Posted on May 26, 2018
Hers is far from being the greatest height from which someone has dropped and survived. According to the Guinness Book of World Records, flight attendant Vesna Vulović lived on after she was thrown from a DC-9 at an altitude of 33,333ft (10,160m) in 1972. Ulf Björnstig, senior professor of surgery at Sweden’s Umeå University, has co-authored several studies on the risks of parachute jumps. He describes the chances of living after an unimpeded fall of several thousand feet as “very small” and says Mrs Cilliers and Ms Vulović are “lucky cases”. But after a point, the height from which a person falls won’t make a difference to how fast they are going. It’s estimated that the human body in freefall reaches 99% of its terminal velocity (full and final speed) after dropping 573m (1,880ft), which usually takes 13 to 14 seconds. Mrs Cilliers came down in a ploughed field near Netheravon Airfield, on Salisbury Plain, Wiltshire, breaking her pelvis and ribs and fracturing some vertebrae. The surface has been described as unusually soft. Prof Björnstig says someone reaching terminal velocity needs at least half a metre of give – or deceleration distance – in the surface or object they hit to avoid fatal injuries. He recommends “forgiving structures”, such as snow, a swamp or the branches of a tree.