What happened
Prior to takeoff, the pilot received a weather briefing and was aware that VFR conditions were not recommended. While operating on a VFR flight, the aircraft crashed in an area where the ridge tops were obscured by clouds. A witness who heard the aircraft reported that it sounded as though it had entered a steep descent before impacting the ground. An examination of the crash site confirmed that the aircraft did impact in a steep descent.
The investigation
Investigators found no evidence of any preimpact part failure or mechanical malfunction of the aircraft. However, toxicology tests performed on the pilot's liver tissue returned positive results for nordiazepam (at or above 0.148 mg/L) and maprotiline (at or above 8.6 mg/kg). Nordiazepam is a tranquilizer, and maprotiline is used in the treatment of depression. The pilot's family reported that the pilot had been prescribed Centrax (prazepam) and Ludiomil (maprotiline hydrochloride) for the control of depression.