The history of aviation spans over two millennia, from the earliest innovations like kites and attempts at tower jumping to supersonic and hypersonic flight in powered, heavier-than-air jet aircraft. Kite flying in China, dating back several hundred years BC, is considered the earliest example of man-made flight. In the 15th-century Leonardo da Vinci designed several flying machines incorporating aeronautical concepts, but they were unworkable due to the limitations of contemporary knowledge. In the late 18th century, the Montgolfier brothers invented the hot-air balloon which soon led to manned flights. At almost the same time, the discovery of hydrogen gas led to the invention of the hydrogen balloon. Various theories in mechanics by physicists during the same period, such as fluid dynamics and Newton's laws of motion, led to the development of modern aerodynamics; most notably by Sir George Cayley. Balloons, both free-flying and tethered, began to be used for military purposes from the end of the 18th century, with France establishing balloon companies during the French Revolution. In the 19th century, especially the second half, experiments with gliders provided the basis for learning the dynamics of winged aircraft; most notably by Cayley, Otto Lilienthal, and Octave Chanute. By the early 20th century, advances in engine technology and aerodynamics made controlled, powered, manned heavier-than-air flight possible for the first time. In 1903, following their pioneering research and experiments with wing design and aircraft control, the Wright brothers successfully incorporated all of the required elements to create and fly the first aeroplane. The basic configuration with its characteristic cruciform tail was established by 1909, followed by rapid design and performance improvements aided by the development of more powerful engines. The first vessels of the air were the rigid steerable balloons pioneered by Ferdinand von Zeppelin that became synonymous with airships and dominated long-distance flight until the 1930s, when large flying boats became popular for trans-oceanic routes. After World War II, the flying boats were in turn replaced by airplanes operating from land, made far more capable first by improved propeller engines, then by jet engines, which reshaped both civilian air travel and military aviation. In the latter half of the 20th century, the development of digital electronics led to major advances in flight instrumentation and "fly-by-wire" systems. The 21st century has seen the widespread use of pilotless drones for military, commercial, and recreational purposes. With computerized controls, inherently unstable aircraft designs, such as flying wings, have also become practical.
Etymology The term aviation, is a noun of action from the stem of Latin avis "bird" with the suffix -ation meaning action or progress. It was coined in 1863 by French pioneer Guillaume Joseph Gabriel de La Landelle (1812–1886) in Aviation ou Navigation aérienne sans ballons.
Beginnings
Tower jumping
Since ancient times, there have been stories of men strapping birdlike wings, stiffened cloaks, or other devices to themselves and attempting to fly, typically by jumping off a tower. The Greek legends of Daedalus and Icarus are some of the earliest known. Others originated in ancient Asia and in the Mediterranean world during the Middle Ages. During this early period, the concepts of lift, stability, and control were not well understood, and most attempts resulted in serious injuries or death. The Andalusian Berber scientist Abbas ibn Firnas (810–887 AD) attempted to fly in Córdoba, Spain, by covering his body with vulture feathers and attached two wings to his arms. The 17th-century Algerian historian Ahmed Mohammed al-Maqqari, quoting a poem by Muhammad I of Córdoba's 9th-century court poet Mu'min ibn Said, recounts that Firnas flew some distance before landing with some injuries, attributed to his lacking a tail (as birds use them to land). In the 12th century, William of Malmesbury wrote that Eilmer of Malmesbury, an 11th-century Benedictine monk, attached wings to his hands and feet and flew a short distance, but broke both legs while landing, also having neglected to make himself a tail. Many others made well-documented jumps in the following centuries. As late as 1811, Albrecht Berblinger constructed an ornithopter and jumped into the Danube at Ulm.
