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History of Flight
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From prehistoric times, humans have watched the flight of
birds, and longed to imitate them, but lacked the power to do
so. Logic dictated that if the small muscles of birds can lift
them into the air and sustain them, then the larger muscles
of humans should be able to duplicate the feat. No one knew
about the intricate mesh of muscles, sinew, heart, breathing
system, and devices not unlike wing flaps, variable-camber
and spoilers of the modern airplane that enabled a bird to
fly. Still, thousands of years and countless lives were lost in
attempts to fly like birds.
The identity of the first “bird-men” who fitted themselves
with wings and leapt off of cliffs in an effort to fly are lost in
time, but each failure gave those who wished to fly questions
that needed to be answered. Where had the wing flappers
gone wrong? Philosophers, scientists, and inventors offered
solutions, but no one could add wings to the human body
and soar like a bird. During the 1500s, Leonardo da Vinci
filled pages of his notebooks with sketches of proposed
flying machines, but most of his ideas were flawed because
he clung to the idea of birdlike wings. [Figure 1-1] By
1655, mathematician, physicist, and inventor Robert Hooke
concluded that the human body does not possess the strength
to power artificial wings. He believed human flight would
require some form of artificial propulsion.
The quest for human flight led some practitioners in another
direction. In 1783, the first manned hot air balloon, crafted
by Joseph and Etienne Montgolfier, flew for 23 minutes.
Ten days later, Professor Jacques Charles flew the first gas
balloon. A madness for balloon flight captivated the public’s
imagination and for a time flying enthusiasts turned their
expertise to the promise of lighter-than-air flight. But for
all its majesty in the air, the balloon was little more than a
billowing heap of cloth capable of no more than a one-way,
downwind journey.
Balloons solved the problem of lift, but that was only one of
the problems of human flight. The ability to control speed and
direction eluded balloonists. The solution to that problem lay
in a child’s toy familiar to the East for 2,000 years, but not
introduced to the West until the 13th century—the kite. The
kites used by the Chinese for aerial observation, to test winds
for sailing, as a signaling device, and as a toy, held many of
the answers to lifting a heavier-than-air device into the air.
One of the men who believed the study of kites unlocked
the secrets of winged flight was Sir George Cayley. Born
in England 10 years before the Mongolfier balloon flight,
Cayley spent his 84 years seeking to develop a heavier-thanair
vehicle supported by kite-shaped wings. [Figure 1-2] The
“Father of Aerial Navigation,” Cayley discovered the basic
principles on which the modern science of aeronautics is
founded; built what is recognized as the first successful flying
model; and tested the first full-size man-carrying airplane. 
For the half-century after Cayley’s death, countless scientists,
flying enthusiasts, and inventors worked toward building
a powered flying machine. Men, such as William Samuel
Henson, who designed a huge monoplane that was propelled
by a steam engine housed inside the fuselage, and Otto
Lilienthal, who proved human flight in aircraft heavier than
air was practical, worked toward the dream of powered flight.
A dream turned into reality by Wilbur and Orville Wright at
Kitty Hawk, North Carolina, on December 17, 1903.
The bicycle-building Wright brothers of Dayton, Ohio, had
experimented for 4 years with kites, their own homemade
wind tunnel, and different engines to power their biplane. One
of their great achievements in flight was proving the value of
the scientific, rather than a build-it-and-see approach. Their
biplane, The Flyer, combined inspired design and engineering
with superior craftsmanship. [Figure 1-3] By the afternoon
of December 17th, the Wright brothers had flown a total of
98 seconds on four flights. The age of flight had arrived.