While even short drops can be lethal, people have survived horrendous falls. In 1972, Vesna Vulovic, a cabin attendant, survived a 10,160m fall when the DC-9 she was in exploded over what is now the Czech Republic. Earlier this week, a 102-year-old woman survived after toppling from her fourth-floor balcony in Turin. Fortunately, her fall was broken by a children's playhouse.
In very high falls, bodies can reach terminal velocity, the speed at which air resistance becomes so high it cancels out the acceleration due to gravity. Once at terminal velocity, you can fall as far as you like and you won't gather any more speed.
Vulovic undoubtedly reached terminal velocity before hitting the ground, but it is hard to achieve when falling from a building. "A free-falling 120lb [54kg] woman would have a terminal velocity of about 38m per second," says Howie Weiss, a maths professor at Penn State University. "And she would achieve 95% of this speed in about seven seconds." That equates to a fall of around 167m, which is nearer 55 storeys high.
Falls can kill by inflicting damage to any number of vital organs, but the most common reason is due to a key artery's route through the body. "Most people who fall from a height die because they fracture their spine near the top and so transect the aorta which carries blood out of the heart," says Sean Hughes, professor of surgery at Imperial College, London.
Landing on your side might be the best way to survive a fall, adds Hughes. It doesn't take much of a fall to cause damage. "From a height of 3m you could fracture your spine," he says. "At around 10m, you're looking at very serious injuries."
Ian Sample
