The Wright brothers—Orville (August 19, 1871 – January 30, 1948) and Wilbur (April 16, 1867 – May 30, 1912)—were two American aviation pioneers generally credited with inventing, building, and flying the world's first successful motor-operated airplane.

They made the first controlled, sustained flight of a powered, heavier-than-air aircraft with the Wright Flyer on December 17, 1903, 4 mi (6 km) south of Kitty Hawk, North Carolina.

From 1900 until their first powered flights in late 1903, they conducted extensive glider tests that also developed their skills as pilots.

Wilbur was born near Millville, Indiana, in 1867; Orville in Dayton, Ohio, in 1871.

The other Wright siblings were Reuchlin (1861–1920), Lorin (1862–1939), Katharine (1874–1929), and twins Otis and Ida (born 1870, died in infancy).

Because of their father's position as a bishop in the Church of the United Brethren in Christ, he traveled often and the Wrights frequently moved—twelve times before finally returning permanently to Dayton in 1884.

In 1878 when the family lived in Cedar Rapids, Iowa, their father brought home a toy helicopter for his two younger sons.

The family's abrupt move in 1884 from Richmond, Indiana, to Dayton, Ohio, where the family had lived during the 1870s, prevented Wilbur from receiving his diploma after finishing four years of high school.

The diploma was awarded posthumously to Wilbur on April 16, 1994, which would have been his 127th birthday.

In late 1885 or early 1886 Wilbur was struck in the face by a hockey stick while playing an ice-skating game with friends, resulting in the loss of his front teeth.

Orville dropped out of high school after his junior year to start a printing business in 1889, having designed and built his own printing press with Wilbur's help.

In April 1890 they converted the paper to a daily, The Evening Item, but it lasted only four months.

Capitalizing on the national bicycle craze (spurred by the invention of the safety bicycle and its substantial advantages over the penny-farthing design), in December 1892 the brothers opened a repair and sales shop (the Wright Cycle Exchange, later the Wright Cycle Company) and in 1896 began manufacturing their own brand.

In the early or mid-1890s they saw newspaper or magazine articles and probably photographs of the dramatic glides by Otto Lilienthal in Germany.

In May 1899 Wilbur wrote a letter to the Smithsonian Institution requesting information and publications about aeronautics.

The death of British aeronaut Percy Pilcher in another hang gliding crash in October 1899 only reinforced their opinion that a reliable method of pilot control was the key to successful—and safe—flight.

They deliberately designed their 1903 first powered flyer with anhedral (drooping) wings, which are inherently unstable, but less susceptible to upset by gusty cross winds.

In July 1899 Wilbur put wing warping to the test by building and flying a biplane kite with a five-foot (1.5 m) wingspan.

In 1900 the brothers went to Kitty Hawk, North Carolina, to begin their manned gliding experiments.

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.

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 Otto Lilienthal had published.

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 their father, Bishop Wright, if Orville got injured.

The brothers flew the glider for only a few days in the early autumn of 1900 at Kitty Hawk.

These incidents wedded the Wrights even more strongly to the canard design, which they did not give up until 1910.

Intent on confirming the correct Smeaton value, Wilbur performed his own calculations using measurements collected during kite and free flights of the 1901 glider.

They then built a six-foot (1.8m) wind tunnel in their shop and between October and December 1901 conducted systematic tests on dozens of miniature wings.

The tests yielded a trove of valuable data never before known and showed that the poor lift of the 1900 and 1901 gliders was entirely due to an incorrect Smeaton value, and that Lilienthal's published data were fairly accurate for the tests he had done.

Before the detailed wind tunnel tests, Wilbur traveled to Chicago at Chanute's invitation to give a lecture to the Western Society of Engineers on September 18, 1901.

With this knowledge, and a more accurate Smeaton number, the Wrights designed their 1902 glider.

The 1901 wings had significantly greater curvature, a highly inefficient feature the Wrights copied directly from Lilienthal.

With characteristic caution, the brothers first flew the 1902 glider as an unmanned kite, as they had done with their two previous versions.

By 1902 they realized that wing-warping created "differential drag" at the wingtips.

With their new method the Wrights achieved true control in turns for the first time on October 8, 1902, a major milestone.

On March 23, 1903, the Wrights applied for their famous patent for a "Flying Machine", based on their successful 1902 glider.

Some aviation historians believe that applying the system of three-axis flight control on the 1902 glider was equal to, or even more significant, than the addition of power to the 1903 Flyer.

