HEBERLEIN RONALD VANS RV 9A — Sebring, FL

What happened

The 76-year-old commercial pilot was making a personal cross-country flight in the airplane. Video from the departure airport's security camera showed the airplane taking off about 38 minutes before sunrise. Shortly thereafter, a witness 4 miles southeast of the airport reported hearing the airplane fly over at a low altitude followed by the sound of impact.

The ground scars and wreckage distribution at the accident site indicated that the airplane likely impacted terrain in a near straight-and-level attitude and at an airspeed within the normal flight envelope, suggesting that the airplane was under control at the time of impact. During examination of the airframe and engine, no anomalies were found that would have precluded normal operation of the airplane.

The pilot's autopsy revealed that he had severe coronary artery disease but no evidence of an old or new heart attack. An acute cardiac event would leave no evidence on autopsy; however, given the indications that this was controlled flight into terrain, it is unlikely that the pilot's coronary artery disease contributed to the circumstances of the accident.

The pilot's toxicology findings included two potentially-impairing sedating antihistamines, chlorpheniramine and diphenhydramine. However, due to limited specimens, blood drug levels were not available, and the investigation was unable to determine whether the sedating antihistamines or the conditions being treated by the medications contributed to the circumstances of the accident. Finally, the pilot had recently been diagnosed with early dementia of the Alzheimer's type, and the cognitive and visuospatial deficits resulting from this disease likely impaired his ability to safely control the airplane. However, the investigation was unable to determine if the cognitive impairment directly contributed to the accident.

An editorial "what led to it / how to avoid it" analysis for this accident is generated separately and will appear here.