The term aviation, noun of action from stem of Latin avis “bird” with suffix -ation meaning action or progress, was coined in 1863 by French pioneer Guillaume Joseph Gabriel de La Landelle (1812–1886) in “Aviation ou Navigation aérienne sans ballons”.
The Wright brothers
Using a methodological approach and concentrating on the controllability of the aircraft, 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. 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 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 head wind. 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 December 17, 1903.
The first flight by Orville Wright, of 120 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 three coastal lifesaving crewmen, a local businessman, and a boy from the village, making these the first public flights and the first well-documented ones.
Orville described the final flight of the day: “The first few hundred feet were up and down, as before, but by the time three hundred feet had been covered, the machine was under much better control. The course for the next four or five hundred feet had but little undulation. However, when out about eight hundred feet the machine began pitching again, and, in one of its darts downward, struck the ground. The distance over the ground was measured to be 852 feet (260 m); the time of the flight was 59 seconds. The frame supporting the front rudder was badly broken, but the main part of the machine was not injured at all. We estimated that the machine could be put in condition for flight again in about a day or two.” They flew only about ten feet above the ground as a safety precaution, so they had little room to maneuver, and all four flights in the gusty winds ended in a bumpy and unintended “landing”. Modern analysis by Professor Fred E. C. Culick and Henry R. Rex (1985) has demonstrated that the 1903 Wright Flyer was so unstable as to be almost unmanageable by anyone but the Wrights, who had trained themselves in the 1902 glider.
The Wrights continued flying at Huffman Prairie near Dayton, Ohio in 1904–05. In May 1904 they introduced the Flyer II, a heavier and improved version of the original Flyer. On June 23, 1905 they first flew a third machine, the Flyer III. After a severe crash on 14 July 1905, they rebuilt the Flyer III and made important design changes. They almost doubled the size of the elevator and rudder and moved them about twice the distance from the wings. They added two fixed vertical vanes (called “blinkers”) between the elevators, and gave the wings a very slight dihedral. They disconnected the rudder from the wing-warping control, and as in all future aircraft, placed it on a separate control handle. When flights resumed the results were immediate. The serious pitch instability that hampered Flyers I and II was significantly reduced, so repeated minor crashes were eliminated. Flights with the redesigned Flyer III started lasting over 10 minutes, then 20, then 30. Flyer III became the first practical aircraft (though without wheels and needing a launching device), flying consistently under full control and bringing its pilot back to the starting point safely and landing without damage. On 5 October 1905, Wilbur flew 24 miles (39 km) in 39 minutes 23 seconds.”
According to the April 1907 issue of the Scientific American magazine, the Wright brothers seemed to have the most advanced knowledge of heavier-than-air navigation at the time. However, the same magazine issue also claimed that no public flight had been made in the United States before its April 1907 issue. Hence, they devised the Scientific American Aeronautic Trophy in order to encourage the development of a heavier-than-air flying machine.
The Pioneer Era (1903–1914)
This period saw the development of practical aeroplanes and airships and their early application, alongside balloons and kites, for private, sport and military use.
European pioneers
Although full details of the Wright Brothers’ system of flight control had been published in l’Aerophile in January 1906, the importance of this advance was not recognised, and European experimenters generally concentrated on attempting to produce inherently stable machines.
Short powered flights were performed in France by Romanian engineer Traian Vuia on March 18 and August 19, 1906 when he flew 12 and 24 meters, respectively, in a self-designed, fully self-propelled, fixed-wing aircraft, that possessed a fully wheeled undercarriage. He was followed by Jacob Ellehammer who built a monoplane which he tested with a tether in Denmark on September 12, 1906, flying 42 meters.
On September 13, 1906, a day after Ellehammer’s tethered flight and three years after the Wright Brothers’ flight, Alberto Santos-Dumont made a public flight in Paris with the 14-bis, also known as Oiseau de proie (French for “bird of prey”). This was of canard configuration with pronounced wing dihedral, and covered a distance of 60 m (200 ft) on the grounds of the Chateau de Bagatelle in Paris’ Bois de Boulogne before a large crowd of witnesses. This well-documented event was the first flight verified by the Aéro-Club de France of a powered heavier-than-air machine in Europe and won the Deutsch-Archdeacon Prize for the first officially observed flight greater than 25 m (82 ft). On November 12, 1906, Santos-Dumont set the first world record recognized by the Federation Aeronautique Internationale by flying 220 m (720 ft) in 21.5 seconds. Only one more brief flight was made by the 14bis in March 1907, after which it was abandoned.
