Aviation history

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Humanity's desire to fly likely dates to the first time man observed birds, an observation illustrated in the legendary story of Daedalus and Icarus. Daedalus was imprisoned on the island of Crete by king Minos, and so built wings out of feathers and wax for himself and his son. Much of the focus of early research was on imitating birds, but through trial and error, balloons, airships, gliders and eventually aircraft and types of flying machines were invented.

Aircraft designers have struggled to make their planes go faster, fly higher, and be controlled more easily.

• Engines have thus become steadily more compact and more powerful, in a sequence that stretches from steam engines to piston, jet and rocket engines.

• Planes have become more streamlined and their materials stronger and lighter. Initially aircraft were made of canvas and wood but today aircraft are made of aluminium, and increasingly, carbon fiber, which is prized for its light weight and strength.

• The methods used to control planes continue to advance. Initially planes were controlled by moving one's entire body (hang gliders) or warping the planes' wings (Wright brothers). Modern planes are controlled with the help of computers and other electronics, which can, like the brain of a bird, help with stabilizing shapes in flight. (Modern fighterplanes are a good example since they are built to be unstable in flight to let them turn faster).

Contents 1 Before the 20th century 1.1 Lighter than air 1.2 Toward better understanding 1.3 Picking up the pace 2 1900 to 1914 (The "Pioneer Era") 2.1 Lighter than air 2.2 Langley 2.3 The Wright Brothers 2.4 Other early flights 3 1914 - 1918: World War I 4 1918 - 1939 (The "Golden Age") 5 1939-1945: World War II 6 1945 - 1991: The Cold War 7 2001-Future 8 See also 9 External links

[edit] Before the 20th century

See List of early flying machines and First flying machine.

During the 9th century, the Muslim Moors Armen Firman and Abbas Qasim Ibn Firnas are known to have built and flown gliders. Eilmer of Malmesbury did the same in circa 1010, flying over 200 metres, possibly inspired by the description in the story of Daedalus.

Upon visiting China in the 13th century, Marco Polo brought back stories of human-carrying kites (which stay aloft via the wind's power but are tethered to the ground) and flying tops. "Pao Phu Tau" was a 4th century Chinese book containing some ideas related to rotary wing aircraft (helicopters).

Roughly 2 centuries later, in the 15th century renaissance that Polo's journey presaged, Leonardo da Vinci designed an aircraft (a glider -- his drawings still exist). The aircraft was never built by Leonardo but its plans were preserved, and it was constructed in the late 20th century from materials that would have been available to him. The design was deemed flightworthy and the prototype actually flew, but the design was interpreted with modern knowledge of aerodynamic principles. (Leonardo also sketched designs for a helicopter, but this design would not have flown.)

In the 17th century Turkish scientist Lagari Hasan Çelebi launched himself in the air in a rocket, which was composed of a large cage with a conical top filled with gunpowder. The flight was accomplished as a part of celebrations performed for the birth of Ottoman Emperor Murat IV's daughter.

He is believed to have made a soft landing in the Bosporus and was rewarded by the sultan with a valuable military position in the Ottoman army. The flight was estimated to have lasted about twenty seconds and the maximum height reached around 300 metres.

In 1638, his brother, Hezarfen Ahmet Celebi used wings of his design to fly across the Bosphorus. He jumped off the Galata Tower (55m high) in Europe, flew a distance of about 3km, and landed on the Asian side, uninjured.

[edit] Lighter than air

Although many people think of human flight as beginning with the aircraft in the early 1900's, in fact people had already been flying for some 200 years.

The first generally recognized human flight took place in Paris in 1783. Jean-François Pilâtre de Rozier and Francois d'Arlandes went 5 miles (8 km) in a hot air balloon invented by the Montgolfier brothers. The balloon was powered by a wood fire, and was not steerable: that is, it flew wherever the wind took it.

Ballooning became a major "rage" in Europe in the late 18th century, providing the first detailed understanding of the relationship between altitude and the atmosphere.

