Wright brothers
he Wright brothers, Orville (August 19, 1871 – January 30, 1948) and Wilbur (April 16, 1867 – May 30, 1912), were two American brothers, inventors, and aviation pioneers who are credited]
with inventing and building the world's first successful airplane and making the first controlled, powered and sustained heavier-than-air human flight, on December 17, 1903. From 1905 to 1907, the brothers developed their flying machine into the first practical fixed-wing aircraft. Although not the first to build and fly experimental aircraft, the Wright brothers were the first to invent aircraft controls that made fixed-wing powered flight possible
The brothers' fundamental breakthrough was their invention of three-axis control, which enabled the pilot to steer the aircraft effectively and to maintain its equilibrium.] This method became and remains standard on fixed-wing aircraft of all kinds.] From the beginnig of their aeronautical work, the Wright brothers focused on developing a reliable method of pilot control as the key to solving "the flying problem". This approach differed significantly from other experimenters of the time who put more emphasis on developing powerful engines. Using a small homebuilt wind tunnel, the Wrights also collected more accurate data than any before, enabling them to design and build wings and propellers that were more efficient than any before. Their first U.S. patent, 821,393, did not claim invention of a flying machine, but rather, the invention of a system of aerodynamic control that manipulated a flying machine's surfaces.
They gained the mechanical skills essential for their success by working for years in their shop with printing presses, bicycles, motors, and other machinery. Their work with bicycles in particular influenced their belief that an unstable vehicle like a flying machine could be controlled and balanced with practice. From 1900 until their first powered flights in late 1903, they conducted extensive glider tests that also developed their skills as pilots. Their bicycle shop employeeCharlie Taylor became an important part of the team, building their first airplane engine in close collaboration with the brothers
The Wright brothers' status as inventors of the airplane has been subject to counter-claims by various parties. Much controversy persists over the many competing claims of early aviators. Historian Edward Roach argues that they were excellent self-taught engineers with a knack for tinkering more than for systematic research, but they proved to be poor businessmen
Toward flight
In July 1899 Wilbur put wing warping to the test by building and flying a biplane kite with a five-foot (1.5m) wingspan. When the wings were warped, or twisted, one end of the wings produced more lift and the other end less lift. The unequal lift made the wings tilt, or bank: the end with more lift rose, while the other end dropped, causing a turn in the direction of the lower end. The warping was controlled by four cords attached to the kite, which led to two sticks held by the kite flyer, who tilted them in opposite directions to twist the wings
n 1900 the brothers went to Kitty Hawk, North Carolina to begin their manned gliding experiments. In his reply to Wilbur's first letter, Octave Chanute had suggested the mid-Atlantic coast for its regular breezes and soft sandy landing surface. Wilbur also requested and examined U.S. Weather Bureau data, and decided on Kitty Hawk after receiving information from the government meteorologist stationed there.[38] Kitty Hawk, although remote, was closer to Dayton than other places Chanute had suggested, including California and Florida. The spot also gave them privacy from reporters, who had turned the 1896 Chanute experiments at Lake Michigan into something of a circus. Chanute visited them in camp each season from 1901 to 1903 and saw gliding experiments, but not the powered flights
Gliders
The Wrights based the design of their kite and full-size gliders on work done in the 1890s by other aviation pioneers. They adopted the basic design of the Chanute-Herring biplane hang glider ("double-decker" as the Wrights called it), which flew well in the 1896 experiments near Chicago, and used aeronautical data on lift that Lilienthal had published. The Wrights designed the wings with camber, a curvature of the top surface. The brothers did not discover this principle, but took advantage of it. The better lift of a cambered surface compared to a flat one was first discussed scientifically by Sir George Cayley. Lilienthal, whose work the Wrights carefully studied, used cambered wings in his gliders, proving in flight the advantage over flat surfaces. The wooden uprights between the wings of the Wright glider were braced by wires in their own version of Chanute's modified Pratt truss, a bridge-building design he used for his biplane glider (initially built as a triplane). The Wrights mounted the horizontal elevator in front of the wings rather than behind, apparently believing this feature would help to avoid, or protect them, from a nosedive and crash like the one that killed Lilienthal.] Wilbur incorrectly believed a tail was not necessary,] and their first two gliders did not have one. According to some Wright biographers, Wilbur probably did all the gliding until 1902, perhaps to exercise his authority as older brother and to protect Orville from harm as he did not want to have to explain to Bishop Wright if Orville got injured
| Wingspan | Wing area | Chord | Camber | Aspect ratio | Length | Weight | |
|---|---|---|---|---|---|---|---|
| 1900 | 17 ft 6 in (5.33 m) | 165 sq ft (15 m2) | 5 ft (2 m) | 1/20 | 3.5:1 | 11 ft 6 in (3.51 m) | 52 lb (24 kg) |
| 1901 | 22 ft (7 m) | 290 sq ft (27 m2) | 7 ft (2.1 m) | 1/12,*1/19 | 3:1 | 14 ft (4.3 m) | 98 lb (44 kg) |
| 1902 | 32 ft 1 in (9.78 m) | 305 sq ft (28 m2) | 5 ft (1.5 m) | 1/20–1/24 | 6.5:1 | 17 ft (5.2 m) | 112 lb (51 kg) |
* (This airfoil caused severe stability problems; the Wrights modified the camber on-site.)
1900 Glider
The brothers flew the glider for only a few days in the early autumn of 1900 at Kitty Hawk. In the first tests, probably on October 3, Wilbur was aboard while the glider flew as a kite not far above the ground with men below holding tether ropes.] Most of the kite tests were unpiloted, with sandbags or chains (and even a local boy as ballas
They tested wing-warping using control ropes from the ground. The glider was also tested unmanned while suspended from a small homemade tower. Wilbur (but not Orville) made about a dozen free glides on only a single day, October 20. For those tests the brothers trekked four miles (6 km) south to the Kill Devil Hills, a group of sand dunes up to 100 feet (30 m) high (where they made camp in each of the next three years). Although the glider's lift was less than expected (causing most tests to be unmanned), the brothers were encouraged because the craft's front elevator worked well and they had no accidents. However, the small number of free glides meant they were not able to give wing-warping a true test
The pilot lay flat on the lower wing, as planned, to reduce aerodynamic drag. As a glide ended, the pilot was supposed to lower himself to a vertical position through an opening in the wing and land on his feet with his arms wrapped over the framework. Within a few glides, however, they discovered the pilot could remain prone on the wing, headfirst, without undue danger when landing. They made all their flights in that position for the next five years
Wilbur (left) and Orville (right) as children in 1876
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