Peter Jakab of the Smithsonian asserts that perfection of the 1902 glider essentially represents invention of the airplane.

In 1903 the brothers built the powered Wright Flyer, using their preferred material for construction, spruce, a strong and lightweight wood, and Pride of the West muslin for surface coverings.

Wilbur made a March 1903 entry in his notebook indicating the prototype propeller was 66% efficient.

After the shafts were replaced (requiring two trips back to Dayton), Wilbur won a coin toss and made a three-second flight attempt on December 14, 1903, stalling after takeoff and causing minor damage to the Flyer.

Because December 13, 1903, was a Sunday, the brothers did not make any attempts that day, even though the weather was good, so their first powered test flight happened on the 121st anniversary of the first hot air balloon test flight that the Montgolfier brothers had done, on December 14, 1782.

The brothers shipped the airplane home, and years later Orville restored it, lending it to several U.S. locations for display, then to a British museum (see Smithsonian dispute below), before it was finally installed in 1948 in the Smithsonian Institution in Washington, D.C., its current residence.

Modern analysis by Professor Fred E. C. Culick and Henry R. Jex (in 1985) has demonstrated that the 1903 Wright Flyer was so unstable as to be almost unmanageable by anyone but the Wrights, who had trained themselves in the 1902 glider.

In a recreation attempt on the event's 100th anniversary on December 17, 2003, Kevin Kochersberger, piloting an exact replica, failed in his effort to match the success that the Wright brothers had achieved with their piloting skill.

In 1904 the Wrights built the Wright Flyer II.

The first flights in 1904 revealed problems with longitudinal stability, solved by adding ballast and lengthening the supports for the elevator.

On September 20, 1904, Wilbur flew the first complete circle in history by a manned heavier-than-air powered machine, covering 4,080 feet (1,244 m) in about a minute and a half.

The Wrights scrapped the battered and much-repaired aircraft, but saved the engine, and in 1905 built a new airplane, the Flyer III.

In 1904 Ohio beekeeping businessman Amos Root, a technology enthusiast, saw a few flights including the first circle.

The Paris edition of the Herald Tribune headlined a 1906 article on the Wrights "FLYERS OR LIARS?"

James M. Cox, publisher at that time of the Dayton Daily News (later governor of Ohio and Democratic presidential nominee in 1920), expressed the attitude of newspapermen—and the public—in those days when he admitted years later, "Frankly, none of us believed it."

October 1904, the brothers were visited by the first of many important Europeans they would befriend in coming years, Colonel J. E. Capper, later superintendent of the Royal Balloon Factory.

In 1906 skeptics in the European aviation community had converted the press to an anti-Wright brothers stance.

The Paris edition of the New York Herald summed up Europe's opinion of the Wright brothers in an editorial on February 10, 1906: "The Wrights have flown or they have not flown.

The Wright brothers made no flights at all in 1906 and 1907.

The brothers turned their attention to Europe, especially France, where enthusiasm for aviation ran high, and journeyed there for the first time in 1907 for face-to-face talks with government officials and businessmen.

With further input from the Wrights, the U.S. Army Signal Corps issued Specification #486 in December 1907, inviting bids for construction of a flying machine under military contract.

In early 1908 the brothers also agreed to a contract with a French company.

In May they went back to Kitty Hawk with their 1905 Flyer to practice in private for their all-important public demonstration flights, as required by both contracts.

Their contracts required them to fly with a passenger, so they modified the 1905 Flyer by installing two seats and adding upright control levers.

After tests with sandbags in the passenger seat, Charlie Furnas, a helper from Dayton, became the first fixed-wing aircraft passenger on a few short flights May 14, 1908.

In October 1911, Orville Wright returned to the Outer Banks again, to conduct safety and stabilization tests with a new glider.

On October 24, he soared for 9 minutes and 45 seconds, a record that held for almost 10 years, when gliding as a sport began in the 1920s.

October 7, 1908, Edith Berg, the wife of the brothers' European business agent, became the first American woman passenger when she flew with Wilbur—one of many passengers who rode with him that autumn.

Madame Bollée had been in the latter stages of pregnancy when Wilbur arrived in LeMans in June 1908 to assemble the Flyer.

Wilbur promised her that he would make his first European flight the day her baby was born which he did, August 8, 1908.

Orville followed his brother's success by demonstrating another nearly identical Flyer to the United States Army at Fort Myer, Virginia, starting on September 3, 1908.