Work on developing a steerable (or dirigible) balloon (now called an airship) continued sporatically throughout the 1800's. The first powered, controlled, sustained lighter-than-air flight is generally believed to have taken place in 1852 when Henri Giffard flew 15 miles (24 km) in France, with a steam engine driven craft.

Another notable advance 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 long , 66,000 cubic foot airship covered 8 km (5 miles) in 23 minutes with the aid of an 8-1/2 horsepower electric motor.

However, these aircraft were generally short-lived and extremely frail. Routine, controlled flights would not come to pass until the advent of the internal combustion engine (see below.)

Although airships were used in both WWI, and WWII, and continue on a limited basis to this day, their development has been largely overshadowed by heavier-than-air craft.

[edit] Toward better understanding

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. He said, "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 some one might know how better to utilize 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." Swedenborg would prove prescient in his observation that powering the aircraft through the air was the crux of flying.

During the last years of the 18th century, Sir George Cayley started the first rigorous study of the physics of flight. In 1799 he exhibited a plan for a glider, which except for planform was completely modern in having a separate tail for control and having the pilot suspended below the center of gravity to provide stability, and flew it as a model in 1804. Over the next five decades Cayley worked on and off on the problem, during which he invented most of basic aerodynamics and introduced such terms as lift and drag. He used both internal and external combustion engines, fueled by gunpowder, but it was left to Alphonse Penaud to make powering models simple, with rubber power. Later Cayley turned his research to building a full-scale version of his design, first flying it unmanned in 1849, and in 1853 his coachman made a short flight at Brompton, near Scarborough in Yorkshire.

In 1848, John Stringfellow had a successful test flight of a steam-powered model, in Chard, Somerset, England. This was 'unmanned'.

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 meters, over a distance of 200 meters.

In 1874, Félix du Temple built the "Monoplane", a large plane made of aluminium in Brest, France, with a wingspan of 13 meters and a weight of only 80 kilograms (without the driver). Several trials were made with the plane, and it is generally recognized that it achieved lift off under its own power after a ski-jump run, glided for a short time and returned safely to the ground, making it the first successful powered flight in history, although the flight was only a short distance and a short time.

Another person who advanced the art of flying was Frank Wenham, who unsuccessfully attempted to build a series of unmanned gliders. During his work he found that the majority of the lift from a bird-like wing appeared to be generated at the front, and concluded that long, thin wings would be better than the bat-like ones suggested by many, because they would have more leading edge for their weight. Today this measure is known as aspect ratio. He presented a paper on his work to the newly formed Royal Aeronautical Society of Great Britain in 1866, and decided to prove it by building the world's first wind tunnel in 1871. Members of the Society used the tunnel and were learnt that cambered wings generated considerably more lift than expected by Cayley's Newtonian reasoning, with lift-to-drag ratios of about 5:1 at 15 degrees. This clearly demonstrated the ability to build practical heavier-than-air flying machines; what remained was the problem of powering them, and controlling the flight.

[edit] Picking up the pace

The 1880s became a period of intense study, characterized by the "gentleman scientists" who represented most research efforts until the 20th century. Starting in the 1880s advancements were made in construction that led to the first truly practical gliders. Three people in particular were active: Otto Lilienthal, Percy Pilcher and Octave Chanute. One of the first truly modern gliders appears to have been built by John J. Montgomery; it flew in a controlled manner outside of San Diego on August 28, 1883. It was not until many years later that his efforts became well known. Another delta hang-glider had been constructed by Wilhelm Kress as early as 1877 near Vienna.

Otto Lilienthal of Germany duplicated Wenham's work and greatly expanded on it in 1874, publishing all of his research in 1889. He also produced a series of ever-better gliders, and in 1891 was able to make flights of 25 meters or more routinely. He rigorously documented his work, including photographs, and for this reason is one of the best known of the early pioneers. He also promoted the idea of "jumping before you fly", suggesting that researchers should start with gliders and work their way up, instead of simply designing a powered machine on paper and hoping it would work. His type of aircraft is now know as a hang glider.

Lilienthal knew that once an engine was attached to the plane it would be nearly impossible to further study the laws of aviation. The finding and describing of many of those laws were his greatest heritage to his successors, as they were able to construct their planes accordingly and thereby save themselves years of trial and error.