Kites
The kite may have been the first form of man-made heavier-than-air aircraft. It was invented in China possibly as far back as the 5th century BC. by Mozi (Mo Di) and Lu Ban (Gongshu Ban). Evidence to support this finding stands with materials commonly found and ideal for kite building located in China. These are materials such as "silk fabric for sail material, fine, high-tensile-strength silk for flying line, and resilient bamboo for…framework" The reason these materials were so perfect for building kites is largely due to the structure of the materials themselves. Bamboo being a strong, hollow material, largely resembled the hollow bones in birds, which allow for less weight, making flight easier. Some kites were fitted with strings and whistles to make musical sounds while flying. Ancient and mediaeval Chinese sources describe kites being used to measure distances, test the wind, lift men, signal, and communicate and send messages. Later designs often depicted images of flying insects, birds, and other beasts, both real and mythical. Kites spread from China around the world. After being introduced into the rest of Asia, the kite further evolved into the fighter kite, which has an abrasive line used to cut down other kites. The most notable fighter kite designs originated in India and Japan
Man-lifting kites Man-lifting kites are believed to have been used extensively in ancient China for civil and military purposes and sometimes enforced as a punishment. An early recorded flight was that of the prisoner Yuan Huangtou, a Chinese prince, in the 6th century AD. Stories of man-lifting kites can be found in Japan, following the introduction of the kite from China around the seventh century AD. For a period, there was a Japanese law against man-carrying kites.
Rotor wings The use of a rotor for vertical flight has existed since 400 BC in the form of the bamboo-copter, an ancient Chinese toy. The similar "moulinet à noix" (rotor on a nut) appeared in Europe in the 14th century AD.
Hot air balloons
Since ancient times, the Chinese understood that hot air rises and applied the principle to a type of small hot air balloon called a sky lantern. A sky lantern consists of a paper balloon under or just inside which a small lamp is placed. Sky lanterns are traditionally launched for recreation and during festivals. According to Joseph Needham, such lanterns were found in China since the 3rd century BC. Their military use is attributed to the general Zhuge Liang (180–234 AD), who is said to have used them to scare the enemy troops. There is evidence that the Chinese also "solved the problem of aerial navigation" using balloons, hundreds of years before the 18th century.
Renaissance
Eventually, some investigators began to discover and define some of the basics of rational aircraft design. Most notable of these was Leonardo da Vinci, although his work remained unknown until 1797, and so had no influence on developments over the next three hundred years. While his designs are rational, they are not scientific. He particularly underestimated the amount of power that would be needed to propel a flying object, basing his designs on the flapping wings of a bird rather than an engine-powered propeller. Leonardo studied bird and bat flight, claiming the superiority of the latter owing to its unperforated wing. He analyzed these and anticipated many principles of aerodynamics. He understood that "An object offers as much resistance to the air as the air does to the object." Isaac Newton later defined this as the third law of motion in 1687. From the last years of the 15th century until 1505, Leonardo wrote about and sketched many designs for flying machines and mechanisms, including ornithopters, fixed-wing gliders, rotorcraft (perhaps inspired by whirligig toys), parachutes (in the form of a wooden-framed pyramidal tent) and a wind speed gauge. His early designs were man-powered and included ornithopters and rotorcraft; however, he came to realise the impracticality of this and later turned to controlled gliding flight, also sketching some designs powered by a spring. In an essay titled Sul volo (On flight), Leonardo describes a flying machine called "the bird" which he built from starched linen, leather joints, and raw silk thongs. In the Codex Atlanticus, he wrote, "Tomorrow morning, on the second day of January 1496, I will make the thong and the attempt." According to one commonly repeated, albeit presumably fictional story, in 1505 Leonardo or one of his pupils attempted to fly from the summit of Monte Ceceri.
Lighter than air
Beginnings of modern theories Francesco Lana de Terzi proposed in Prodromo dell'Arte Maestra (1670) that large vessels could float in the atmosphere by applying the principles of a vacuum. Lana designed an airship with four huge copper foil spheres connected to support a rider's basket, a tail, and a steering rudder. Critics argued that the thin copper spheres could not sustain ambient air pressure, and further experiments proved that his idea was impossible. Using a vacuum to create lift is called a vacuum airship, but it is still impossible to build with the materials available today. In 1709, Bartolomeu de Gusmão approached King John V of Portugal and claimed to have discovered a way for airborne flight. Due to the King's illness, Gusmão's experiment was rescheduled from its initial 24 June 1709, date to 8 August. The experiment was carried out in front of the king and other nobles in the Casa da India yard, but the paper ship or device burned down before it could take flight.
