What happened
The pilot and his wife traveled to a remote location where she had previously spotted a caribou. After landing on a gravel bar, she successfully hunted the animal. However, she soon began experiencing severe headaches and vision problems. While the pilot loaded the meat and horns into the aircraft, her condition deteriorated.
Shortly after takeoff, at approximately 20 feet above ground level, the wife made an unusual sound. The pilot felt a strong force on the right rudder controls. He later stated that he believed she had suffered a seizure. He shouted for her to release the controls but was unable to overcome the force applied to the rudder. The aircraft lost lift and crashed onto a river bank. The wife sustained a head injury and died from her wounds. An autopsy did not confirm that she had a seizure.
The investigation
Medical examination of the pilot's wife revealed a head injury consistent with the crash impact. However, forensic analysis did not verify that she had suffered a seizure prior to the accident. The cause of her sudden medical distress remained undetermined based on available evidence.
Findings
The aircraft crashed due to the pilot's inability to maintain control after his passenger became incapacitated. Contributing factors included the passenger's unexplained medical symptoms and the resulting loss of control during the initial climb phase.