By the time of his death in 1896 he had made 2500 flights on a number of designs, when a gust of wind broke the wing of his latest design, causing him to fall from a height of roughly 56 ft (17 m), fracturing his spine. He died the next day, with his last words being "sacrifices must be made". Lilienthal had been working on small engines suitable for powering his designs at the time of his death.

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 troop flew several of their designs many times at Miller Beach, Indiana, eventually deciding that the best was a biplane design that looks surprisingly modern. Like Lilienthal, he heavily documented his work while photographing it, and was busy corresponding with like-minded hobbyists around the world. Chanute was particularly interested in solving the problem of natural stability of the aircraft in flight, one which birds corrected for by instinct, but one that humans would have to do manually. The most disconcerting problem was longitudinal stability, because as the angle of attack of a wing increased, the center of pressure moved forward and made the angle increase more. Without immediate correction, the craft would pitch up and stall.

Throughout this period, a number of attempts were made to produce a true powered aircraft. However the majority of these efforts were doomed to failure, being designed by hobbyists who did not have a full understanding of the problems being discussed by Lilienthal and Chanute.

In France Clément Ader successfully launched his steam powered Eole for a short 50 meter flight near Paris in 1890, making it the first self-propelled "long distance" flight in history. After this test he immediately turned to a larger design, which took five years to build. However, this design, the Avion III, was too heavy and was barely able to leave the ground. The plane reportedly managed to fly a distance of 300 meters, at a small height.

Sir Hiram Maxim studied a series of designs in England, eventually building a monstrous 7,000 lb (3,175 kg) design with a wingspan of 105 feet (32 m), powered by two advanced low-weight steam engines which delivered 180 hp (134 kW) each. Maxim built it to study the basic problems of construction and power and it remained without controls, and, realizing that it would be unsafe to fly, he instead had a 1,800 foot (550 m) track constructed for test runs. After a number of test runs working out problems, on July 31, 1894 they started a series of runs at increasing power settings. The first two were successful, with the craft "flying" on the rails. In the afternoon the crew of three fired the boilers to full power, and after reaching over 42 mph (68 km/h) about 600 ft (180 m) down the track the machine produced so much lift it pulled itself free of the track and crashed after flying at low altitudes for about 200 feet (60 m). Declining fortunes left him unable to continue his work until the 1900s, when he was able to test a number of smaller designs powered by gasoline.

Another successful early experimenter was Samuel Pierpont Langley. After a distinguished career in astronomy and a tenure at the Smithsonian Institution, 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. On May 6, 1896, his Aerodrome No. 5 made the first fully successful flight of a powered heavier-than-air craft of substantial size, flying twice with one flight of 3,300 ft (1,000 m) and a second of 2,300 ft (700 m), at about 25 mph (40 km/h). On November 28, another successful flight was made with a similar model, the Aerodrome No.6. It flew a distance of approximately 1,460 m (4,790 ft).

In the United Kingdom an attempt at heavier-than-air flight was made by the aviation pioneer Percy Pilcher. Pilcher had built several working gliders, The Bat, The Beetle, The Gull and The Hawk, which he flew successfully during the mid to late 1890s. In 1899 he constructed a prototype powered aircraft which, recent research has shown, would have been capable of flight. However, he died in a glider accident before he was able to test it, and his plans were forgotten for many years.

[edit] 1900 to 1914 (The "Pioneer Era")

[edit] Lighter than air

The first aircraft to make routine controlled flights were non-rigid airships (later called "blimps".) The most successful early pioneer of this type of aircraft was the Brazilian Alberto Santos-Dumont. Santos-Dumont effectively combined a balloon with an internal combustion engine. On October 19, 1901 he became world famous when he flew his airship "Number 6" over Paris from the Parc Saint Cloud around the Eiffel Tower and back in under thirty minutes to win the Deutsch de la Meurthe prize. After this triumph in airships, Santos-Dumont would go on to design and build several aircraft. The subsequent controversy surrounding his and others' competing claims with regard to aircraft would come to overshadow and obscure his unparalleled contributions to the development of airships.

