Amateur-built CHALLENGER - II N30796 accident near Chippewa Falls, Wisconsin

Probable cause

The pilot’s incapacitation due to a cardiovascular event, which resulted in a loss of control and subsequent impact with terrain.

NTSB analysis

While the airplane was on the downwind leg of the traffic pattern at the pilot's home airport, witnesses observed it enter into a steep dive that continued to ground contact in an open field. Postaccident examination of the airframe and engine revealed no evidence of mechanical malfunctions or failures that would have precluded normal operation.

The recreational pilot's medical history included coronary artery disease treated with multivessel bypass surgery. The autopsy documented severe coronary artery disease and damage to the heart muscle; including myocarditis (inflammation of the heart muscle), which placed the pilot at severe risk of a cardiac arrhythmia (irregular heart rhythm) and incapacitation. Based on the autopsy findings and the pilot's medical history, he most likely became incapacitated due to a cardiovascular event secondary to his severe heart disease and recent myocarditis.

Text from the NTSB. Open the NTSB docket for CEN15LA195 for the full record.