Balloons
In France, five aviation firsts were accomplished between 4 June and 1 December 1783:
On 4 June, a crowd gathered in Annonay, France, to witness the unmanned hot air balloon display by the Montgolfier brothers. Their 500-pound balloon ascended to nearly 3,000 feet and traveled over a mile and a half. It stayed in the air for ten minutes before tipping over and catching fire. On 27 August, Jacques Charles and the Robert brothers launched the first unmanned hydrogen balloon from Paris' Champ de Mars. It landed almost an hour later in Gonesse, where terrified farmers mistook it for a monster and destroyed it. On 19 October, in front of 2,000 spectators, Jean-François Pilâtre de Rozier and the Marquis d'Arlandes boarded the Montgolfier aircraft as the first people. Later that day, Giroud de Villette, another pilot, took to the skies much higher. On 21 November, the Montgolfiers launched the first free flight with human passengers. King Louis XVI had originally decreed that condemned criminals would be the first pilots, but Jean-François Pilâtre de Rozier, along with the Marquis François d'Arlandes, successfully petitioned for the honour. They drifted 8 km (5.0 mi) in a balloon powered by a wood fire. On 1 December, Jacques Charles and the Nicolas-Louis Robert launched their manned hydrogen balloon from the Jardin des Tuileries in Paris, as a crowd of 400,000 witnessed. They ascended to a height of about 1,800 feet (550 m)[15] and landed at sunset in Nesles-la-Vallée after a flight of 2 hours and 5 minutes, covering 36 km. After Robert alighted, Charles decided to ascend alone. This time he ascended rapidly to an altitude of about 9,800 feet (3,000 m), where he saw the sun again, suffered extreme pain in his ears, and never flew again. Ballooning became a major interest in Europe in the late 18th century, providing the first detailed understanding of the relationship between altitude and the atmosphere. Non-steerable balloons were employed during the American Civil War by the Union Army Balloon Corps. The young Ferdinand von Zeppelin first flew as a balloon passenger with the Union Army of the Potomac in 1863. In the early 1900s, ballooning was a popular sport in Britain. These privately owned balloons usually used coal gas as the lifting gas. This has half the lifting power of hydrogen so the balloons had to be larger, however, coal gas was far more readily available and the local gas works sometimes provided a special lightweight formula for ballooning events.
Airships
Airships were originally called "dirigible balloons" and are still sometimes called dirigibles today. Work on developing a steerable (or dirigible) balloon continued sporadically throughout the 19th century. The first powered, controlled, sustained lighter-than-air flight is believed to have taken place in 1852 when Henri Giffard flew 15 miles (24 km) in France, with a steam engine-driven craft. Another advancement was made in 1884, when the first fully controllable free-flight was made in a French Army electric-powered airship, La France, by Charles Renard and Arthur Krebs. The 170-foot (52 m) long, 66,000-cubic-foot (1,900 m3) airship covered 8 km (5.0 mi) in 23 minutes with the aid of an 8½ horsepower electric motor. However, these aircraft were generally short-lived and extremely frail. Routine, controlled flights did not occur until the advent of the internal combustion engine.
The first aircraft to make routine controlled flights were non-rigid airships (sometimes called "blimps".) The most successful early pioneering pilot of this type of aircraft was the Brazilian Alberto Santos-Dumont who effectively combined a balloon with an internal combustion engine. On 19 October 1901, he flew his airship Number 6 over Paris from the Parc de Saint Cloud around the Eiffel Tower and back in under 30 minutes to win the Deutsch de la Meurthe prize. Santos-Dumont went on to design and build several aircraft. The subsequent controversy surrounding his and others' competing claims with regard to aircraft overshadowed his great contribution to the development of airships. At the same time that non-rigid airships were starting to have some success, the first successful rigid airships were also being developed. These were far more capable than fixed-wing aircraft in terms of pure cargo-carrying capacity for decades. Rigid airship design and advancement was pioneered by the German count Ferdinand von Zeppelin. Construction of the first Zeppelin airship began in 1899 in a floating assembly hall on Lake Constance in the Bay of Manzell, Friedrichshafen. This was intended to ease the starting procedure, as the hall could easily be aligned with the wind. The prototype airship LZ 1 (LZ for "Luftschiff Zeppelin") had a length of 128 m (420 ft), was driven by two 10.6 kW (14.2 hp) Daimler engines and balanced by moving a weight between its two nacelles. Its first flight, on 2 July 1900, lasted for only 18 minutes, as LZ 1 was forced to land on the lake after the winding mechanism for the balancing weight had broken. Upon repair, the technology proved its potential in subsequent flights, bettering the 6 m/s speed attained by the French airship La France by 3 m/s, but could not yet convince possible investors. It was several years before the Count was able to raise enough funds for another try. The German airship passenger service known as DELAG (Deutsche-Luftschiffahrts AG) was established in 1910. Although airships were used in both World War I and II, and continue on a limited basis to this day, their development has been largely overshadowed by heavier-than-air craft.
