› added 4 years ago

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TIL helicopter rotor blades spin at a fairly constant speed and only gain lift by altering the angle of the blades. The centrifugal force is too much to attempt to alter the blade RPM enough to generate lift.

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ObWL TIL that in 120, Genghis Khan was shot in the neck during a battle, and asked the defeated army who had shot “his horse”, trying to downplay the injury. The archer voluntarily confessed to shooting Genghis Khan and refused to beg for mercy, so the Khan spared him, turning him into a great general.
OEAY TIL In 1960, Slinky inventor Richard James left his wife and their six children to join a cult down in Bolivia. His wife, Betty, took over and turned the failing company completely around. In 2001, Betty was inducted into the Toy Industry Hall of Fame.
R71Qa TIL the 2013 NASA Astronaut class, which had 4 men and 4 women, is nicknamed the "8-balls"
J1Lov TIL The first air raid in WWII on the German capital was carried out on the night of June 7, 1940, by a lone French Farman F.223.4 long-range bomber nicknamed "Jules Verne". The crew manually dropped bombs, primarily targeting the Siemens factory, and successfully returned to their base in France.
nW7rB TIL Bees only poop in perfact weather. They will hold for months if needed.