In January 1909 Orville and Katharine joined him in France, and for a time they were the three most famous people in the world, sought after by royalty, the rich, reporters and the public.

In July 1909 Orville, with Wilbur assisting, completed the proving flights for the U.S. Army, meeting the requirements of a two-seater able to fly with a passenger for an hour at an average of speed of 40 miles an hour (64 km/h) and land undamaged.

They sold the airplane to the Army's Aeronautical Division, U.S. Signal Corps for $30,000 (equivalent to $854,000 in 2019), including a $5,000 bonus for exceeding the speed specification.

On May 25, 1910, back at Huffman Prairie, Orville piloted two unique flights.

The Wright brothers wrote their 1903 patent application themselves, but it was rejected.

In January 1904, they hired Ohio patent attorney Henry Toulmin, and on May 22, 1906, they were granted U.S. Patent 821393 for "new and useful Improvements in Flying Machines".

The patent illustrates a non-powered flying machine—namely, the 1902 glider.

The patent also describes the steerable rear vertical rudder and its innovative use in combination with wing-warping, enabling the airplane to make a coordinated turn, a technique that prevents hazardous adverse yaw, the problem Wilbur had when trying to turn the 1901 glider.

Soon after the historic July 4, 1908, one-kilometer flight by Curtiss in the AEA June Bug, the Wrights warned him not to infringe their patent by profiting from flying or selling aircraft that used ailerons.

Curtiss was at the time a member of the Aerial Experiment Association (AEA), headed by Alexander Graham Bell, where in 1908 he had helped reinvent wingtip ailerons for their Aerodrome No. 2, known as the AEA White Wing (the AEA's other members became dismayed when Curtiss unexpectedly dropped out of their organization; they later came to believe he had sold the rights to their joint innovation to the United States Government).Curtiss refused to pay license fees to the Wrights and sold an airplane equipped with ailerons to the Aeronautic Society of New York in 1909.

Despite a pro-Wright ruling in France, legal maneuvering dragged on until the patent expired in 1917.

A German court ruled the patent not valid because of prior disclosure in speeches by Wilbur Wright in 1901 and Chanute in 1903.

The Wright brothers won their initial case against Curtiss in February 1913 when a judge ruled that ailerons were covered under the patent.

From 1910 until his death from typhoid fever in 1912, Wilbur took the leading role in the patent struggle, traveling incessantly to consult with lawyers and testify in what he felt was a moral cause, particularly against Curtiss, who was creating a large company to manufacture aircraft.

The Wrights' preoccupation with the legal issue stifled their work on new designs, and by 1911 Wright airplanes were considered inferior to those of European makers.

In January 1914, a U.S. Circuit Court of Appeals upheld the verdict against the Curtiss company, which continued to avoid penalties through legal tactics.

In fact, he was planning to sell the company and departed in 1915.

In 1917, with World War I underway, the U.S. government pressured the industry to form a cross-licensing organization, the Manufacturers Aircraft Association, to which member companies paid a blanket fee for the use of aviation patents, including the original and subsequent Wright patents.

The "patent war" ended, although side issues lingered in the courts until the 1920s.

In a twist of irony, the Wright Aeronautical Corporation (successor to the Wright-Martin Company), and the Curtiss Aeroplane company, merged in 1929 to form the Curtiss-Wright Corporation, which remains in business today producing high-tech components for the aerospace industry.

In business The Wright Company was incorporated on November 22, 1909.

In mid-1910, the Wrights changed the design of the Wright Flyer, moving the horizontal elevator from the front to the back and adding wheels although keeping the skids as part of the undercarriage unit.

There were not many customers for airplanes, so in the spring of 1910 the Wrights hired and trained a team of salaried exhibition pilots to show off their machines and win prize money for the company—despite Wilbur's disdain for what he called "the mountebank business".

Before the year was over, pilots Ralph Johnstone and Arch Hoxsey died in air show crashes, and in November 1911 the brothers disbanded the team on which nine men had served (four other former team members died in crashes afterward).The Wright Company transported the first known commercial air cargo on November 7, 1910, by flying two bolts of dress silk 65 miles (105 km) from Dayton to Columbus, Ohio, for the Morehouse-Martens Department Store, which paid a $5,000 fee.

Between 1910 and 1916 the Wright Brothers Flying School at Huffman Prairie trained 115 pilots who were instructed by Orville and his assistants.