Heavier than air
17th and 18th centuries Traveller Evliya Çelebi reported that in 1633, Ottoman scientist and engineer Lagari Hasan Çelebi blasted off from Sarayburnu in a 7-winged rocket propelled by 50 okka (140 lbs) of gunpowder. The flight was said to have been undertaken at the time of the birth of Sultan Murad IV's daughter. As Evliya Celebi wrote, Lagari proclaimed before launching his craft "O my sultan! Be blessed, I am going to talk to Jesus!"; after ascending in the rocket, he landed in the sea, swimming ashore and joking "O my sultan! Jesus sends his regards to you!"; he was rewarded by the Sultan with silver and the rank of sipahi in the Ottoman army. Evliya Çelebi also wrote of Lagari's brother, Hezârfen Ahmed Çelebi, making a flight by glider a year earlier. Italian inventor Tito Livio Burattini, invited by the Polish King Władysław IV to his court in Warsaw, built a model aircraft with four fixed glider wings in 1647. Described as "four pairs of wings attached to an elaborate 'dragon'", it was said to have successfully lifted a cat in 1648 but not Burattini himself. He promised that "only the most minor injuries" would result from landing the craft. His "Dragon Volant" is considered "the most elaborate and sophisticated aeroplane to be built before the 19th Century". The first published paper on aviation was "Sketch of a Machine for Flying in the Air" by Emanuel Swedenborg published in 1716. This flying machine consisted of a light frame covered with strong canvas and provided with two large oars or wings moving on a horizontal axis, arranged so that the upstroke met with no resistance while the downstroke provided lifting power. Swedenborg knew that the machine would not fly, but suggested it as a start and was confident that the problem would be solved. Swedenborg proved prescient in his observation that a method of powering of an aircraft was one of the critical problems to be overcome.
It seems easier to talk of such a machine than to put it into actuality, for it requires greater force and less weight than exists in a human body. The science of mechanics might perhaps suggest a means, namely, a strong spiral spring. If these advantages and requisites are observed, perhaps in time to come someone might know how better to utilise our sketch and cause some addition to be made so as to accomplish that which we can only suggest. Yet there are sufficient proofs and examples from nature that such flights can take place without danger, although when the first trials are made you may have to pay for the experience, and not mind an arm or leg. On 16 May 1793, Spanish inventor Diego Marín Aguilera crossed the river Arandilla in Coruña del Conde, Castile, flying 300 to 400 metres (980 to 1,310 ft) with a flying machine.
19th century Balloon jumping replaced tower jumping, also demonstrating with typically fatal results that man-power and flapping wings were useless in achieving flight. At the same time scientific study of heavier-than-air flight began in earnest. In 1801, the French officer André Guillaume Resnier de Goué managed a 300-metre glide by starting from the top of the city walls of Angoulême and he broke one leg on arrival. In 1837, French mathematician and brigadier general Isidore Didion stated, "Aviation will be successful only if one finds an engine whose ratio with the weight of the device to be supported will be larger than current steam machines or the strength developed by humans or most of the animals".