At the same time that non-rigid airships were starting to have some success, rigid airships were also becoming more advanced. Indeed, rigid body dirigibles would be far more capable than fixed wing aircraft in terms of pure cargo carrying capacity for decades. Dirigible design and advancement was brought about 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, was driven by two 14.2 ps (10.6 kW) Daimler engines and balanced by moving a weight between its two nacelles.

The first Zeppelin flight occurred on July 2, 1900. It 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, beating the 6 m/s velocity record of French airship La France by 3 m/s, but could not yet convince possible investors. It would be several years before the Count was able to raise enough funds for another try. See the zeppelin page for more history.

[edit] Langley

With the success of the Aerodrome No. 5 and its follow-on No. 6, Langley started looking for funding to build a full-scale man-carrying version of his designs. He succeeded in winning $50,000 in funding from the government, perhaps spurred on by the recent opening of the Spanish-American War. 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 June 18, 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 him one, but was disappointed when it delivered only 8 horsepower (6 kW) instead of 12 hp (9 kW) as he expected. Langley's assistant, Charles M. Manly, then reworked the design into a five-cylinder water-cooled radial that delivered 52 horsepower (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. He had apparently overlooked the effects of minimum gauge, and simply scaling up the original small models resulted in a design that was too heavy to hold itself up. Two launches in late 1903 both ended with the Aerodrome crashing into the water almost immediately after launch.

His attempts to gain further funding failed, and his efforts ended -- only weeks later the Wright brothers successfully flew their aptly-named Flyer.

(Glenn Curtiss made several modifications to the Aerodrome and successfully flew it in 1914 -- the Smithsonian Institution thus continued to boast that Langley's Aerodrome was the first machine "capable of flight".)

[edit] The Wright Brothers

Following Lilienthal's principles of jumping before flying, the brothers built and tested a series of kite and glider designs from 1900 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 19th century predecessors. Their first 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, though they missed the effect of Reynolds number (known since 1883), which would have given them an even bigger advantage. Their testing and calculating produced a third glider design, which they flew in 1902. It performed far better than the previous models. In the end, by establishing their rigorous system of designing, wind-tunnel testing of models and flight testing of full-size prototypes, the Wrights not only built a working aircraft but also helped advance the modern science of aeronautical engineering.

The Wrights appear to be the first design team to make serious studied attempts to simultaneously solve the power and control problems. Both problems proved difficult, but they never lost interest. Eventually, they designed and built an engine that could provide the needed power, and solved the control problem through a system known as "wing warping". Although this method was used only briefly during the history of aviation, it worked at the low airspeeds their designs would fly at, and proved to be a key advance, leading directly to modern ailerons. 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, not lack of power, was the reason for the low speed and for taking off in a head wind. It was also the reason for the rear-heavy design, for the canard, and for the anhedral wings.

The Wrights made the first sustained, controlled and powered heavier-than-air flight at Kill Devil Hills, North Carolina, a town five miles down the road from Kitty Hawk, North Carolina on December 17, 1903

The first flight by Orville Wright, of 121 feet (37 m) in 12 seconds, was recorded in a famous photograph. In the fourth flight of the same day, Wilbur Wright flew 852 feet (260 m) in 59 seconds. The flights were witnessed by 4 lifesavers and a boy from the village, making them the first public flights and certainly the first well-documented ones.

The telegram station the Wright Brothers used to send their message of successful, sustained, powered flight is now a restaurant named "The Black Pelican."

[edit] Other early flights

At the time, a number of other inventors had made (or claimed to have made) short flights. Gustave Whitehead reported that he had flown a powered aircraft on 14 August, 1901. He failed to document the flight, but a later replica of his Number 21 was flown successfully. Lyman Gilmore also claimed to have achieved success on 15 May, 1902. In New Zealand, South Canterbury farmer and inventor Richard Pearse constructed a monoplane aircraft that he reputedly flew on March 31 1903. However, even Pearse himself admitted the flight was uncontrolled and ended in a crash-landing on a hedge without having gained any altitude.