Several trainees became famous, including Henry "Hap" Arnold, who rose to Five-Star General, commanded U.S. Army Air Forces in World War II, and became the first head of the U.S. Air Force; Calbraith Perry Rodgers, who made the first coast-to-coast flight in 1911 (with many stops and crashes) in a Wright Model EX named the "Vin Fiz" (after the sponsor's grape soft drink); and Eddie Stinson, founder of the Stinson Aircraft Company.

The death toll reached 11 by 1913, half of them in the Wright model C. All six model C Army airplanes crashed.

Samuel Pierpont Langley, secretary of the Smithsonian Institution from 1887 until his death in 1906, experimented for years with model flying machines and successfully flew unmanned powered fixed-wing model aircraft in 1896 and 1903.

Two tests of his manned full-size motor-driven Aerodrome in October and December 1903, however, were complete failures.

The Smithsonian based its claim for the Aerodrome on short test flights Glenn Curtiss and his team made with it in 1914.

Orville responded by lending the restored 1903 Kitty Hawk Flyer to the London Science Museum in 1928, refusing to donate it to the Smithsonian while the Institution "perverted" the history of the flying machine.

In 1942, after years of bad publicity, and encouraged by Wright biographer Fred C. Kelly, the Smithsonian finally relented by publishing, for the first time, a list of the Aerodrome modifications and recanting misleading statements it had made about the 1914 tests.

On November 23, 1948, the executors of Orville's estate signed an agreement for the Smithsonian to purchase the Flyer for one dollar.

The agreement reads, in part, "Neither the Smithsonian Institution or its successors, nor any museum or other agency, bureau or facilities administered for the United States of America by the Smithsonian Institution or its successors shall publish or permit to be displayed a statement or label in connection with or in respect of any aircraft model or design of earlier date than the 1903 Wright Aeroplane, claiming in effect that such aircraft was capable of carrying a man under its own power in controlled flight.

After a ceremony in the Smithsonian museum, the Flyer went on public display on December 17, 1948, the 45th anniversary of the only day it was flown successfully.

Following a brief training flight he gave to a German pilot in Berlin in June 1911, Wilbur never flew again.

Wilbur did not live to see its completion in 1914.

He became ill on a business trip to Boston in April 1912.

After returning to Dayton in early May 1912, worn down in mind and body, he fell ill again and was diagnosed with typhoid fever.

He won the prestigious Collier Trophy in 1914 for development of his automatic stabilizer on the brothers' Wright Model E. Sharing Wilbur's distaste for business but not his brother's executive skills, Orville sold the company in 1915.

The Wright Company then became part of Wright-Martin in 1916.

After 42 years living at their residence on 7 Hawthorn Street, Orville, Katharine and their father, Milton, moved to Hawthorn Hill in the spring of 1914.

Milton died in his sleep on April 3, 1917, at the age of 88.

Katharine married Henry Haskell of Kansas City, a former Oberlin classmate, in 1926.

He finally agreed to see her, apparently at Lorin's insistence, just before she died of pneumonia on March 3, 1929.

In 1930, he received the first Daniel Guggenheim Medal established in 1928 by the Daniel Guggenheim Fund for the Promotion of Aeronautics.

In 1936, he was elected a member of the National Academy of Sciences.

In 1939, President Franklin Delano Roosevelt issued a presidential proclamation which designated the anniversary of Orville's birthday as National Aviation Day, a national observation that celebrates the development of aviation.

On April 19, 1944, the second production Lockheed Constellation, piloted by Howard Hughes and TWA president Jack Frye, flew from Burbank, California, to Washington, D.C. in 6 hours and 57 minutes (2300 mi, 330.9 mph).

Orville's last major project was supervising the reclamation and preservation of the 1905 Wright Flyer III, which historians describe as the first practical airplane.

Orville died at age 76 on January 30, 1948, over 35 years after his brother, following his second heart attack, having lived from the horse-and-buggy age to the dawn of supersonic flight.

First powered flight claims are made for Clément Ader, Gustave Whitehead, Richard Pearse, and Karl Jatho for their variously documented tests in years prior to and including 1903.

Claims that the first true flight occurred after 1903 are made for Traian Vuia and Alberto Santos-Dumont.

Notwithstanding the competition between those two states, in 1937 the Wrights' final bicycle shop and home were moved from Dayton to Greenfield Village in Dearborn, Michigan, where they remain.