George Cayley and the first modern aircraft George Cayley was first called the "father of the aeroplane" in 1846. During the last years of the 18th century, he had begun the first rigorous study of the physics of flight and would later design the first modern heavier-than-air craft. Among his many achievements, his most important contributions to aeronautics include:
Clarifying our ideas and laying down the principles of heavier-than-air flight. Reaching a scientific understanding of the principles of bird flight. Scientific aerodynamic experiments were conducted to demonstrate drag and streamlining, movement of the center of pressure, and the increase in lift from curving the wing surface. Defining the modern aeroplane configuration comprising a fixed-wing, fuselage and tail assembly. Demonstrations of manned, gliding flight. Identified that a lightweight, powerful engine would be necessary for sustained heavier-than-air flight, now known as the power-to-weight ratio Recognized for establishing the theoretical foundation for engine use in airplanes and modern aircraft design by identifying and explaining the four fundamental forces of flight: lift, thrust, drag, and weight. Cayley's research on the aeroplane aimed to address the four fundamental areas that are essential to aeronautics: propulsion, structural design, aerodynamics, and stability and control. His work laid the groundwork for a comprehensive understanding of these critical components, which continue to be vital in the field today. Cayley's first innovation was to study the basic science of lift by adopting the whirling arm test rig for use in aircraft research and using simple aerodynamic models on the arm, rather than attempting to fly a model of a complete design. In 1799, he set down the concept of the modern aeroplane as a fixed-wing flying machine with separate systems for lift, propulsion, and control. In 1804, Cayley constructed a model glider, which was the first modern heavier-than-air flying machine. It had the layout of a conventional modern aircraft, with an inclined wing towards the front and an adjustable tail at the back with both tailplane and fin. A movable weight allowed adjustment of the model's centre of gravity. In 1809, goaded by the farcical antics of his contemporaries, he began the publication of a landmark three-part treatise titled "On Aerial Navigation" (1809–1810). In it he wrote the first scientific statement of the problem, "The whole problem is confined within these limits, viz. to make a surface support a given weight by the application of power to the resistance of air". He identified the four vector forces that influence an aircraft: thrust, lift, drag and weight and distinguished stability and control in his designs. He also identified and described the importance of the cambered aerofoil, dihedral, diagonal bracing and drag reduction, and contributed to the understanding and design of ornithopters and parachutes. In 1848, he had progressed far enough to construct a glider in the form of a triplane large and safe enough to carry a child. A local boy was chosen; his name is unknown. He went on to publish in 1852 the design for a full-size manned glider or "governable parachute" to be launched from a balloon. He then constructed a version capable of launching from the top of a hill, which carried the first adult aviator across Brompton Dale in 1853.
Age of steam
Drawing directly from Cayley's work, Henson's 1842 design for an aerial steam carriage broke new ground. Although only a design, it was the first in history for a propeller-driven fixed-wing aircraft.
1866 saw the founding of the Aeronautical Society of Great Britain and two years later the world's first aeronautical exhibition was held at the Crystal Palace, London, where John Stringfellow was awarded a £100 prize for the steam engine with the best power-to-weight ratio. In 1848, Stringfellow achieved the first powered flight using an unmanned 10 feet (3.0 m) wingspan steam-powered monoplane built in a disused lace factory in Chard, Somerset. Employing two contra-rotating propellers on the first attempt, made indoors, the machine flew ten feet before becoming destabilised, damaging the craft. The second attempt was more successful, the machine leaving a guidewire to fly freely, achieving thirty yards of straight and level powered flight. Francis Herbert Wenham presented the first paper to the newly formed Aeronautical Society (later the Royal Aeronautical Society), On Aerial Locomotion. He advanced Cayley's work on cambered wings, making important findings. To test his ideas, from 1858 he had constructed several gliders, both manned and unmanned, and with up to five stacked wings. He realised that long, thin wings are better than bat-like ones because they have more leading edge for their area. Today this relationship is known as the aspect ratio of a wing. The latter part of the 19th century became a period of intense study, characterized by the "gentleman scientists" who represented most research efforts until the 20th century. Among them was the British scientist-philosopher and inventor Matthew Piers Watt Boulton, who studied lateral flight control and was the first to patent an aileron control system in 1868. In 1871, Wenham made the first wind tunnel using a fan, driven by a steam engine, to propel air down a 12 ft (3.7 m) tube to the model.
Meanwhile, the British advances had galvanised French researchers. In 1857, Félix du Temple proposed a monoplane with a tailplane and retractable undercarriage. Developing his ideas with a model powered first by clockwork and later by steam, he eventually achieved a short hop with a full-size manned craft in 1874. It achieved lift-off under its own power after launching from a ramp, glided for a short time and returned safely to the ground, making it the first successful powered glide in history. In 1865, Louis Pierre Mouillard published an influential book The Empire Of The Air (l'Empire de l'Air).
