Bell 407 N663SF accident near Headland, Alabama

Probable cause

Pilot incapacitation by a sudden cardiac event related to severe coronary artery disease, which resulted in a loss of helicopter control.

NTSB analysis

According to the flight nurse and paramedic, the flight was normal until the helicopter suddenly rolled to the left as they approached the helipad during landing. The pilot made no attempt to correct the roll, and the helicopter rolled onto its side and the main rotors contacted the ground. The pilot was immediately observed to be unresponsive and not breathing, and the flight nurse and paramedic began CPR as quickly as they could extricate the pilot from the cockpit.

Autopsy of the pilot revealed severe coronary artery disease that placed him at significant increased risk for sudden death from an acute coronary event. Given the pilot's sudden inability to pilot the helicopter safely, the recognition by certified medical personnel that he was unresponsive and not breathing immediately following the accident, and the fact that he did not suffer enough blunt force trauma to have caused immediate cardiac arrest, it is most likely that the accident occurred because the pilot became incapacitated from an acute cardiac event.

Text from the NTSB. Open the NTSB docket for ERA20FA056 for the full record.