Wilbur Wright.

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Wilbur Wright.
Wilbur Wright (1867-1912), American aeronautical engineer who worked with his brother, Orville Wright, to build and fly the first airplane.
Wilbur, the elder of the two brothers, was born in Millville, Indiana. He was the third of five Wright children. Their father was a bishop of the United Brethren Church.
Wilbur went to high school in Dayton, Ohio, with his brother Orville. The boys shared an interest in mechanical things and learned as much about mathematics and
engineering as they could. Wilbur left high school before finishing his courses, and neither brother formally graduated. After leaving school, the brothers made several
attempts at editing and printing small local newspapers. In 1892 they formed the Wright Cycle Company. For the next ten years they designed, built, and sold bicycles.
The Wright brothers must have been aware of the possibility of powered flight and some of the efforts being made toward that end. The work of German aeronautical
pioneer Otto Lilienthal in the 1890s inspired the Wrights to pursue their own glider and airplane designs. Lilienthal died in a glider crash in 1896, convincing Wilbur that
the stability of the design and the skill of the pilot were as important as getting an airplane into the air.
The Wright brothers concentrated on developing techniques to stabilize and provide directional control for their gliders from 1896 to 1899. In August 1899 they flew a
kite with a wingspan of about 1.5 m (5 ft). The kite incorporated controls that could twist the ends of the wings. This wing-warping technique provided stability and
directional control and was the forerunner of the idea of ailerons. Ailerons are flaps on the trailing edges of modern airplane wings that move independently of the wings
to provide stability and steering controls. See Airplane: Control Components.
In 1900 the Wrights built a larger kite with a 5-m (17-ft) wingspan that could carry a pilot. They decided to begin their test flights near Kitty Hawk, North Carolina,
because the steady winds provided power for their flights and the sandy banks made crashing safer for machines and pilots. The kite flew well and even carried Wilbur
for a few seconds of piloted flight.
In July 1901 they returned to Kitty Hawk and built a wooden glider that had sledlike runners. They worked at Kill Devil Hills, where there were large sand dunes over
which the runners could glide. Their new machine was longer than the previous model and its wings were arched differently. It also had a hand-operated elevator--a
flap on the horizontal stabilizer on the tail that could control up-and-down movement. The brothers again achieved encouraging results, particularly after they
experimented with other wing arches. However, there were still problems with stability and control.
During late 1901 and early 1902 the Wrights built a small wind tunnel and tested various wing designs and wing arches. In the course of these tests, they compiled the
first accurate tables of lift and drag, the important parameters that govern flight and stability. They constructed a new glider with a 10 m (32 ft) wingspan in mid-1902.
At first the glider had two vertical fins mounted behind the wings. The brothers still found it difficult to turn with this design, so they transformed the double fin to a
single moveable rudder at the rear of the glider. This configuration proved so successful that they decided to attempt powered flight the following summer.
During late 1902 and early 1903 they searched in vain for a suitable engine for their craft and for knowledge of propeller design. No existing engines that provided the
power required were light enough to be practical to carry aboard an airplane. They eventually constructed their own 9-kilowatt (12-horsepower) motor and made their
own propeller, which moved air very efficiently. After some initial trouble with the propeller shafts, the first Wright Biplane took to the air and made a successful flight
on December 17, 1903, at Kill Devil Hills near Kitty Hawk. The airplane had a wingspan of 12 m (40 ft) and weighed 340 kg (750 lb) with the pilot. The two brothers
took turns flying the plane. Wilbur, in the last of the flights, stayed in the air for 59 seconds and traveled 260 m (852 ft) at speeds a little under 16 km/h (10 mph).
The following year the Wrights replaced the engine with a more powerful 12-kilowatt (16-horsepower) engine and separated the rudder controls from the controls that
changed the shape of the wing. They tested their new model in their hometown of Dayton, learning to make longer flights and tighter turns.
In 1905 the Wrights were sufficiently confident of their design to offer it to the United States War Department. The following year they patented their control system,
including the elevator, rudder, and wing-warping controls. Although they spent time patenting and finding markets for their machines during the next few years, they
did not feel sufficiently confident to exhibit their airplanes publicly until 1908. That year Wilbur demonstrated the plane in France, while Orville flew in the United States.
In 1909 Wilbur flew in Italy and Orville in Berlin, Germany. The airplanes were now sufficiently well controlled and stable enough to allow Wilbur to make a flight of 32
km (20 miles) in the United States.
During the next few years the brothers and their Wright Company continued building airplanes, but their competitors gained ground. In 1912 Wilbur died in Dayton,
Ohio, of typhoid fever. By 1918 the Wrights' patents were under pressure.

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