Aeronautics

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Space Shuttle Atlantis on a Shuttle Carrier Aircraft. Atlantis on Shuttle Carrier Aircraft.jpg
Space Shuttle Atlantis on a Shuttle Carrier Aircraft.

Aeronautics is the science or art involved with the study, design, and manufacturing of air flight capable machines, and the techniques of operating aircraft and rockets within the atmosphere. The British Royal Aeronautical Society identifies the aspects of "aeronautical Art, Science and Engineering" and "the profession of Aeronautics (which expression includes Astronautics)." [1]

Flight Process by which an object moves, through an atmosphere or beyond it

Flight is the process by which an object moves through an atmosphere without contact with the surface. This can be achieved by generating aerodynamic lift associated with propulsive thrust, aerostatically using buoyancy, or by ballistic movement.

Aircraft machine that is able to fly by gaining support from the air other than the reactions of the air against the earth’s surface

An aircraft is a machine that is able to fly by gaining support from the air. It counters the force of gravity by using either static lift or by using the dynamic lift of an airfoil, or in a few cases the downward thrust from jet engines. Common examples of aircraft include airplanes, helicopters, airships, gliders, paramotors and hot air balloons.

Atmosphere The layer of gases surrounding an astronomical body held by gravity

An atmosphere is a layer or a set of layers of gases surrounding a planet or other material body, that is held in place by the gravity of that body. An atmosphere is more likely to be retained if the gravity it is subject to is high and the temperature of the atmosphere is low.

Contents

While the term originally referred solely to operating the aircraft, it has since been expanded to include technology, business, and other aspects related to aircraft. [2] The term "aviation" is sometimes used interchangeably with aeronautics, although "aeronautics" includes lighter-than-air craft such as airships, and includes ballistic vehicles while "aviation" technically does not. [2]

Aviation Design, development, production, operation and use of aircraft

Aviation, or air transport, refers to the activities surrounding mechanical flight and the aircraft industry. Aircraft includes fixed-wing and rotary-wing types, morphable wings, wing-less lifting bodies, as well as lighter-than-air craft such as balloons and airships.

Airship type of aerostat or lighter-than-air aircraft

An airship or dirigible balloon is a type of aerostat or lighter-than-air aircraft that can navigate through the air under its own power. Aerostats gain their lift from large gasbags filled with a lifting gas that is less dense than the surrounding air.

A significant part of aeronautical science is a branch of dynamics called aerodynamics, which deals with the motion of air and the way that it interacts with objects in motion, such as an aircraft.

Dynamics is the branch of classical mechanics concerned with the study of forces and their effects on motion. Isaac Newton defined the fundamental physical laws which govern dynamics in physics, especially his second law of motion.

Aerodynamics branch of dynamics concerned with studying the motion of air

Aerodynamics, from Greek ἀήρ aer (air) + δυναμική (dynamics), is the study of motion of air, particularly as interaction with a solid object, such as an airplane wing. It is a sub-field of fluid dynamics and gas dynamics, and many aspects of aerodynamics theory are common to these fields. The term aerodynamics is often used synonymously with gas dynamics, the difference being that "gas dynamics" applies to the study of the motion of all gases, and is not limited to air. The formal study of aerodynamics began in the modern sense in the eighteenth century, although observations of fundamental concepts such as aerodynamic drag were recorded much earlier. Most of the early efforts in aerodynamics were directed toward achieving heavier-than-air flight, which was first demonstrated by Otto Lilienthal in 1891. Since then, the use of aerodynamics through mathematical analysis, empirical approximations, wind tunnel experimentation, and computer simulations has formed a rational basis for the development of heavier-than-air flight and a number of other technologies. Recent work in aerodynamics has focused on issues related to compressible flow, turbulence, and boundary layers and has become increasingly computational in nature.

History

Early ideas

Designs for flying machines by Leonardo da Vinci, circa 1490 Leonardo da Vinci helicopter and lifting wing.jpg
Designs for flying machines by Leonardo da Vinci, circa 1490

Attempts to fly without any real aeronautical understanding have been made from the earliest times, typically by constructing wings and jumping from a tower with crippling or lethal results. [3]

Wiser investigators sought to gain some rational understanding through the study of bird flight. An early example appears in ancient Egyptian texts.[ citation needed ] Later medieval Islamic scientists also made such studies. The founders of modern aeronautics, Leonardo da Vinci in the Renaissance and Cayley in 1799, both began their investigations with studies of bird flight.

