Incident Summary
During the preflight inspection of a Cessna 210, the pilot discovered water in the wing fuel tanks. However, the pilot did not drain the fuel accumulator tanks because he was unaware of their existence. Shortly after takeoff, at approximately 100 feet above ground level, the engine began to sputter and subsequently quit. The pilot was able to maneuver the aircraft and execute a landing on the airport.
Examination Findings
A post-incident examination of the aircraft's fuel system revealed extensive water contamination in both fuel tank accumulators, the engine-driven fuel pump outlet line leading to the fuel servo, and the fuel manifold inlet line. The presence of water in these components indicated that the accumulator tanks had not been drained prior to the flight.
Manual Guidance
The Cessna 210 owner's manual explicitly states that if water is found in the wing tanks, the accumulator tanks must be drained until all water is eliminated. This procedure is intended to prevent engine performance issues caused by water in the fuel system.
Aircraft Configuration
The aircraft involved was equipped with quick-removal type caps on both accumulator tanks. The extended accumulator tank drain fittings, which facilitate easier drainage, were not installed. Later models of the Cessna 210 are equipped with exterior drains for the accumulator tanks, making the drainage process more accessible during preflight inspections.