What happened
Prior to departing for a visual flight rules (VFR) night cross-country flight, the pilot obtained three separate weather briefings. These briefings indicated that the destination area was forecast to experience heavy rain, hail, and thunderstorms.
While en route, the pilot contacted a flight service station via a flight watch frequency to request an updated weather report for the destination. During this update, the pilot was notified that while rain had moved through the destination airport area within the previous hour, thunderstorms were present northwest of the airport.
Thirteen minutes after this in-flight weather update, the aircraft disappeared from radar. Radar data indicated the airplane descended from 2,8ually800 feet to 2,300 feet before losing coverage. The final two radar returns showed the aircraft performing a turn toward the northwest. One of the surviving passengers noted that the weather conditions worsened during the flight. The aircraft eventually struck trees in hilly terrain at an elevation of approximately 1,675 feet MSL.
The investigation
The investigation found no engine or aircraft anomalies that would have interfered with normal operations. However, toxicology results for the pilot showed he was taking sertraline, an antidepressant medication. Additionally, it was determined that the FAA had not issued a medical certificate to the pilot at the time of his most recent medical application.