Leonardo da Vinci 15th and 16th-century Italian Renaissance polymath

Leonardo di ser Piero da Vinci, more commonly Leonardo da Vinci or simply Leonardo, was an Italian polymath of the Renaissance whose areas of interest included invention, drawing, painting, sculpting, architecture, science, music, mathematics, engineering, literature, anatomy, geology, astronomy, botany, writing, history, and cartography. He has been variously called the father of palaeontology, ichnology, and architecture, and he is widely considered one of the greatest painters of all time. Leonardo is renowned primarily as a painter. The Mona Lisa is the most famous of his works and the most parodied portrait, and The Last Supper is the most reproduced religious painting of all time. His drawing of the Vitruvian Man is also regarded as a cultural icon, being reproduced on items as varied as the euro coin, textbooks, and T-shirts. Perhaps 15 of his paintings have survived. Nevertheless, these few works compose a contribution to later generations of artists rivalled only by that of his contemporary Michelangelo, together with his notebooks, which contain drawings, scientific diagrams, and his thoughts on the nature of painting.

Man-carrying kites are believed to have been used extensively in ancient China. In 1282 the European explorer Marco Polo described the Chinese techniques then current. [4] The Chinese also constructed small hot air balloons, or lanterns, and rotary-wing toys.

Marco Polo Venetian explorer and merchant noted for travel to central and eastern Asia

Marco Polo was an Italian merchant, explorer, and writer, born in the Republic of Venice. His travels are recorded in Livre des merveilles du monde, a book that described to Europeans the wealth and great size of China, its capital Peking, and other Asian cities and countries.

An early European to provide any scientific discussion of flight was Roger Bacon, who described principles of operation for the lighter-than-air balloon and the flapping-wing ornithopter, which he envisaged would be constructed in the future. The lifting medium for his balloon would be an "aether" whose composition he did not know. [5]

In the late fifteenth century, Leonardo da Vinci followed up his study of birds with designs for some of the earliest flying machines, including the flapping-wing ornithopter and the rotating-wing helicopter. Although his designs were rational, they were not based on particularly good science. [6] Many of his designs, such as a four-person screw-type helicopter, have severe flaws. He did at least understand that "An object offers as much resistance to the air as the air does to the object." [7] (Newton would not publish the Third law of motion until 1687.) His analysis led to the realisation that manpower alone was not sufficient for sustained flight, and his later designs included a mechanical power source such as a spring. Da Vinci's work was lost after his death and did not reappear until it had been overtaken by the work of George Cayley.

Balloon flight

Francesco Lana de Terzi's flying boat concept c.1670 Flying boat.png
Francesco Lana de Terzi's flying boat concept c.1670

The modern era of lighter-than-air flight began early in the 17th century with Galileo's experiments in which he showed that air has weight. Around 1650 Cyrano de Bergerac wrote some fantasy novels in which he described the principle of ascent using a substance (dew) he supposed to be lighter than air, and descending by releasing a controlled amount of the substance. [8] Francesco Lana de Terzi measured the pressure of air at sea level and in 1670 proposed the first scientifically credible lifting medium in the form of hollow metal spheres from which all the air had been pumped out. These would be lighter than the displaced air and able to lift an airship. His proposed methods of controlling height are still in use today; by carrying ballast which may be dropped overboard to gain height, and by venting the lifting containers to lose height. [9] In practice de Terzi's spheres would have collapsed under air pressure, and further developments had to wait for more practicable lifting gases.

Montgolfier brothers flight, 1784 Montgolfier brothers flight.jpg
Montgolfier brothers flight, 1784

From the mid-18th century the Montgolfier brothers in France began experimenting with balloons. Their balloons were made of paper, and early experiments using steam as the lifting gas were short-lived due to its effect on the paper as it condensed. Mistaking smoke for a kind of steam, they began filling their balloons with hot smoky air which they called "electric smoke" and, despite not fully understanding the principles at work, made some successful launches and in 1783 were invited to give a demonstration to the French Académie des Sciences.

Meanwhile, the discovery of hydrogen led Joseph Black in c. 1780 to propose its use as a lifting gas, though practical demonstration awaited a gas tight balloon material. On hearing of the Montgolfier Brothers' invitation, the French Academy member Jacques Charles offered a similar demonstration of a hydrogen balloon. Charles and two craftsmen, the Robert brothers, developed a gas tight material of rubberised silk for the envelope. The hydrogen gas was to be generated by chemical reaction during the filling process.

