Accident Details
The airplane struck heavily wooded and rocky terrain after entering an uncontrolled descent from cruise climb during night visual meteorological conditions. The impact site yielded no evidence of an in-flight fire.
Toxicological Findings
Post-accident toxicological tests detected tramadol at therapeutic concentrations, along with phenobarbital, nordiazepam, chlorepheniramine, pseudoephedrine, and phenylpropanolamine. The pilot had a documented history of substance abuse. Investigators concluded it was reasonable that the pilot was impaired by the use of or withdrawal from these medications at the time of the accident.
Speed Brake Examination
Examination revealed the left wing speed brake was stowed, while the right wing speed brake was deployed. The Federal Aviation Administration reviewed flight test data from the speed brake manufacturer, which indicated no significant effect on handling qualities when one speed brake was deployed.
Maintenance Records and Mechanical Inspection
No evidence of uncorrected discrepancies was found in the maintenance records. A thorough inspection found no evidence of an in-flight mechanical or flight control malfunction that would have made the airplane uncontrollable before impact.