How about 300 feet? Last fall, a remarkable case report appeared in an little-noticed journal, the Scandinavian Journal of Trauma, Resuscitation, and Emergency Medicine. The article begins with this astonishing sentence:
"We report the case of a 28-year old rock climber who survived an 'unsurvivable' injury consisting of a vertical free fall from 300 feet onto a solid rock surface."This is no ordinary case report. The accident happened when a 28-year-old woman and her boyfriend, both experienced rock climbers, were climbing in the Rocky Mountains in Colorado. Both were wearing helmets. The woman took the lead on the final pitch of a 300-foot (90-meter) climb. At the very top, after securing the rope, her climbing harness failed. She fell 200 feet straight down, hit a flat rock surface, then fell another 100 feet. Her boyfriend climbed down as rapidly as he could, and found her at the bottom, alive. This appears to be the highest vertical free fall onto a hard surface that a human has been documented to survive.
The list of the climber's injuries, described in detail in the article, is frighteningly long. The article shows a picture of her, awake and off the respirator, on her 4th day in the hospital. (The patient agreed to have her case published along with her photo.) Despite her extensive injuries, including paralysis of both legs, she otherwise recovered remarkably well and "was transferred to her local community regional spinal cord rehabilitation center out-of-state at 2½ months after injury in excellent conditions."
The authors of the article focused on this question: if you fall a very, very long distance, how should you land? The authors of the study concluded that a critical factor in the climber's survival was that she landed feet first. As they wrote: " a fall on both feet represents the 'ideal' body to impact surface position with regard to survival from vertical falls." Landing feet first allows the lower body to absorb most of the deceleration force, as they illustrated in the figure reproduced here.
This case reminds me of a famous paper from BMJ back in 2003: "Parachute use to prevent death and major trauma related to gravitational challenge: systematic review of randomised controlled trials." In that paper, G.C.S. Smith and J.P. Pell complained that no one has ever done a properly controlled experiment to determine if parachutes really work.
"We were unable to identify any randomised controlled trials of parachute intervention," they wrote.They argued that "an adverse outcome after free fall is by no means inevitable," a point that the current study would seem to support. However, I can't agree with Smith and Pell's conclusion: "We think that everyone might benefit if the most radical protagonists of evidence based medicine organised and participated in a double blind, randomised, placebo controlled, crossover trial of the parachute."