The Montgolfier designs had several shortcomings, not least the need for dry weather and a tendency for sparks from the fire to set light to the paper balloon. The manned design had a gallery around the base of the balloon rather than the hanging basket of the first, unmanned design, which brought the paper closer to the fire. On their free flight, De Rozier and d'Arlandes took buckets of water and sponges to douse these fires as they arose. On the other hand, the manned design of Charles was essentially modern. [10] As a result of these exploits, the hot-air balloon became known as the Montgolfière type and the hydrogen balloon the Charlière.

Charles and the Robert brothers' next balloon, La Caroline , was a Charlière that followed Jean Baptiste Meusnier's proposals for an elongated dirigible balloon, and was notable for having an outer envelope with the gas contained in a second, inner ballonet. On 19 September 1784, it completed the first flight of over 100 km, between Paris and Beuvry, despite the man-powered propulsive devices proving useless.

In an attempt the next year to provide both endurance and controllability, de Rozier developed a balloon having both hot air and hydrogen gas bags, a design which was soon named after him as the Rozière. The principle was to use the hydrogen section for constant lift and to navigate vertically by heating and allowing to cool the hot air section, in order to catch the most favourable wind at whatever altitude it was blowing. The balloon envelope was made of goldbeater's skin. The first flight ended in disaster and the approach has seldom been used since. [11]

Cayley and the foundation of modern aeronautics

Sir George Cayley (1773-1857) is widely acknowledged as the founder of modern aeronautics. He was first called the "father of the aeroplane" in 1846 [12] and Henson called him the "father of aerial navigation." [3] He was the first true scientific aerial investigator to publish his work, which included for the first time the underlying principles and forces of flight. [13]

In 1809 he began the publication of a landmark three-part treatise titled "On Aerial Navigation" (1809–1810). [14] 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 developed the modern conventional form of the fixed-wing aeroplane having a stabilising tail with both horizontal and vertical surfaces, flying gliders both unmanned and manned.

He introduced the use of the whirling arm test rig to investigate the aerodynamics of flight, using it to discover the benefits of the curved or cambered aerofoil over the flat wing he had used for his first glider. He also identified and described the importance of dihedral, diagonal bracing and drag reduction, and contributed to the understanding and design of ornithopters and parachutes. [3]

Another significant invention was the tension-spoked wheel, which he devised in order to create a light, strong wheel for aircraft undercarriage.

The 19th century

During the 19th century Cayley's ideas were refined, proved and expanded on. Important investigators included Otto Lilienthal and Horatio Phillips.

The 20th century

Pedro Paulet, scientist born in the city of Arequipa, Peru in the year of 1874, was one of the first to experiment with propulsion rockets being considered the «Father of Modern Rocket» and by others as the «Father of Aeronautics Modern ». He developed plans for a "torpedo plane", which is why he is considered ahead of his time. When the internal explosion engines were invented, small enough to be able to propel a flying device with them, a race started between two flight possibilities: the lighter than the air (dirigibles) and the heavier than the air (aeroplanes) .

Branches

The Eurofighter Typhoon. Typhoon f2 zj910 arp.jpg
The Eurofighter Typhoon.
Antonov An-225 Mriya, the largest aeroplane ever built. An-225 Mriya.jpg
Antonov An-225 Mriya, the largest aeroplane ever built.

Aeronautics may be divided into three main branches comprising Aviation, Aeronautical science and Aeronautical engineering.

Aviation

Aviation is the art or practice of aeronautics. Historically aviation meant only heavier-than-air flight, but nowadays it includes flying in balloons and airships.

Aeronautical science

Aeronautical science covers the practical theory of aeronautics and aviation, including operations, navigation, air safety and human factors.

A candidate pilot is likely to study for a qualification in aeronautical science.

≠===Aeronautical engineering===

Aeronautical engineering covers the design and construction of aircraft, including how they are powered, how they are used and how they are controlled for safe operation. [15] it includes salary of 15 to 30 lakhs per annuually.


A major part of aeronautical engineering is aerodynamics, the science of passing through the air.

With the increasing activity in space flight, nowadays aeronautics and astronautics are often combined as aerospace engineering.

Aerodynamics

The science of aerodynamics deals with the motion of air and the way that it interacts with objects in motion, such as an aircraft.

