At the turn of the century, the Wright brothers were building their bicycle planes.<p>Within 10 years, by the start of WW1 there were triplanes fit for war use. By the end of the war, Germany had metal planes with a single wing... not all that different from a modern crop duster.<p>Amazing what the competitive (and "save our nation") pressure of an industrial war can do.<p>Immediately after the great war, helicopters and all sorts of new planes were invented. By the time WW2 rolled around 20 years later, there were Spitfires & heavy bombers. Japan had floating airports. The sky became the place where land, naval and air battles were won or lost.<p>The pace kept up in the generation after the war. Jet engines. 3 generations of jet fighters, each outclassing the last. Airliners more or less like modern ones. The f-15 is still The Cavalary. 747s are not out of place in a modern airport. 1967 & 1977 respectively.<p>50 years of peace, 50 years of stagnation.<p>This is a lesson about people and a lesson about progress.