In March 1907 Gabriel Voisin flew the first example of his Voisin biplane. On 13 January 1908 a second example of the type was flown by Henri Farman to win the Deutsch-Archdeacon Grand Prix d’Aviation prize for a flight in which the aircraft flew a distance of more than a kilometer and landed at the point where it had taken off. The flight lasted 1 minute and 28 seconds.
In 1914, just before the start of World War I, Romania completed the world’s first metal-built aircraft, Vlaicu III. It was captured by the Germans in 1916 and last seen at a 1942 aviation exhibition in Berlin.
Flight as an established technology
Santos-Dumont later added ailerons, between the wings in an effort to gain more lateral stability. His final design, first flown in 1907, was the series of Demoiselle monoplanes (Nos. 19 to 22). The Demoiselle No 19 could be constructed in only 15 days and became the world’s first series production aircraft. The Demoiselle achieved 120 km/h. The fuselage consisted of three specially reinforced bamboo booms: the pilot sat a seat between the main wheels of a conventional landing gear whose pair of wire-spoked mainwheels were located at the lower front of the airframe, with a tailskid half-way back beneath the rear fuselage structure. The Demoiselle was controlled in flight by a cruciform tail unit hinged on a form of universal joint at the aft end of the fuselage structure to function as elevator and rudder, with roll control provided through wing warping (No. 20), with the wings only warping “down”.
In 1908 Wilbur Wright travelled to Europe, and starting in August gave a series of flight demonstrations at Le Mans in France. The first demonstration, made on 8 August, attracted an audience including most of the major French aviation experimenters, who were astonished by the clear superiority of the Wright Brothers’ aircraft, particularly its ability to make tight controlled turns. The importance of using roll control in making turns was recognised by almost all the European experimenters: Henri Farman fitted ailerons to his Voisin biplane and shortly afterwards set up his own aircraft construction business, whose first product was the influential Farman III biplane.
The following year saw the widespread recognition of powered flight as something other than the preserve of dreamers and eccentrics. On 25 July Louis Blériot won worldwide fame by winning a £1,000 prize offered by the British Daily Mail newspaper for a flight across the English Channel, and in August around half a million people, including the President of France Armand Fallières and David Lloyd George, attended one of the first aviation meetings, the Grande Semaine d’Aviation at Reims.
Rotorcraft
In 1877, Enrico Forlanini developed an unmanned helicopter powered by a steam engine. It rose to a height of 13 meters, where it remained for some 20 seconds, after a vertical take-off from a park in Milan.
The first time a manned helicopter is known to have risen off the ground was on a tethered flight in 1907 by the Breguet-Richet Gyroplane. Later the same year the Cornu helicopter, also French, made the first rotary-winged free flight at Lisenux, France. However, these were not practical designs.
Military use
Almost as soon as they were invented, airplanes were used for military purposes. The first country to use them for military purposes was Italy, whose aircraft made reconnaissance, bombing and artillery correction flights in Libya during the Italian-Turkish war (September 1911 – October 1912). The first mission (a reconnaissance) occurred on 23 October 1911. The first bombing mission was flown on 1 November 1911. Then Bulgaria followed this example. Its airplanes attacked and reconnoitered the Ottoman positions during the First Balkan War 1912–13. The first war to see major use of airplanes in offensive, defensive and reconnaissance capabilities was World War I. The Allies and Central Powers both used airplanes and airships extensively.
While the concept of using the airplane as an offensive weapon was generally discounted 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. Radiotelephones were also being explored on airplanes, notably the SCR-68, as communication between pilots and ground commander grew more and more important.
World War I (1914–1918)
Combat schemes
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 while Adolphe Pegoud would become known as the first “ace”, getting credit for five victories, before also becoming the first ace to die in action, it was German Luftstreitkräfte Leutnant Kurt Wintgens, who, on July 1, 1915, scored the very first aerial victory by a purpose-built fighter plane, with a synchronized machine gun.
Aviators were styled as modern-day knights, doing individual combat with their enemies. Several pilots became famous for their air-to-air combat; 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 all-time victories at 75, even when later wars are considered.
France, Britain, Germany and Italy were the leading manufacturers of fighter planes that saw action during the war, with German aviation technologist Hugo Junkers showing the way to the future through his pioneering use of all-metal aircraft from late 1915.