The study of aerodynamics falls broadly into three areas:

Incompressible flow occurs where the air simply moves to avoid objects, typically at subsonic speeds below that of sound (Mach 1).

Compressible flow occurs where shock waves appear at points where the air becomes compressed, typically at speeds above Mach 1.

Transonic flow occurs in the intermediate speed range around Mach 1, where the airflow over an object may be locally subsonic at one point and locally supersonic at another.

Rocketry

Launch of Apollo 15 Saturn V rocket: T - 30 s through T + 40 s.

A rocket or rocket vehicle is a missile, spacecraft, aircraft or other vehicle which obtains thrust from a rocket engine. In all rockets, the exhaust is formed entirely from propellants carried within the rocket before use. [16] Rocket engines work by action and reaction. Rocket engines push rockets forwards simply by throwing their exhaust backwards extremely fast.

Rockets for military and recreational uses date back to at least 13th-century China. [17] Significant scientific, interplanetary and industrial use did not occur until the 20th century, when rocketry was the enabling technology of the Space Age, including setting foot on the moon.

Rockets are used for fireworks, weaponry, ejection seats, launch vehicles for artificial satellites, human spaceflight and exploration of other planets. While comparatively inefficient for low speed use, they are very lightweight and powerful, capable of generating large accelerations and of attaining extremely high speeds with reasonable efficiency.

Chemical rockets are the most common type of rocket and they typically create their exhaust by the combustion of rocket propellant. Chemical rockets store a large amount of energy in an easily released form, and can be very dangerous. However, careful design, testing, construction and use minimizes risks.

See also

Related Research Articles

Unpowered aircraft aerial vehicle capable of sustaining flight without onboard propulsion

Unpowered aircraft can remain airborne for a significant period of time without onboard propulsion. They can be classified as fixed-wing gliders, lighter-than-air balloons and tethered kites. This requires a trajectory that is not merely a vertical descent such as a parachute. In the case of kites, lift is obtained by tethering to a fixed or moving object, perhaps another kite, to obtain a flow of wind over the lifting surfaces. In the case of balloons, lift is obtained through inherent buoyancy and the balloon may or may not be tethered. Free balloon flight has little directional control. Gliding aircraft include sailplanes, hang gliders, and paragliders that have full directional control in free flight.

Blimp non-rigid airship

A blimp, or non-rigid airship, is an airship (dirigible) or barrage balloon without an internal structural framework or a keel. Unlike semi-rigid and rigid airships, blimps rely on the pressure of the lifting gas inside the envelope and the strength of the envelope itself to maintain their shape.

History of aviation history of the design, development, production, operation, and use of aircraft

The history of aviation extends for more than two thousand years, from the earliest forms of aviation such as kites and attempts at tower jumping to supersonic and hypersonic flight by powered, heavier-than-air jets.

Ornithopter aircraft which use flapping movement of the wings to generate lift

An ornithopter is an aircraft that flies by flapping its wings. Designers seek to imitate the flapping-wing flight of birds, bats, and insects. Though machines may differ in form, they are usually built on the same scale as these flying creatures. Manned ornithopters have also been built, and some have been successful. The machines are of two general types: those with engines, and those powered by the muscles of the pilot.

Aerostat lighter than air aircraft

An aerostat is a lighter than air aircraft that gains its lift through the use of a buoyant gas. Aerostats include unpowered balloons and powered airships. A balloon may be free-flying or tethered. The average density of the craft is lower than the density of atmospheric air, because its main component is one or more gasbags, a lightweight skin containing a lifting gas to provide buoyancy, to which other components such as a gondola containing equipment or people are attached. Especially with airships, the gasbags are often protected by an outer envelope.

Balloon (aeronautics) type of aerostat that remains aloft due to its buoyancy

In aeronautics, a balloon is an unpowered aerostat, which remains aloft or floats due to its buoyancy. A balloon may be free, moving with the wind, or tethered to a fixed point. It is distinct from an airship, which is a powered aerostat that can propel itself through the air in a controlled manner.

This is a list of aviation-related events during the 18th century :

This is a list of aviation-related events during the 19th century :

Early flying machines

Early flying machines include all forms of aircraft studied or constructed before the development of the modern aeroplane by 1910. The story of modern flight begins more than a century before the first successful manned aeroplane, and the earliest aircraft thousands of years before.

