Wright Flyer
The Wright Flyer made the first sustained flight by a manned heavier-than-air powered and controlled aircraft on December 17, 1903. Invented and flown by brothers Orville and Wilbur Wright, it marked the beginning of the pioneer era of aviation.
The aircraft is a single-place biplane design with anhedral wings, front double elevator and rear double rudder. It used a gasoline engine powering two pusher propellers. Employing "wing warping", it was relatively unstable and very difficult to fly.
The Wright brothers flew it four times in a location now part of the town of Kill Devil Hills, about south of Kitty Hawk, North Carolina. The airplane flew on its fourth and final flight, but was damaged on landing, and wrecked minutes later when powerful gusts blew it over.
The brothers shipped the wreckage back to Dayton, and the aircraft never flew again. Orville later restored it and displayed it on several occasions. The Flyer joined the Smithsonian Institution's collection of historic aircraft in 1948 after the end of a long and bitter dispute between Orville and the Institution over its refusal to recognize the Flyer as the first successful airplane. Today, it is on display in a place of honor in the National Air and Space Museum in Washington, D.C.
Design and construction
The Flyer was based on the Wrights' experience testing gliders at Kitty Hawk between 1900 and 1902. Their last glider, the 1902 Glider, led directly to the design of the Wright Flyer.The Wrights built the aircraft in 1903 using spruce for straight members of the airframe and ash wood for curved components. The wings were designed with a 1-in-20 camber. The fabric for the wing was 100% cotton muslin called "Pride of the West", a type used for women's underwear. It had a warp of 107 threads per inch, a weft of 102, and a total thread count of 209.
Since they could not find a suitable automobile engine for the task, they commissioned their employee Charlie Taylor to build a new design from scratch, a lightweight gasoline engine, weighing, with a fuel tank. A sprocket chain drive, borrowing from bicycle technology, powered the twin propellers, which were also made by hand. In order to avoid the risk of torque effects from affecting the aircraft handling, one drive chain was crossed over so that the propellers rotated in opposite directions.
According to Taylor:
The long propellers were based on airfoil number 9 from their wind tunnel data, which provided the best "gliding angle" for different angles of attack. The propellers were connected to the engine by chains from the Indianapolis Chain Company, with a sprocket gear reduction of 23-to-8. Wilbur had calculated that slower turning blades generated greater thrust, and two of them were better than a single blade turning faster. Made from three laminations of spruce, the tips were covered with duck canvas, and the entire propeller painted with aluminum paint.
On November 5, 1903, the brothers tested their engine on the Wright Flyer at Kitty Hawk, but before they could tune the engine, the propeller hubs came loose. The drive shafts were sent back to Dayton for repair, and returned on 20 November. A hairline crack was discovered in one of the propeller shafts. Orville returned to Dayton on 30 November to make new spring steel shafts. On December 12, the brothers installed the new shafts on the Wright Flyer and tested it on their launching rail system that included a wheeled launching dolly. According to Orville:
In practice tests, they were able to achieve a propeller rpm of 351, with a thrust of, more than enough for their flyer.
The Wright Flyer was a canard biplane configuration, with a wingspan of, a camber of 1-20, a wing area of, and a length of. The right wing was longer because the engine was heavier than Orville or Wilbur. Unoccupied, the machine weighed. As with the gliders, the pilot flew lying on his stomach on the lower wing with his head toward the front of the craft in an effort to reduce drag. The pilot was left of center while the engine was right of center. He steered by moving a hip cradle in the direction he wished to fly. The cradle pulled wires to warp the wings, and simultaneously turn the rudder, for coordinated flight. The pilot operated the elevator lever with his left hand, while holding a strut with his right. The Wright Flyers "runway" was a track of 2x4s, which the brothers nicknamed the "Junction Railroad". The Wright Flyer skids rested on a launching dolly, consisting of a plank, with a wheeled wooden section. The two tandem ball bearing wheels were made from bicycle hubs. A restraining wire held the plane back, while the engine was running and the propellers turning, until the pilot was ready to be released.
The Wright Flyer had three instruments on board. A Veeder engine revolution recorder measured the number of propeller turns. A stopwatch recorded the flight time, and a Richard hand anemometer, attached to the front center strut, recorded the distance covered in meters.
