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Flight Sep 18, 2007 2:00/1:00 MT/PT
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 Humans
have dreamed about flying for thousands of years. They probably watched
birds, insects, bats, or leaves and imagined and wondered what it must
be like. |
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| However, it took many years for humans to grow and understand some properties of the earth and air and be able to measure accurately, develop theories, and predict outcomes. Only then could people build the wings and engines needed to fly. | |||||||||
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THE
HISTORY
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In 1670 Giovanni
Borelli attempted to use artificial wings for flying and proved that
human muscles aren't strong enough |
 In
1492 an Italian scientist, artist, and inventor, Leonardo da Vinci, observed
the flight of birds and analyzed their anatomy. He designed parachutes,
helicopters and flying machines that looked quite like the early attempts
at flying in the 1900's. |
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 In 1783 two men inflated a balloon with hot air. It then rose into the sky. |
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THE
WRIGHT BROTHERS
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However, it
was Wilbur and Orville Wright who, in 1903, made the first flight "...in
the history of the world in which a machine carrying a man had raised
itself by its own power into the air in full flight, had sailed forward
without reduction of |
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2
KINDS OF FLIGHT
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Gliding
Flight is accomplished with little or no movement or flapping of
wings. Leaves, maple seeds, or dandelion seeds seem to float with the
wind but they aren't true flyers. |
True
Flight is accomplished only by birds, insects, and bats. These are
the only animals able to move themselves through the air for a long
period of time by flapping their wings. Some birds also glide for awhile
but still need to flap their wings to stay in the air. |
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Did
you know that some fish fly? They use their fins and tails to move through
the air.
Flying squirrels have flaps of skin that connect their front and back legs. There are even flying frogs, lizards, snakes. Bats are flying mammals.   
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The
science that was developed to build flying machines is called aeronautics.
AERONAUTICS is the science of flight. |
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There
are 4 aerodynamic forces which are present when air is moving past an
object. WEIGHT, LIFT,
DRAG, and THRUST
must be understood before anyone can design an aircraft.
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Lift
is the upward force that works against gravity
and weight. |
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| Thrust is the forward push made when an engine turns a propeller. The propeller is shaped to push the air backwards. This results in a reaction force(thrust) on the propeller that moves the aircraft forwards. | |||||||||
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Around
350 BC the Chinese began to make kites. A kite is a form of a 
speed
and had finally landed at a point as high as that from which it started."
