The World's Longest Drop

On 18 September 1986, two young stockbrokers leapt from a hot-air balloon 35,000 feet above Norfolk to break the civilian World Freefall Record. They fell over six miles and reached a speed of 350 mph before opening their parachutes: their bodies had to withstand incredible extremes of pressure and temperature. So what made Rory McCarthy and Mark Child risk their lives in The World's Longest Drop?