"The last time I saw Dave alive he was relaxed and smiling," wrote Stather's friend and fellow thrill-seeker Ralph Greenaway in a post on the member site basejumper.com.
Greenaway, Stather and another companion were BASE jumping off a remote cliff in northern Arizonza near the Grand Canyon last week.
BASE stands for building, antenna, span and earth. The sport is similar to skydiving, but fans of the extreme sport launch themselves off a cliff or high building instead of jumping from a plane.
On Friday, Stather had a parachute strapped to him, as well as a wing suit.
It appears the doctor hit rocky terrain before his parachute opened just 15-20 seconds after he jumped, writes Greenaway.
Det. Pat Barr, with the Coconino County Sheriff's Office in Arizona, said Tuesday that an autopsy has been completed and the death will be ruled an accident.
Writing to announce the death to the online community, Greenaway said the trio had spoken a lot about what lines to take down the cliff. He said Stather started conservatively and got progressively lower.
He wrote that Stather's death is a "loss to everyone who knew him and everyone who now won’t get the chance to meet him."
"Sitting around our campfire the night before Dave’s death, he could not have been happier," wrote Greenaway in the post. "He talked about his life, his work and the days jumping with equal enthusiasm. It is my belief that he loved where he was in life."
Stather's body will now be transported to Guelph, Ont., where his family lives.
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