Between the World Wars (1918–1939)
The years between World War I and World War II saw great advancements in aircraft technology. Airplanes evolved from low-powered biplanes made from wood and fabric to sleek, high-powered monoplanes made of aluminum, based primarily on the founding work of Hugo Junkers during the World War I period and its adoption by American designer William Bushnell Stout and Soviet designer Andrei Tupolev. The age of the great rigid airships came and went. The first successful rotorcraft appeared in the form of the autogyro, invented by Spanish engineer Juan de la Cierva and first flown in 1919. In this design, the rotor is not powered but is spun like a windmill by its passage through the air. A separate powerplant is used to propel the aircraft forwards.
After World War I, experienced fighter pilots were eager to show off their 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. 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 Pacific Oceans.
Australian Sir Charles Kingsford Smith was the first to fly across the larger Pacific Ocean in the Southern Cross. His crew left Oakland, California to make the first trans-Pacific flight to Australia in three stages. The first (from Oakland to Hawaii) was 2,400 miles, took 27 hours 25 minutes and was uneventful. They then flew to Suva, Fiji 3,100 miles away, taking 34 hours 30 minutes. This was the toughest part of the journey as they flew through a massive lightning storm near the equator. They then flew on to Brisbane in 20 hours, where they landed on 9 June 1928 after approximately 7,400 miles total flight. On arrival, Kingsford Smith was met by a huge crowd of 25,000 at Eagle Farm Airport in his hometown of Brisbane. Accompanying him were Australian aviator Charles Ulm as the relief pilot, and the Americans James Warner and Captain Harry Lyon (who were the radio operator, navigator and engineer). A week after they landed, Kingsford Smith and Ulm recorded a disc for Columbia talking about their trip. With Ulm, Kingsford Smith later continued his journey being the first in 1929 to circumnavigate the world, crossing the equator twice.
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 rigid airship ended following the destruction by fire of the zeppelin LZ 129 Hindenburg just before landing at Lakehurst, New Jersey on May 6, 1937, killing 35 of the 97 people aboard. Previous spectacular airship accidents, from the Wingfoot Express disaster (1919) to the loss of the R101 (1930), the Akron (1933) and the Macon (1935) had already cast doubt on airship safety, but with the disasters of the U.S. Navy’s rigids showing the importance of solely using helium as the lifting medium; following the destruction of the Hindenburg, the remaining airship making international flights, the Graf Zeppelin was retired (June 1937). Its replacement, the rigid airship Graf Zeppelin II, made a number of flights, primarily over Germany, from 1938 to 1939, but was grounded when Germany began World War II. Both remaining German zeppelins were scrapped in 1940 to supply metal for the German Luftwaffe; the last American rigid airship, the Los Angeles, which had not flown since 1932, was dismantled in late 1939.
Meanwhile, Germany, which was restricted by the Treaty of Versailles in its development of powered aircraft, developed gliding as a sport, especially at the Wasserkuppe, during the 1920s. In its various forms, in the 21st century sailplane aviation now has over 400,000 participants.
In 1929 Jimmy Doolittle developed instrument flight.
1929 also saw the first flight of by far the largest plane ever built until then: the Dornier Do X with a wing span of 48 m. On its 70th test flight on October 21 there were 169 people on board, a record that was not broken for 20 years.
Less than a decade after the development of the first practical rotorcraft of any type with the autogyro, in the Soviet Union, Boris N. Yuriev and Alexei M. Cheremukhin, two aeronautical engineers working at the Tsentralniy Aerogidrodinamicheskiy Institut, constructed and flew the TsAGI 1-EA single rotor helicopter, which used an open tubing framework, a four blade main rotor, and twin sets of 1.8-meter (5.9 ft) diameter anti-torque rotors; one set of two at the nose and one set of two at the tail. Powered by two M-2 powerplants, up-rated copies of the Gnome Monosoupape rotary radial engine of World War I, the TsAGI 1-EA made several successful low altitude flights. By 14 August 1932, Cheremukhin managed to get the 1-EA up to an unofficial altitude of 605 meters (1,985 feet) with what is likely to be the first successful single-lift rotor helicopter design ever tested and flown.
Only five years after the German Dornier Do-X had flown, Tupolev designed the largest aircraft of the 1930s era, the Maksim Gorky in the Soviet Union by 1934, as the largest aircraft ever built using the Junkers methods of metal aircraft construction.
In the 1930s development of the jet engine began in Germany and in Britain – both countries would go on to develop jet aircraft by the end of World War II.
