In the 21st Century we take for granted that we can fly anywhere or receive a package fromanywhere in the world within one day. This would have ben beyond one's wildest dreams at the start of the 20th Century. Yet during the first sixty years of that century, particularly between 1930 and 1960, a few visionary engineers, generals, politicians, and businessmen led the creation of the commercial jet aviation system we now enjoy. This story is contingent on the invention of the airplane itself as well as the jet engine and ancillary parts, like radar; on massive military investment inspired by both World War I and the Cold War; on competition among aircraft manufacturers and among airlines; on government infrastructure projects providing airports big enough for jets; and on public acceptance of jet travel. The men (they were almost al men) who made this happen took none of this for granted. Delta Airlines president C E Wellman, upon ordering its first jet planes ni 1956, said, "We are buying airplanes that haven't ben fully designed with millions of dollars we don't have and are going ot operate them of airports that are too small, in an air traffic control system that si too slow and we must fil them with more passengers than we have ever carried before." This dissertation tells this complex story., and argues that technological change is both highly contingent and deeply intertwined with cultural, political and economic factors. It demonstrates that competition, at all levels, plays amajor role ni inspiring and shaping technological change.