Karl Jatho conducted a short motorized flight in August 1903, just a few months after Pearse. Jatho's wing design and airspeed did not allow his control surfaces to act properly to control the aircraft.

Also in the summer of 1903, eyewitnesses claimed to have seen Preston Watson make his initial flights at Errol, near Dundee in the east of Scotland. Once again, however, lack of photographic or documentary evidence makes the claim difficult to verify. Many claims of flight are complicated by the fact that many early flights were done at such low altitude that they did not clear the ground effect, and by the complexities involved in the differences between unpowered and powered aircraft.

The Wright Brothers conducted numerous additional public flights (over 80) in 1904 and 1905 from Huffman Prairie in Dayton, Ohio and invited friends, neighbors and newspaper reporters to them although few came.

Alberto Santos-Dumont made a public flight in Europe on September 13, 1906 in Paris. He used a canard elevator and wing-warping, and covered a distance of 221 m (725 ft). Since the plane did not need headwinds or catapults to take off, this flight is considered by some as the first true powered flight. Also, since the earlier attempts of Pearse, Jatho, Watson, and the Wright brothers received less attention from the popular press than Santos-Dumont's flight, its importance to society, especially in Europe and Brazil, is often considered to be greater despite occurring some years later.

Two English inventors Henry Farman and John William Dunne were also working separately on powered flying machines. In January 1908, Farman won the Grand Prix d'Aviation with a machine which flew for 1 km, though by this time many longer flights had already been done. For example, the Wright Brothers had made flights over 39 km long by 1905. Dunne's early work was sponsored by the British military, and tested in great secrecy in Glen Tilt in the Scottish Highlands. His best early design, the D4, flew in December 1908 near Blair Atholl in Perthshire. Dunne's main contribution to early aviation was stability, which was a key problem with the planes designed by the Wright brothers and Samuel Cody.

On May 14, 1908 the Wright Brothers made what is accepted to be the first two-person aircraft flight, with Charlie Furnas as a passenger.

On 8 July 1908, Thérèse Peltier became the first woman to fly as a passenger in an airplane when she made a flight of 656 feet with Léon Delagrance in Milan, Italy.

Thomas Selfridge became the first person killed in a powered aircraft on September 17, 1908, when Orville crashed his two-passenger plane during military tests at Fort Myer in Virginia.

In late 1908, Mrs Hart O. Berg became the first American woman to fly as a passenger in an airplane when she flew with Wilbur Wright in Le Mans, France.

On 25 July 1909 Frenchman Louis Blériot became the first person to cross the English Channel in an aircraft. His flight from Calais to Dover lasted 37 minutes. The flight followed the development of his Blériot XI monoplane which he used in the crossing. Upon successfully crossing the Channel Blériot received a prize of £1000 from the London Daily Mail.

Controversy over who gets credit for invention of the aircraft has been fuelled by Pearse's and Jatho's essentially non-existent efforts to inform the popular press, by the Wrights' secrecy while their patent was prepared, by the pride of nations, and by the number of firsts made possible by the basic invention. For example, the Romanian engineer Traian Vuia (1872 - 1950) has also been claimed to have built the first self-propelled, heavier-than-air aircraft able to take off autonomously, without a headwind and entirely driven by its own power. Vuia piloted the aircraft he designed and built on March 18, 1906, at Montesson, near Paris. None of his flights were longer than 100 feet (30 m) in length. In comparison, in October 1905, the Wright brothers had a sustained flight of 39 minutes and 24.5 miles (39 km), circling over Huffman Prairie.

The first helicopter known to have risen off the ground took place in 1907 (Cornu, France) though the first practical helicopter was the Focke FA-61 (Germany, 1936).

[edit] 1914 - 1918: World War I

Main article: World War I Aviation

Almost as soon as they were invented, planes were drafted for military service. The first country to use planes for military purposes was Bulgaria, whose planes attacked and reconnoitred the Ottoman positions during the First Balkan War 1912-13. The first war to see major use of planes in offensive, defensive and reconnaissance capabilities was World War I. The Allies and Central Powers both used planes extensively. The most famous plane of the war is the Sopwith Camel; it was credited with more aerial victories than any other Allied plane, but was also notorious for its awkward handling resulting in the death of many pilots.

