior of the tank. The tank interior showed a large amount of rusted metal in the bottom of the tank.

The airport manager reported that the airport fuel tank was about 30 years old and was of double wall construction. Water had entered the space between the inner and outer walls of the tank and the inner tank had rusted by allowing water to enter the inner tank and fuel supply. The tank did not have filtering on the outlet. The airport ordered a new tank and planned to include filters on the outlet, including a water separating filter.

Text from the NTSB. Open the NTSB docket for CEN21LA206 for the full record.