World War II (1939–1945)
World War II saw a great increase in the pace of development and production, not only of aircraft but also the associated flight-based weapon delivery systems. Air combat tactics and doctrines took advantage. Large-scale strategic bombing campaigns were launched, fighter escorts introduced and the more flexible aircraft and weapons allowed precise attacks on small targets with dive bombers, fighter-bombers, and ground-attack aircraft. New technologies like radar also allowed more coordinated and controlled deployment of air defense.
The first jet aircraft to fly was the Heinkel He 178 (Germany), flown by Erich Warsitz in 1939, followed by the world’s first operational jet aircraft, the Me 262, in July 1942 and world’s first jet-powered bomber, the Arado Ar 234, in June 1943. British developments, like the Gloster Meteor, followed afterwards, but saw only brief use in World War II. The first cruise missile (V-1), the first ballistic missile (V-2), the first (and to date only) operational rocket-powered combat aircraft Me 163—with attained velocities of up to 1,130 km/h (700 mph) in test flights—and the first vertical take-off manned point-defense interceptor, the Bachem Ba 349 Natter, were also developed by Germany. However, jet and rocket aircraft had only limited impact due to their late introduction, fuel shortages, the lack of experienced pilots and the declining war industry of Germany.
Not only airplanes, but also helicopters saw rapid development in the Second World War, with the introduction of the Focke Achgelis Fa 223, the Flettner Fl 282 synchropter in 1941 in Germany and the Sikorsky R-4 in 1942 in the USA.
The postwar era (1945–1979)
After World War II, commercial aviation grew rapidly, using mostly ex-military aircraft to transport people and cargo. This growth was accelerated by the glut of heavy and super-heavy bomber airframes like the B-29 and Lancaster that could be converted into commercial aircraft. The DC-3 also made for easier and longer commercial flights. The first commercial jet airliner to fly was the British de Havilland Comet. By 1952, the British state airline BOAC had introduced the Comet into scheduled service. 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.
USSR’s Aeroflot became the first airline in the world to operate sustained regular jet services on September 15, 1956 with the Tupolev Tu-104. The Boeing 707 and DC-8 which established new levels of comfort, safety and passenger expectations, ushered in the age of mass commercial air travel, dubbed the Jet Age.
In October 1947 Chuck Yeager took the rocket-powered Bell X-1 through the sound barrier. Although anecdotal evidence exists that some fighter pilots may have done so while dive bombing ground targets during the war, this was the first controlled, level flight to exceed the speed of sound. Further barriers of distance fell in 1948 and 1952 with the first jet crossing of the Atlantic and the first nonstop flight to Australia.
The 1945 invention of nuclear bombs briefly increased the strategic importance of military aircraft in the Cold War between East and West. Even a moderate fleet of long-range bombers could deliver a deadly blow to the enemy, so great efforts were made to develop countermeasures. At first, the supersonic interceptor aircraft were produced in considerable numbers. By 1955 most development efforts shifted to guided surface-to-air missiles. However, the approach diametrically changed when a new type of nuclear-carrying platform appeared that could not be stopped in any feasible way: intercontinental ballistic missiles. The possibility of these was demonstrated in 1957 with the launch of Sputnik 1 by the Soviet Union. This action started the Space Race between the nations.
In 1961, the sky was no longer the limit for manned flight, as Yuri Gagarin orbited once around the planet within 108 minutes, and then used the descent module of Vostok I to safely reenter the atmosphere and reduce speed from Mach 25 using friction and converting the kinetic energy of the velocity into heat. 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 into space. The space race between the United States and the Soviet Union would ultimately lead to the landing of men on the moon in 1969.
In 1967, the X-15 set the air speed record for an aircraft at 4,534 mph (7,297 km/h) or Mach 6.1. Aside from vehicles designed to fly in outer space, this record was renewed by X-43 in the 21st century.
The Harrier Jump Jet, often referred to as just “Harrier” or “the Jump Jet”, is a British designed military jet aircraft capable of Vertical/Short Takeoff and Landing (V/STOL) via thrust vectoring. It first flew in 1969, the same year that Neil Armstrong and Buzz Aldrin set foot on the moon, and Boeing unveiled the Boeing 747 and the Aérospatiale-BAC Concorde supersonic passenger airliner had its maiden flight. The Boeing 747 was the largest commercial passenger aircraft ever to fly, and still carries millions of passengers each year, though it has been superseded by the Airbus A380, which is capable of carrying up to 853 passengers. In 1975 Aeroflot started regular service on the Tu-144—the first supersonic passenger plane. In 1976 British Airways and Air France began supersonic service across the Atlantic, with 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.