Aviators were styled as modern day knights, doing individual combat with their enemies. Several pilots became famous for their air to air combats, the most well-known is Manfred von Richthofen, better known as the Red Baron, who shot down 80 planes in air to air combat with several different planes, the most celebrated of which was the Fokker Dr.I. On the allied side, René Paul Fonck is credited with the most victories.

While the concept of using the aeroplane as a weapon of war was generally laughed at before World War I, the idea of using it for photography was one that was not lost on any of the major forces. All of the major forces in Europe had light aircraft, typically derived from pre-war sporting designs, attached to their reconnaissance departments. While early efforts were hampered by the light loads carried, improved two-seat designs soon appeared that were entirely practical.

It was not long before aircraft were shooting at each other, but the lack of any sort of steady point for the gun was a problem. The French solved this problem when, in late 1914, Roland Garros attached a fixed machine gun to the front of his plane, but it was Adolphe Pegoud who would become known as the first "ace", getting credit for five victories, before also becoming the first ace to die in action.

[edit] 1918 - 1939 (The "Golden Age")

The years between World War I and World War II saw a large advancement in aircraft technology.

Aircraft evolved from being constructed of mostly wood and canvas to being constructed almost entirely of aluminium. Engine development proceeded apace, with engines moving from in-line water cooled gasoline engines to rotary air cooled engines, with a commensurate increase in propulsive power. Pushing all of this forward were prizes for distance and speed records. For example Charles Lindbergh took the Orteig Prize of $25,000 for his solo non-stop crossing of the Atlantic, the first person to achieve this, although not the first to carry out a non-stop crossing. That was achieved eight years earlier when Captain John Alcock and Lieutenant Arthur Brown co-piloted a Vickers Vimy nonstop from St. John's, Newfoundland to Clifden, Ireland on June 14, 1919, winning the £10,000 ($50,000) Northcliffe prize.

After WWI experienced fighter pilots were eager to show off their new skills. Many American pilots became barnstormers, flying into small towns across the country and showing off their flying abilities, as well as taking paying passengers for rides. Eventually the barnstormers grouped into more organized displays. Air shows sprang up around the country, with air races, acrobatic stunts, and feats of air superiority. The air races drove engine and airframe development - the Schneider Trophy for example led to a series of ever faster and sleeker monoplane designs culminating in the Supermarine S.6B, a direct forerunner of the Spitfire. With pilots competing for cash prizes, there was an incentive to go faster. Amelia Earhart was perhaps the most famous of those on the barnstorming/air show circuit. She was also the first female pilot to achieve records such as crossing of the Atlantic and English channels.

The first lighter-than-air crossings of the Atlantic were made by airship in July 1919 by His Majesty's Airship R34 and crew when they flew from East Lothian, Scotland to Long Island, New York and then back to Pulham, England. By 1929, airship technology had advanced to the point that the first round-the-world flight was completed by the Graf Zeppelin in September and in October, the same aircraft inaugurated the first commercial transatlantic service. However the age of the dirigible ended in 1937 with the terrible fire aboard the Zeppelin Hindenburg. After the now famous footage of the Hindenburg burning and crashing on the Lakehurst, New Jersey, landing field, people stopped using airships, despite the fact that most people on board survived. The Hindenburg, combined with the Winged Foot Express disaster that occurred on 21 July, 1919, in Chicago, Illinois, in which 12 civilians died, started the demise of the airship. Flammable gas dirigibles did not burn and crash often, but when they did crash they caused a disproportionate amount of destruction to the crash zone compared with the aeroplanes of the time. It was more shock value than the number of fatalities that caused the retirement of the world's airships. This may not have been the case had helium been available to the Zeppelin company. The United States, holder of the world's only reserves of helium at the time, was loathe to supply it to the company, which was based in Nazi Germany.

In the 1930s development of the jet engine began in Germany and in England. In England Frank Whittle patented a design for a jet engine in 1930 and began developing an engine towards the end of the decade. In Germany Hans von Ohain patented his version of a jet engine in 1936 and began developing a similar engine. The two men were unaware of each others work, and both Germany and Britain had developed jet aircraft by the end of World War II.