Flight trials at Kitty Hawk
Upon returning to Kitty Hawk in 1903, the Wrights completed assembly of the Flyer while practicing on the 1902 Glider from the previous season. On December 14, 1903, they felt ready for their first attempt at powered flight. With the help of men from the nearby government life-saving station, the Wrights moved the Flyer and its launching rail to the incline of a nearby sand dune, Big Kill Devil Hill, intending to make a gravity-assisted takeoff. The brothers tossed a coin to decide who would get the first chance at piloting, and Wilbur won. The airplane left the rail, but Wilbur pulled up too sharply, stalled, and came down after covering in 3 seconds, sustaining little damage.Repairs after the abortive first flight took three days. When they were ready again on December 17, the wind was averaging more than, so the brothers laid the launching rail pointed into the wind on level ground near their camp. This time the wind, instead of an inclined launch, provided the necessary airspeed for takeoff. Because Wilbur already had the first chance, Orville took his turn at the controls. His flight, captured in a famous photograph, lasted 12 seconds for a total distance of – shorter than the wingspan of a Boeing 747. The brothers made three more flights, taking turns. The second and third flights were 175 and 200 feet in 12 and 15 seconds respectively. The fourth and last flight, by Wilbur, took 59 seconds to cover over the ground, moving through approximately a half mile of flowing air.
The flights reached about ten feet of altitude and were all essentially straight; turns were not attempted. Each landing was bumpy and unintended, and the fourth flight's landing broke the front elevator supports. The Wrights hoped to make repairs for a possible flight to Kitty Hawk village, but minutes later a heavy gust picked up the Flyer and tumbled it end over end, damaging it beyond any hope of quick repair. It was never flown again.
In 1904, the Wrights continued refining their designs and piloting techniques in order to obtain fully controlled flight. Major progress toward this goal was achieved with a new machine, the Wright Flyer II, in 1904 and even more decisively in 1905 with the Wright Flyer III, in which Wilbur made a 39-minute, nonstop circling flight on October 5.
Influence
The Flyer series of aircraft were the first to achieve controlled heavier-than-air flight, but some of the mechanical techniques the Wrights used to accomplish this were not influential for the development of aviation as a whole, although their theoretical achievements were. The Flyer design depended on wing-warping controlled by a hip cradle under the pilot, and a foreplane or "canard" for pitch control, features which would not scale and produced a hard-to-control aircraft. The Wrights' pioneering use of "roll control" by twisting the wings to change wingtip angle in relation to the airstream led to the more practical use of ailerons by others, such as Glenn Curtiss and Henri Farman. The Wrights' original concept of simultaneous coordinated roll and yaw control, which they discovered in 1902, perfected in 1903–1905, and patented in 1906, represents the solution to controlled flight and is used today on virtually every fixed-wing aircraft. The Wright patent included the use of hinged rather than warped surfaces for the forward elevator and rear rudder. Other features that made the Flyer a success were highly efficient wings and propellers, which resulted from the Wrights' exacting wind tunnel tests and made the most of the marginal power delivered by their early homebuilt engines; slow flying speeds ; and an incremental test/development approach. The future of aircraft design lay with rigid wings, ailerons and rear control surfaces. A British patent of 1868 for aileron technology had apparently been completely forgotten by the time the 20th century dawned.After a single statement to the press in January 1904 and a failed public demonstration in May, the Wright Brothers did not publicize their efforts, and other aviators who were working on the problem of flight were thought by the press to have preceded them by many years. After their successful demonstration flight in France on August 8, 1908, they were accepted as pioneers and received extensive media coverage.
In 1909, the Wright Military Flyer became the world's first military aircraft after successful tests on June 3, 1909. This airplane was purchased by the army but was never used in combat; it was, however, used to train some pilots. It was donated to the Smithsonian Institution in 1911 and is on display in the Early Flight exhibit at the National Air and Space Museum. A modified version, the Wright Model B, was produced in larger numbers by the Wright brothers and was used by the army "for training pilots and conducting aerial experiments" including tests of "a bombsight and bomb-dropping device".
The issue of patent control was correctly seen as critical by the Wrights, and they acquired a wide American patent, intended to give them ownership of basic aerodynamic control. This was fought in both American and European courts. European designers were little affected by the litigation and continued their own development. The legal fight in the U.S. had a crushing effect on the nascent American aircraft industry, and even by the time of America's entry into World War I, in 1917, the U.S. had "only six airplanes, and fourteen trained pilots". The numbers increased substantially over the subsequent years but during the war, all of the fighter aircraft flown by Americans were designed and built in Europe.