In 1856, Frenchman Jean-Marie Le Bris made the first flight higher than his point of departure, by having his glider "L'Albatros artificiel" pulled by a horse on a beach. He reportedly achieved a height of 100 metres, over a distance of 200 metres.
Alphonse Pénaud, a Frenchman, advanced the theory of wing contours and aerodynamics. He also constructed successful models of aeroplanes, helicopters and ornithopters. In 1871 he flew the first aerodynamically stable fixed-wing aeroplane, a model monoplane he called the "Planophore", a distance of 40 m (130 ft). Pénaud's model incorporated several of Cayley's discoveries, including the use of a tail, wing dihedral for inherent stability, and rubber power. The planophore also had longitudinal stability, being trimmed such that the tailplane was set at a smaller angle of incidence than the wings, an original and important contribution to the theory of aeronautics. Pénaud's later project for an amphibian aeroplane, although never built, incorporated other modern features. A tailless monoplane with a single vertical fin and twin tractor propellers, it also featured hinged rear elevator and rudder surfaces, retractable undercarriage and a fully enclosed, instrumented cockpit.
Another theorist was Frenchman Victor Tatin. In 1879, he flew a model which, like Pénaud's project, was a monoplane with twin tractor propellers but also had a separate horizontal tail. It was powered by compressed air. Flown tethered to a pole, this was the first model to take off under its own power. In 1884, Alexandre Goupil published his work La Locomotion Aérienne (Aerial Locomotion), although the flying machine he later constructed failed to fly.
In 1890, the French engineer Clément Ader completed the first of three steam-driven flying machines, the Éole. On 9 October 1890, Ader made an uncontrolled hop of around 50 metres (160 ft); this was the first manned aeroplane to take off under its own power. His Avion III of 1897, notable only for having twin steam engines, failed to fly: Ader later claimed success and was not debunked until 1910 when the French Army published its report on his attempt.
Hiram Maxim was an American engineer who had moved to England. He built his own whirling arm rig and wind tunnel and constructed a large machine with a wingspan of 105 feet (32 m), a length of 145 feet (44 m), fore and aft horizontal surfaces and a crew of three. Twin propellers were powered by two lightweight compound steam engines each delivering 180 hp (130 kW). The overall weight was 8,000 pounds (3,600 kg). It was intended as a test rig to investigate aerodynamic lift; because it lacked flight controls it ran on rails, with a second set of rails above the wheels to restrain it. Completed in 1894, on its third run it broke from the rail, became airborne for about 200 yards at two to three feet of altitude and was badly damaged upon falling back to the ground. It was subsequently repaired, but Maxim abandoned his experiments shortly afterwards.
Manned gliders and Otto Lilienthal
Around the last decade of the 19th century, a number of key figures were refining and defining the modern aeroplane. Lacking a suitable engine, aircraft work focused on stability and control in gliding flight. In 1879, Biot constructed a bird-like glider with the help of Massia and flew in it briefly. It is preserved in the Musee de l'Air, France, and is claimed to be the earliest man-carrying flying machine still in existence. The Englishman Horatio Phillips made key contributions to aerodynamics. He conducted extensive wind tunnel research on aerofoil sections, proving the principles of aerodynamic lift foreseen by Cayley and Wenham. His findings underpin all modern aerofoil design. Between 1883 and 1886, the American John Joseph Montgomery developed a series of three manned gliders, before conducting his own independent investigations into aerodynamics and circulation of lift.