[edit] 1939-1945: World War II

World War II saw a drastic increase in the pace of aircraft development and production. All countries involved in the war stepped up production and development of aircraft and flight based weapon delivery systems, such as the German V-2 missile, and World War two saw the development of the first long range bomber, and the first jet fighter. The first functional jetplane which was the Heinkel He 178 (Germany), flown by Erich Warsitz in 1939. An earlier prototype was the Coanda-1910 that did a short flight in December 16, 1910. The first cruise missile (V-1), and the first ballistic missile (V-2) were also developed by Germany. Jet fighters did not have significant impact, nor cruise and ballistic missiles in part because the V-1 was not very effective and the V-2 was never produced in useful numbers. The P-51 Mustang was critical to the success of the heavy bomber, allowing much lower losses than otherwise. The following table shows aircraft production in the United States, and how it drastically increased over the course of the war.

Type	1940	1941	1942	1943	1944	1945	Total
Very Heavy Bombers	0	0	4	91	1,147	2,657	3,899
Heavy Bombers	19	181	2,241	8,695	3,681	27,874	42,691
Medium Bombers	24	326	2,429	3,989	3,636	1,432	11,836
Light Bombers	16	373	1,153	2,247	2,276	1,720	7,785
Fighters	187	1,727	5,213	11,766	18,291	10,591	47,775
Reconnaissance	10	165	195	320	241	285	1,216
Transports	5	133	1,264	5,072	6,430	3,043	15,947
Trainers	948	5,585	11,004	11,246	4,861	825	34,469
Communication/ Liaison	0	233	2,945	2,463	1,608	2,020	9,269
Total by Year	1,209	8,723	26,448	45,889	51,547	26,254	160,070

See Also: List of aircraft of World War II

[edit] 1945 - 1991: The Cold War

Commercial Aviation took hold after World War II using mostly ex-military aircraft in the business of transporting people and goods. Within a few years many companies existed, with routes that criss-crossed North America, Europe and other parts of the world. This was accelerated due to the glut of heavy and super-heavy bomber airframes like the B-29 and Lancaster that could easily be converted into commercial aircraft. The DC-3 also made for easier and longer commercial flights. By 1952, the British state airline BOAC introduced into service the first jet airliner, the De Havilland Comet. While a technical achievement, the plane suffered a series of highly public failures, as the shape of the windows led to cracks due to metal fatigue. The fatigue was caused by cycles of pressurization and depressurization of the cabin, and eventually led to catastrophic failure of the plane's fuselage. By the time the problems were overcome, other jet airliner designs had already taken to the skies, including the Boeing 707, which established new levels of comfort, safety and passenger expectations. The 707 ushered in the age of mass commercial air travel as we enjoy it today.

Even with the end of World War II, there was still a need for advancement in aircraft and rocket technology. Not long after the war ended, in October of 1947, Chuck Yeager took the rocket powered Bell X-1 past the speed of sound. Although anecdotal evidence exists that some fighter pilots may have done so while divebombing ground targets during the war, this is the first controlled, level flight to cross the sound barrier. Further barriers of distance were eliminated in 1948 and 1952 as the first jet crossing of the Atlantic occurred and the first nonstop flight to Australia occurred.

During the 1950's, a new age of military aviation history would be written. When the Soviet Union developed long-range bombers that could deliver nuclear weapons to North America and Europe, Western countries responded with interceptor aircraft that could engage and destroy the bombers before they reached their destination. The Canadian government under the leadership of William Lyon Mackenzie King built the Avro Arrow, the fastest aircraft in its time. However, by 1955, most Western countries agreed that the interceptor age was replaced by guided missile age. Consequently, the Avro Arrow project was eventually cancelled under Prime Minister John Diefenbaker. See Avro Arrow for more details.

