Flight History
During an IFR flight at FL170, the pilot reported airframe icing and requested a higher altitude. He climbed to FL210 where he started a descent and reported a loss of manifold pressure in the left engine. The pilot indicated that weather was in his flight path and descent was required to avoid icing. Ninety seconds later, the pilot transmitted '...losing it...'. Radar data indicated the aircraft had an inflight breakup at approximately 17,000 feet MSL.
Aircraft Condition
There was no evidence of mechanical or structural malfunction prior to the breakup. The aircraft did not have a complete current annual inspection, and its de-ice equipment was inoperative.
Pilot Information
The pilot had no actual instrument experience and was not certified for multi-engine IFR flight. He had a medical history of anxiety attacks and had been taking prescription medication, Xanax and Tofranil, for approximately three years prior to the accident. Blood toxicology revealed 1.2 mcg/ml of imipramine (Tofranil) and 2.6 mcg/ml desipramine (metabolite of Tofranil). Xanax (alprazolam) was not reported in the blood toxicology. These drugs have been known to produce side effects that include poor judgment. The pilot, sole on board, was killed.
Toxicological Findings
Blood samples contained imipramine and desipramine, consistent with Tofranil use. The absence of alprazolam suggests Xanax was not present at the time. The source notes that these medications can cause side effects such as poor judgment.
Breakup and Subsequent Collision
The inflight breakup occurred during an uncontrolled descent. The aircraft subsequently collided with terrain in a residential area.
Official Findings
Probable cause (as stated in the official findings):
- Occurrence #1: In flight encounter with weather. Findings: weather condition (thunderstorm, icing conditions, rain, turbulence); flight control surfaces/attachments – ice; in-flight planning/decision – poor (pilot in command); impairment (drugs) – pilot in command; flight into known adverse weather – intentional (pilot in command); lack of total instrument time (pilot in command); operation with known deficiencies in equipment (pilot in command).
- Occurrence #2: Loss of engine power (partial) – nonmechanical. Findings: 1 engine; engine assembly – undetermined.
- Occurrence #3: Airframe/component/system failure/malfunction. Findings: operation with known deficiencies in equipment (pilot in command); design stress limits of aircraft – exceeded (pilot in command).
- Occurrence #4: In flight collision with terrain/water. Findings: terrain condition – residential area.