Otto Lilienthal became known as the "Glider King" or "Flying Man" of Germany. He duplicated Wenham's work and greatly expanded on it in 1884, publishing his research in 1889 as Birdflight as the Basis of Aviation (Der Vogelflug als Grundlage der Fliegekunst), which is seen as one of the most important works in aviation history. He also produced a series of hang gliders, including bat-wing, monoplane, and biplane forms, such as the Derwitzer Glider and Normal soaring apparatus, which is considered to be the first airplane in series production, making the "Maschinenfabrik Otto Lilienthal" the first airplane production company in the world. Starting in 1891, he became the first person to make controlled untethered glides routinely, and the first to be photographed flying a heavier-than-air machine, stimulating interest around the world. Lilienthal's work led to him developing the concept of the modern wing. His flights in the year 1891 are seen as the beginning of human flight and because of that he is often referred to as either the "father of aviation" or "father of flight". He rigorously documented his work, including photographs, and for this reason is one of the best known of the early pioneers. Lilienthal made over 2,000 glider flights until his death in 1896 from injuries sustained in a glider crash. Picking up where Lilienthal left off, Octave Chanute took up aircraft design after an early retirement, and funded the development of several gliders. In the summer of 1896, his team flew several of their designs eventually deciding that the best was a biplane design. Like Lilienthal, he documented and photographed his work. In Britain Percy Pilcher, who had worked for Maxim, built and successfully flew several gliders during the mid to late 1890s. The invention of the box kite during this period by the Australian Lawrence Hargrave led to the development of the practical biplane. In 1894, Hargrave linked four of his kites together, added a sling seat, and was the first to obtain lift with a heavier than air aircraft, when he flew up 16 feet (4.9 m). Later pioneers of manned kite flying included Samuel Franklin Cody in England and Captain Génie Saconney in France. William Frost from Pembrokeshire, Wales started his project in 1880 and after 16 years, he designed a flying machine and in 1894 won a patent for a "Frost Aircraft Glider". Reports say witnesses claimed the craft flew at Saundersfoot in 1896, travelling 500 yards before colliding with a tree and falling in a field.
Langley
After a distinguished career in astronomy and shortly before becoming Secretary of the Smithsonian Institution, Samuel Pierpont Langley started a serious investigation into aerodynamics at what is today the University of Pittsburgh. In 1891, he published Experiments in Aerodynamics detailing his research, and then turned to building his designs. He hoped to achieve automatic aerodynamic stability, so he gave little consideration to in-flight control. On 6 May 1896, Langley's Aerodrome No. 5 made the first successful sustained flight of an unpiloted, engine-driven heavier-than-air craft of substantial size. It was launched from a spring-actuated catapult mounted on top of a houseboat on the Potomac River near Quantico, Virginia. Two flights were made that afternoon, one of 1,005 metres (3,297 ft) and a second of 700 metres (2,300 ft), at a speed of approximately 25 miles per hour (40 km/h). On both occasions, the Aerodrome No. 5 landed in the water as planned, because, in order to save weight, it was not equipped with landing gear. On 28 November 1896, another successful flight was made with the Aerodrome No. 6. This flight, of 1,460 metres (4,790 ft), was witnessed and photographed by Alexander Graham Bell. The Aerodrome No. 6 was actually Aerodrome No. 4 greatly modified. So little remained of the original aircraft that it was given a new designation. With the successes of the Aerodrome No. 5 and No. 6, Langley started looking for funding to build a full-scale man-carrying version of his designs. Spurred by the Spanish–American War, the U.S. government granted him $50,000 to develop a man-carrying flying machine for aerial reconnaissance. Langley planned on building a scaled-up version known as the Aerodrome A, and started with the smaller Quarter-scale Aerodrome, which flew twice on 18 June 1901, and then again with a newer and more powerful engine in 1903. With the basic design apparently successfully tested, he then turned to the problem of a suitable engine. He contracted Stephen Balzer to build one, but was disappointed when it delivered only 8 hp (6.0 kW) instead of the 12 hp (8.9 kW) he expected. Langley's assistant, Charles M. Manly, then reworked the design into a five-cylinder water-cooled radial that delivered 52 hp (39 kW) at 950 rpm, a feat that took years to duplicate. Now with both power and a design, Langley put the two together with great hopes. To his dismay, the resulting aircraft proved to be too fragile. Simply scaling up the original small models resulted in a design that was too weak to hold itself together. Two launches in late 1903 both ended with the Aerodrome immediately crashing into the water. The pilot, Manly, was rescued each time. Also, the aircraft's control system was inadequate to allow quick pilot responses, and it had no method of lateral control, and the Aerodrome's aerial stability was marginal. Langley's attempts to gain further funding failed, and his efforts ended. Nine days after his second abortive launch on 8 December, the Wright brothers successfully flew their Flyer. Glenn Curtiss made 93 modifications to the Aerodrome and flew this very different aircraft in 1914. Without acknowledging the modifications, the Smithsonian Institution asserted that Langley's Aerodrome was the first machine "capable of flight".