In 1961, the sky was no longer the limit for manned flight, as Yuri Gagarin orbited once around the planet within 108 minutes. This action further heated up the space race that had started in 1957 with the launch of Sputnik 1 by the Soviet Union. The United States responded by launching Alan Shepard into space on a suborbital flight in a Mercury space capsule. With the launch of the Alouette I in 1963, Canada became the third country to send a satellite in space. The Space race between the United States and the Soviet Union would ultimately lead to the current pinnacle of human flight, the landing of men on the moon in 1969.

This historic achievement in space was not the only progress made in aviation at this time however. In 1967, the X-15 set the air speed record for an aircraft at 4,534 mph or Mach 6.1 (7,297 km/h). Aside from vehicles designed to fly in outer space, this record still stands as the air speed record for powered flight.

The same year that Neil Armstrong and Buzz Aldrin set foot on the moon, 1969, Boeing came out with its vision for the future of air travel, unveiling the Boeing 747 for the first time. This plane is still one of the largest aircraft ever to fly, and it carries millions of passengers each year. Commercial aviation progressed even further in 1976 as British Airways inagurated supersonic service across the Atlantic, courtesy of the Concorde. A few years earlier the SR-71 Blackbird had set the record for crossing the Atlantic in under 2 hours, and Concorde followed in its footsteps with passengers in tow.

The last quarter of the 20th century saw a slowing of the pace of advancement seen in the first three quarters of the century. No longer was revolutionary progress made in flight speeds, distances and technology. This part of the century saw the steady improvement of flight avionics, and a few minor milestones in flight progress.

For example, in 1979 the Gossamer Albatross became the first human powered aircraft to cross the English channel. This achievement finally saw the realization of centuries of dreams of human flight, but this has not had any significant impact on either commercial or military aviation. In 1986 Dick Rutan and Jeana Yeager flew an aircraft around the world unrefuelled, and without landing. In 1999 Bertrand Piccard became the first person to circle the earth in a balloon. By the end of the 20th Century there were no major or minor accomplishments left to be made in subsonic aviation. Focus was turning to the ultimate conquest of space and flight at faster than the speed of sound. The ANSARI X PRIZE inspired entrepreneurs and space enthusiasts to build their own rocket ships to fly faster than sound and climb into the lowest reaches of space.

[edit] 2001-Future

In the beginning of the 21st century, subsonic aviation focused on eliminating the pilot in favor of remotely operated or completely autonomous vehicles. Several Unmanned aerial vehicles or UAVs have been developed. In April 2001 the unmanned aircraft Global Hawk flew from Edwards AFB in the US to Australia non-stop and unrefuelled. This is the longest point-to-point flight ever undertaken by an unmanned aircraft, and took 23 hours and 23 minutes. In October 2003 the first totally autonomous flight across the Atlantic by a computer-controlled model aircraft occurred.

In commercial aviation, the early 21st century saw the end of an era with the retirement of Concorde. Supersonic flight was not very commercially viable, as the planes were required to fly over the oceans if they wanted to break the sound barrier. Concorde also was fuel hungry and could carry a limited amount of passengers due to its highly streamlined design. Nevertherless, it seems to have made a significant operating profit for British Airways.

Despite this setback, and the general slowing of progress, it is generally agreed that the 21st century will be a bright one for aviation. Planes and rockets offer unique capabilities in terms of speed and carrying capacity that should not be underestimated. As long as there is a need for people to get to places quickly, there will be a need for aviation.

The obvious limits are Future energy development and Global warming. It does not appear to be possible to decrease the fuel consumption of aircraft as much as that of cars or of space heating.

[edit] See also

• Timeline of aviation
• Early flight
• Early flying machines
• First flying machine
• List of aircraft
• Accidents and incidents in aviation
• Aviation archaeology
• Model aircraft

[edit] External links

• http://www.flyingmachines.org/
• http://www.thewrightbrothers.org/fivefirstflights.html
• Time line of greatest breakthroughs in manned flight
• Prehistory of Flight
• Graphic time-line
• little aviation games
• Private Jet Charter History
• University of Washington Libraries Digital Collections – Transportation Photographs An ongoing digital collection of photographs depicting various modes of transportation in the Pacific Northwest region and Western United States during the first half of the 20th century.
• World Aviation Disasters Timeline of the 21st Century