Not really all that long ago. On December 17, 1903 at Kitty Hawk North Carolina, the first heavier than air aircraft took off under its own power. (Balloons and gliders had flown earlier.)
Not too often can one see a real image of a great moment in human history. Two bicycle mechanics changed the world that day. Why was “lift” so hard to figure out? Was da Vinci on the right track?