Skydiving

Abstract

If the reader, bored by extreme sports injuries, throws this book out the window, it will tumble and turn, catching air while descending down through earth’s relatively thick lower atmosphere. Medical textbooks or their readers do not really fall through air; they sink. Their sink rates can be lowered with extra drag, such as can be provided by a parachute (Greek/French: “against fall”). This principle was suggested in Chinese literature two millennia ago as a means to safely jump from a high object and possibly put to practical use in that country during the 1100s. Leonardo da Vinci designed a rigid-frame parachute in the 1480s, and reports of parachuting activities in Siam (Thailand) during the 1600s may have served as inspiration for European parachute designers in the 1700s [1–4]. The invention of the hot air balloon provided a high, mobile exit point from which a number of daredevil exhibition jumpers made parachuting known to a wider audience. Among early parachutists were Elisa Garnerin, who made 39 jumps from balloons in the early 1800s, and Käthe Paulus, who made 147 jumps at the end of the same century. In 1912, Albert Berry jumped from an airplane using a pack on the aircraft parachute system, and in 1914, Georgia Thompson performed a manual free fall activation of a parachute [1, 5].