Accident Overview
The pilot of a single-engine aircraft departed on a Visual Flight Rules (VFR) flight but did not return to the departure airport. The wreckage of the airplane was located the following day.
Examination Findings
During a thorough post-accident examination of the airframe, flight controls, engine assembly, and related accessories, investigators found no evidence of any precrash failure or malfunction. The aircraft's systems appeared to have been operational at the time of the accident.
Pilot Medical History
The investigation revealed that the pilot had been admitted to a local hospital two days before the accident. The admitting diagnosis was gastroenteritis. The illness resulted in dehydration, a disrupted sleep pattern, and inadequate nutrition.
Medication
A prescription for the drug Phenergan (promethazine) was issued to the pilot. Promethazine is known to produce side effects of drowsiness.
Toxicology Results
Toxicology tests on the pilot's blood showed the presence of 0.034 mcg/ml of promethazine. Promethazine was also detected in the pilot's urine. The drug's sedative properties are well documented.