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.
The digital age (1980–present)
The last quarter of the 20th century saw a change of emphasis. No longer was revolutionary progress made in flight speeds, distances and materials technology. This part of the century instead saw the spreading of the digital revolution both in flight avionics and in aircraft design and manufacturing techniques.
In 1986 Dick Rutan and Jeana Yeager flew an aircraft, the Rutan Voyager, around the world unrefuelled, and without landing. In 1999 Bertrand Piccard became the first person to circle the earth in a balloon.
Digital fly-by-wire systems allow an aircraft to be designed with relaxed static stability. Initially used to increase the manoeuvrability of military aircraft such as the General Dynamics F-16 Fighting Falcon, this is now being used to reduce drag on commercial airliners.
The U.S. Centennial of Flight Commission was established in 1999 to encourage the broadest national and international participation in the celebration of 100 years of powered flight. It publicized and encouraged a number of programs, projects and events intended to educate people about the history of aviation.
21st century
21st century aviation has seen increasing interest in fuel savings and fuel diversification, as well as low cost airlines and facilities. Additionally, much of the developing world that did not have good access to air transport has been steadily adding aircraft and facilities, though severe congestion remains a problem in many up and coming nations. Some 20,000 city pairs are served by commercial aviation, up from less than 10,000 as recently as 1996.
There appears to be newfound interest in returning to the supersonic era whereby waning demand and bureaucratic hurdles in the turn of the 20th century made flights unprofitable, as well as the final commercial stoppage of the Concorde due to a fatal accident.
In the beginning of the 21st century, digital technology allowed subsonic military aviation to begin eliminating the pilot in favor of remotely operated or completely autonomous unmanned aerial vehicles (UAVs). 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. UAVs are now an established feature of modern warfare, carrying out pinpoint attacks under the control of a remote operator.
Major disruptions to air travel in the 21st century included the closing of U.S. airspace due to the September 11 attacks, and the closing of most of European airspace after the 2010 eruption of Eyjafjallajökull.
In 2015, André Borschberg flew a record distance of 4481 miles (7212 km) from Nagoya, Japan to Honolulu, Hawaii in a solar-powered plane, Solar Impulse 2. The flight took nearly five days; during the nights the aircraft used its batteries and the potential energy gained during the day.
The future
Since the beginning of the 1990s, commercial aviation has gone on to develop technologies that in the future will make the aircraft an increasingly automated device, gradually reducing the importance of the pilot in the operations of the aircraft, with the intention of reducing Air accidents caused by human failures. Commercial aircraft manufacturers continue to investigate possible ways to improve them, making them increasingly safe, efficient and silent devices. At the same time, the pilots, air and mechanical controllers will be better prepared and the aircraft will pass more rigorous revisions in order to avoid accidents due to human or mechanical failures.
The reusable launch system, also known by its acronym in English RLV ( Reusable Launch Vehicle ) is a launch vehicle that is capable of being launched into space more than once, thanks to its reusable rockets, which would generate enough thrust to reach the space and once there, orbit around the planet. These aircraft can take off and land in the same way as aircraft, on long runways. Although not yet available, there are several models that are in the testing phase, such as SpaceShipOne, which became the first manned space vehicle of private capital. Over time they could be used for the realization of space travel, low cost and high security. However, so that they can be used on multiple occasions, it is necessary that they have a more resistant structure to withstand continued use, which would increase the weight of the device, and given the lack of experience with these vehicles, the costs have yet to be considered. that would imply its realization.
New cleaner energy sources are also being investigated, such as ethanol, electricity, or even using photovoltaic solar energy. With the latter, NASA created the Helios, a plane powered by the energy provided by the sun and its photovoltaic cells installed on its entire wing surface. The Helios broke the record of height in this type of apparatus, And it is also capable of staying for days in flight, which means that in the future, similar aircraft can be used as cheaper satellites. Other private initiatives, such as the Solar Impulse airplane, have been developing in recent years, predicting the forthcoming takeoff of solar aviation.
Despite the growing problems that aviation has faced in general, it is believed that the 21st century will be a century of advances within the aviation world. Airplanes and rockets will offer unique capabilities in terms of speed and capacity of passengers and cargo that should not be underestimated. As long as people have transportation needs from one point of the planet to another at high speed, aviation will always be necessary.
Source from Wikipedia