Medical examiners are now releasing new information about a plane crash that killed two Oklahoma State University coaches and two alumni last year.
In November, 82-year-old Olin Branstetter was flying the plane when it crashed in woodsy area in Arkansas.
The ME's autopsy report shows no evidence that he suffered any medical event before the plane went down.
It also says the pilot's death was "essentially instantaneous," but examiners couldn't determine much more because of the condition of his remains.
Toxicology tests show there were no drugs in Branstetter's system at the time.
Branstetter's wife, Paula, head women's basketball coach Kurt Budke and assistant coach Miranda Serna were also killed in that crash.