On March 13, 1994, a Cessna 185 (registration N4732E) operated by Mcmahon, Bob D. was involved in an aviation accident near Fort Lewis, WA. Investigators recorded the probable cause as: The pilot's loss of available power due to a seized fuel shutoff valve that restricted fuel flow. This summary draws on records from the U.S. National Transportation Safety Board (NTSB) historical archive.
A Cessna amphibious aircraft returned to the water after takeoff when available power was lost. Investigation revealed a seized fuel shutoff valve restricted fuel flow.
What happened
Shortly after departing from a lake, the pilot of a Cessna amphibian experienced an unexpected loss of available power. In response to the engine performance issue, the pilot attempted to return to the water from which he had originally taken off for a landing.
The investigation
A post-crash inspection of the aircraft was conducted to determine the mechanical cause of the failure. The examination revealed that the fuel shutoff valve was seized in a partially restricted position. This mechanical condition effectively restricted fuel flow to the engine, leading to the power loss experienced during flight.
Findings
The primary factor contributing to this incident was the mechanical failure of the fuel system. The seizure of the fuel shutoff valve prevented adequate fuel delivery, which directly resulted in the inability to maintain power during the initial climb phase.
Probable cause
The pilot's loss of available power due to a seized fuel shutoff valve that restricted fuel flow.