This January 2008 accident report is provided by the National Transportation Safety Board. Published as an educational tool, it is intended to help pilots learn from the misfortunes of others.
Aircraft: Beech Bonanza. Location: Selma, Calif. Injuries: 1 Fatal. Aircraft damage: Destroyed.
What reportedly happened: The airplane was on an IFR flight plan although the weather was VFR. The pilot complied with ATC’s clearance to turn to the south-southeast in a steady 900-foot-per-minute climb. About four minutes after departure the pilot requested to leave the frequency for one minute, which the controller approved. The airplane vanished from radar four minutes later. A witness on the ground stated that he saw the airplane “disintegrate” in flight. It was determined that the airplane had entered a 5,400-foot-per-minute or greater rate of descent. The airplane wreckage was distributed along a 1,541-foot-long north-south debris field in the vicinity of the last radar return.
Examination of the wreckage did not reveal any evidence of a pre-existing airframe, engine, or flight control anomaly. The pilot had a history of episodic incapacitating pain, diabetes requiring insulin, the use of multiple potentially impairing medications, and a history of alcohol abuse. The pilot had not noted the pain, the diabetes, or the medications used to treat these conditions on his most recent application for a medical certificate.
The pilot’s FAA medical records did note a history of driving while intoxicated in 1992, but the FAA had not requested any additional details surrounding the pilot’s alcohol use. The pilot had been drinking alcohol within hours of the flight, and the forensic toxicology report was consistent with a blood alcohol level of approximately 0.07% at the time of the accident, sufficient to have resulted in impairment.
The toxicology report also was consistent with the use of multiple prescription medications that are potentially impairing, but no blood was available for evaluation and it was therefore not possible to estimate when the medications might have been most recently used or whether the pilot may have been impaired by the medication or by interactions between those medications and alcohol.
Probable cause: The pilot’s failure to maintain control, resulting in the in-flight break-up of the airplane due to aerodynamic overload. Contributing factors included the pilot’s impairment due to multiple medical conditions and recent use of alcohol.
For more information: NTSB.gov