General Aviation News will occasionally reprint excerpts or summaries of US National Transportation Safety Board (NTSB) accident reports – including this one from July 2009 about a Beech C35 crash in Weslaco, Texas that led to one death and one serious injury.
According o the accident investigation, both the Beech C35’s left and right main tanks plus the left tip tank were filled with fuel right before the aircraft departed. However and when the pilot was fueling the right tip tank, the fuel nozzle ended up falling into the tank. Hence, no fuel was added to that tank and the aircraft took off with a fuel imbalance between its tanks.
Thanks to the fuel imbalance, the aircraft had a left rolling tendency and the pilot (who was with a student pilot) headed to the nearest airfield to land so that the aircraft could be configured with 10° of flaps – contrary to the STC.
While an attempted landing, the Beech C35 bounced and drifted leftward. Hence, a go-around with a turn to the left to enter the downwind pattern was performed but during the left turn procedure, the pilot lost control of the aircraft and crashed.
The student pilot, who survived the crash, told investigators that the pilot was at the controls but investigators were not able to determine whether the flight was instructional and just who was at the controls at the time of the accident. It was also noted that:
…fracture and bending signatures on the throw-over style control column and hub were consistent with the controls being positioned toward the left seat during the accident sequence.
The NTSB ruled that the probable cause of the accident was the pilot’s failure to maintain control of the aircraft while operating with a fuel imbalance. Of course, the root cause of the accident was flying to begin with when there was a fuel imbalance.