NTSB Identification: SEA04FA173.
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Accident occurred Sunday, August 29, 2004 in Kalispell, MT
Probable Cause Approval Date: 10/27/2005
Aircraft: Beech C35, registration: N63AC
Injuries: 2 Fatal.
NTSB investigators either traveled in support of this investigation or conducted a significant amount of investigative work without any travel, and used data obtained from various sources to prepare this aircraft accident report.
The 1,323 hour private pilot had successfully passed a biennial flight review approximately one hour before the accident. The flight instructor who administered the check flight quizzed the pilot for more than two hours before the flight, emphasizing the importance of his knowledge of the fuel system. After preflighting the airplane and visually checking that the left main fuel tank was full and the right main tank was nearly full, the instructor and the pilot departed on the check flight with the fuel selector in the "Left Hand Tank" position. After the 1.2 hour check flight was completed satisfactorily, the instructor further quizzed the pilot, culminating with the instructor advising the pilot to check his fuel before departing on a local flight for the purpose of making multiple touch and go takeoffs and landings. There was no record to indicate that the pilot had refueled prior to the accident flight. While in the traffic pattern turning from downwind to base leg witnesses heard the engine emit a loud bang, sputter, hesitate, and then go silent before banking left and going straight down. A postaccident examination revealed that the left main fuel tank, right tip tank, and center tank were intact, while the right main fuel tank and left tip tank were breached. The aircraft was leveled and approximately 5 gallons of fuel was drained from the left main tank, 2 gallons drained from the right tip tank, and 1 gallon drained from the center tank. The fuel selector handle, which was placarded, was found half way between the "OFF" position and the "Right Hand Tank" position. The fuel screen was removed and found to be clean. The fuel gage indicator selector was in the #2, "Left Hand Tank" position. The airplane's fuel system consisted of two 20 gallon main tanks in each wing, 17 usable in each tank, and one 10 gallon auxiliary tank and two 15 gallon wing tip tanks, all of which was usable. There were no records to indicate when the airplane was last refueled prior to the instructional flight. Manufacturer instructions state that when operating the fuel selector, the pilot must feel for the detent position. A FAA airworthiness directive issued in 1999 as a result of reports of engine stoppage due to the incorrect positioning of the fuel selector, was rescinded in 2000. The airworthiness directive required installing a placard on the fuel tank selector to warn of the no-flow condition that exists between the fuel tank detents. Examination of the airframe and engine did not reveal any anomalies that would preclude operation prior to the accident.
The National Transportation Safety Board determines the probable cause(s) of this accident to be: The pilot's improper positioning of the fuel tank selector, which resulted in fuel starvation and a subsequent loss of engine power while maneuvering. Full narrative available
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