Whitehead
Gustave Weißkopf was a German who emigrated to the U.S., where he soon changed his name to Whitehead. From 1897 to 1915, he designed and built early flying machines and engines. On 14 August 1901, two and a half years before the Wright Brothers' flight, he claimed to have carried out a controlled, powered flight in his Number 21 monoplane at Fairfield, Connecticut. The flight was reported in the Bridgeport Sunday Herald local newspaper. About 30 years later, several people questioned by a researcher claimed to have seen that or other Whitehead flights. In March 2013, Jane's All the World's Aircraft, an authoritative source for contemporary aviation, published an editorial which accepted Whitehead's flight as the first manned, powered, controlled flight of a heavier-than-air craft. The Smithsonian Institution (custodians of the original Wright Flyer) and many aviation historians continue to maintain that Whitehead did not fly as suggested. The historians of the Royal Aeronautical Society noted that: "All available evidence fails to support the claim that Gustave Whitehead made sustained, powered, controlled flights predating those of the Wright brothers." The editors of Scientific American agree: "The data show that not only was Whitehead not first in flight, but that he may never have made a controlled, powered flight at any time."
Pearse
Richard Pearse was a New Zealand farmer and inventor who performed pioneering aviation experiments. Witnesses interviewed many years afterward claimed that Pearse flew and landed a powered heavier-than-air machine on 31 March 1903, nine months before the Wright brothers flew. Documentary evidence for these claims remains open to interpretation and dispute, and Pearse himself never made such claims. In a newspaper interview in 1909, he said he did not "attempt anything practical ... until 1904". If he did fly in 1903, the flight appears to have been poorly controlled in comparison to the Wrights'.
Wright brothers
Using a methodical approach and concentrating on the controllability of the aircraft, the brothers built and tested a series of kite and glider designs from 1898 to 1902 before attempting to build a powered design. The gliders worked, but not as well as the Wrights had expected based on the experiments and writings of their predecessors. Their first full-size glider, launched in 1900, had only about half the lift they anticipated. Their second glider, built the following year, performed even more poorly. Rather than giving up, the Wrights constructed their own wind tunnel and created a number of sophisticated devices to measure lift and drag on the 200 wing designs they tested. As a result, the Wrights corrected earlier mistakes in calculations regarding drag and lift. Their testing and calculating produced a third glider with a higher aspect ratio and true three-axis control. They flew it successfully hundreds of times in 1902, and it performed far better than the previous models. By using a rigorous system of experimentation, involving wind-tunnel testing of airfoils and flight testing of full-size prototypes, the Wrights not only built a working aircraft the following year, the Wright Flyer, but also helped advance the science of aeronautical engineering.
The Wrights appear to be the first to make serious studied attempts to simultaneously solve the power and control problems. Both problems proved difficult, but they never lost interest. They solved the control problem by inventing wing warping for roll control, combined with simultaneous yaw control with a steerable rear rudder. Almost as an afterthought, they designed and built a low-powered internal combustion engine. They also designed and carved wooden propellers that were more efficient than any before, enabling them to gain adequate performance from their low engine power. Although wing-warping as a means of lateral control was used only briefly during the early history of aviation, the principle of combining lateral control in combination with a rudder was a key advance in aircraft control. While many aviation pioneers appeared to leave safety largely to chance, the Wrights' design was greatly influenced by the need to teach themselves to fly without unreasonable risk to life and limb, by surviving crashes. This emphasis, as well as low engine power, was the reason for low flying speed and for taking off in a headwind. Performance, rather than safety, was the reason for the rear-heavy design because the canard could not be highly loaded; anhedral wings were less affected by crosswinds and were consistent with the low yaw stability. According to the Smithsonian Institution and Fédération Aéronautique Internationale (FAI), the Wrights made the first sustained, controlled, powered heavier-than-air manned flight at Kill Devil Hills, North Carolina, four miles (8 km) south of Kitty Hawk, North Carolina on 17 December 1903. The first flight by Orville Wright, of 120 feet (37 m) in 12 secon