Chris Piper's eight-storey fall landed him squarely in a club of people who, almost inconceivably, survive plunges from significant heights, experts say.
"It's not so much physics. It's luck. Very seldom would someone survive a fall of about 80 feet, which is what I figure this is close to," said University of Manitoba kinesiology and recreation professor Marion Alexander.
Piper's survival was so rare, Alexander actually sat down and calculated the odds.
And she said the odds of survival were infinitesimal.
"If you fall from 50 or 60 feet, you're likely to die. So, the fact that he survived really was just luck," Alexander said.
"He would have hit the ground at about 50 miles per hour, if he didn't hit anything," she said.
But Piper did hit something, with luck shaping up in the form of a glass ceiling panel of the apartment block solarium.
That would have cut 15 to 20 miles an hour off his velocity, Alexander said.
Piper hasn't spoken with the media yet, and it's unclear if he even recalls the miraculous landing.
But Alexander figures the position in which he landed, his age and his physical condition all added up in his favour.
"So he was lucky because he hit the glass and then he was lucky he didn't land on his head. He would have shattered his skull and likely died on the spot."
By comparison, landing on his feet, he would have broken leg bones; on his back, he would have pulverized his vertebrae; and by landing on his chest, his rib cage would have crushed his heart and other vital organs.
To drive home the lesson of human frailty, the Winnipeg professor said older people fall all the time and break their hips. "And that's a three-foot drop."
In Ottawa, the president of the Canadian Physics Association said surviving a fall of eight storeys is something so rare the first comparison she thought of wasn't even human.
"Cats are known to survive falls from significant heights. Their flexible bodies being able to absorb the shock of free fall," said Béla Joos, from the University of Ottawa.
"The window cleaner most likely survived because he fell through the glass solarium."
A select society of famous fallers
Precious few survive long falls, but when they do they make news:
Flight attendant Vesna Vulovic holds the world record for surviving a fall, dropping 10,160 metres while inside part of a Yugoslav DC9 that was destroyed mid-air by a bomb in 1972.
RAF Flight Sergeant Nicholas Alkemade survived an 5,490-metre jump from a blazing Lancaster bomber in 1944.
Skydiver Michael Holmes fell 4,570 metres when his main chute tangled and his reserve failed. He broke an ankle.
Chris Saggers escaped with a broken elbow after falling 22 storeys from a Salford tower block.
Window washer Alcides Moreno survived a 47-storey fall off a Manhattan skyscraper in 2007.
- source: guardian.co.uk