Hybrid airship partially aero-static aircraft

A hybrid airship is a powered aircraft that obtains some of its lift as a lighter-than-air (LTA) airship and some from aerodynamic lift as a heavier-than-air aerodyne.

Alphonse Pénaud French engineer

Alphonse Pénaud, was a 19th-century French pioneer of aviation design and engineering. He was the originator of the use of twisted rubber to power model aircraft, and his 1871 model airplane, which he called the Planophore, was the first aerodynamically stable flying model. He went on to design a full sized aircraft with many advanced features, but was unable to get any support for the project, and eventually committed suicide in 1880, aged 30.

Thermal airship airship

A thermal airship is an airship that generates buoyancy by heating air in a large chamber or envelope. The lower density of interior hot air compared to cool ambient air causes an upward force on the envelope. This is very similar to a hot air balloon, with the notable exception that an airship has a powered means of propulsion, whilst a hot air balloon relies on winds for navigation. An airship that uses steam would also qualify as a thermal airship.

James D. DeLaurier is an inventor and professor emeritus of the University of Toronto Institute for Aerospace Studies. He is a leader in design and analysis of lighter than air vehicles and flapping winged aircraft.

History of ballooning

The history of ballooning, both with hot air and gas, spans many centuries. It includes many firsts, including the first human flight, first flight across the English Channel, first flight in North America, and first aircraft related disaster.

Because of Archimedes' principle, a lifting gas is required for aerostats to create buoyancy, particularly in Lighter-than-air aircraft, which include free balloons, moored balloons, and airships. Only certain lighter than air gases are suitable as lifting gases. Dry air has a density of about 1.29 g/L at standard conditions for temperature and pressure (STP) and an average molecular mass of 28.97 g/mol, and so lighter than air gases have a density lower than this.

Aerospace engineering branch of engineering

Aerospace engineering is the primary field of engineering concerned with the development of aircraft and spacecraft. It has two major and overlapping branches: aeronautical engineering and astronautical engineering. Avionics engineering is similar, but deals with the electronics side of aerospace engineering.

Most of the terms listed in Wikipedia glossaries are already defined and explained within Wikipedia itself. However, glossaries like this one are useful for looking up, comparing and reviewing large numbers of terms together. You can help enhance this page by adding new terms or writing definitions for existing ones.

References

Citations

  1. A Learned and Professional Society Archived 2014-02-09 at the Wayback Machine (Retrieved 8 March 2014)
  2. 1 2 Aeronautics. 1. Grolier. 1986. p. 226.
  3. 1 2 3 Wragg 1974.
  4. Pelham, D.; The Penguin book of kites, Penguin (1976)
  5. Wragg 1974, pp. 10–11.
  6. Wragg 1974, p. 11.
  7. Fairlie & Cayley 1965, p. 163.
  8. Ege 1973, p. 6.
  9. Ege 1973, p. 7.
  10. Ege 1973, pp. 97–100.
  11. Ege 1965, p. 105.
  12. Fairlie & Cayley 1965.
  13. "Sir George Carley". Flyingmachines.org. Archived from the original on 2009-02-11. Retrieved 2009-07-26. Sir George Cayley is one of the most important people in the history of aeronautics. Many consider him the first true scientific aerial investigator and the first person to understand the underlying principles and forces of flight.
  14. Cayley, George. "On Aerial Navigation" Part 1 Archived 2013-05-11 at the Wayback Machine , Part 2 Archived 2013-05-11 at the Wayback Machine , Part 3 Archived 2013-05-11 at the Wayback Machine Nicholson's Journal of Natural Philosophy, 1809–1810. (Via NASA). Raw text Archived 2016-03-03 at the Wayback Machine . Retrieved: 30 May 2010.
  15. Aeronautical engineering Archived 2012-07-27 at the Wayback Machine , University of Glasgow.
  16. Sutton, George (2001). "1". Rocket Propulsion Elements (7th ed.). Chichester: John Wiley & Sons. ISBN   978-0-471-32642-7.
  17. MSFC History Office "Rockets in Ancient Times (100 B.C. to 17th Century)"

Sources

  • Ege, L. (1973). Balloons and airships. Blandford.
  • Fairlie, Gerard; Cayley, Elizabeth (1965). The life of a genius. Hodder and Stoughton.
  • Wragg, D.W. (1974). Flight before flying. Osprey. ISBN   978-0850451658.

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