What happened
During a period of maneuvering for animal tracking, the aircraft struck trees and ended up in an inverted position.
The investigation
An examination of the engine and airframe showed no mechanical malfunctions prior to the impact. All three fuel tanks contained fuel at the time of the accident. Analysis of the tree scars and propeller signatures indicated that the engine was producing power at the moment of impact.
Findings
Investigation into the pilot's toxicology report revealed the ingestion of at least three different over-the-counter medications containing sedating antihistamines. The concentration of these substances in the pilot's blood was at least five times higher than levels expected from a typical maximum single dose of such medications. The pilot's wife reported he had been suffering from a cold for approximately one week prior to the accident and had been taking NyQuil and potentially Benadryl.