Flight

The Orville and Wilbur Wright flew under power in 1903. The first flight travelled only 120 feet but Wilbur flew 24.5 miles in 38 minutes in August 1904.

More powerful aircraft engines were developed during WW-1 but airframes were too fragile for aerial fighting.

H.Focke's transverse twin-rotor helicopter, broke all helicopter world records in 1937.

After WW-1, designers used duralumin airframes and smaller, monoplane wings for fighter aircraft like the Supermarine Spitfire.
At Midway, in 1942, American dive-bombers sank three of the four Japanese aircraft carriers.

I.Sikorsky developed the first practical single rotor helicopter with a single tail boom rotor and produced over 400 helicopters in WW-2.

The Messerschmitt Me 262 was the first jet fighter in action in 1944.

For maximum efficiency most jet aircraft need to cruise at about Mach 0.8 (610 mph) and at altitudes above 30,000 ft.

In 2021, with battery powered, contra-rotating propellers spinning at 2500 rpm, NASA's Dragonfly helicopter lifted off from the surface of Mars. It weighed only 2 pound.

WHO THE HELL ARE WE? is a series of short books and videos describing the evolution of civilization.

Almost everyone on the planet is five times wealthier than their ancestors only 50 years ago. This astonishing phenomenon has also improved health, education, and longevity. The cause; an explosive growth in ideas and productivity.

It began when we learned to control fire, evolved articulate speech and stumbled onto the way to create infinite wealth; free trade. The discovery of agriculture made us richer but we also learned how to destroy wealth. Great civilization grew up but then disappeared leaving only incredible ruins and ideas.

Later books detail some of the ideas and developments that increased the average life span from about 40 years to more than 80 and the average world income from less than $3 to more than $33 per person per day (and to $140 per day in some countries).