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Balloon (aircraft)
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- "Ballooning" redirects here. For the behavior of spiders and other arthropods, see Ballooning (spider).
A balloon is a type of aircraft that remains aloft due to its buoyancy. A balloon travels by moving with the wind. It is distinct from an airship, which is a buoyant aircraft that can be propelled through the air in a controlled manner.
Types of balloon aircraftThere are three main types of balloon aircraft:
- Hot air balloons obtain their buoyancy by heating the air inside the balloon. They are the most common type of balloon aircraft. "Hot air balloon" is sometimes used incorrectly to denote any balloon that carries people.
- Gas balloons are inflated with a gas of lower molecular weight than the ambient atmosphere. Most gas balloons operate with the internal pressure of the gas being the same as the pressure of the surrounding atmosphere. There is a type of gas balloon, called a superpressure balloon, that can operate with the lifting gas at pressure that exceeds the pressure of the surrounding air, with the objective of limiting or eliminating the loss of gas from day-time heating. Gas balloons are filled with gases such as:
- hydrogen - not widely used for aircraft since the Hindenburg disaster because of high flammability (except for some sport balloons as well as nearly all unmanned scientific and weather balloons).
- helium - the gas used today for all airships and most manned balloons.
- ammonia - used infrequently due to its caustic qualities and limited lift.
- coal gas - used in the early days of ballooning; it is highly flammable.
- Rozière balloons use both heated and unheated lifting gases. The most common modern use of this type of balloon is for long-distance record flights such as the recent circumnavigations.
History
The hot air balloon Kongming lantern was developed for military communications around the second or third century AD in China. It is thought that some ancient civilizations may have developed manned hot air balloon flight. For example, the Nazca lines (which are best seen from the air) allegedly presuppose some form of manned flight, such as a balloon.
In 1710 in Lisbon, Bartolomeu de Gusmão made a balloon filled with heated air rise inside a room. He also made a balloon named Passarola and attempted to lift himself from Saint George Castle in Lisbon, but only managed to harmlessly fall about one kilometre away. According to the Portuguese speaking community, this was the first man ever to fly in human history. However, this claim is not generally recognized by aviation historians outside the Portuguese speaking community, in particular the FAI.
Following Henry Cavendish's 1766 work on hydrogen, Joseph Black proposed that a balloon filled with hydrogen would be able to rise in the air.
The first recorded manned flight was made in a hot air balloon built by the Montgolfier brothers on November 21 1783. The flight started in Paris and reached a height of 500 feet or so. The pilots, Jean-François Pilâtre de Rozier and Francois Laurent (the Marquis of d'Arlandes), covered about 5 1/2 miles in 25 minutes.
Only a few days later, on December 1 1783, Professor Jacques Charles and Nicholas Louis Robert made the first gas balloon flight, also from Paris. The hydrogen filled balloon flew to almost 2,000 feet (600 m), stayed aloft for over 2 hours and covered a distance of 27 miles (43 km), landing in the small town of Nesle.
The first aircraft disaster occurred in May 1785 when the town of Tullamore, County Offaly, Ireland was seriously damaged when the crash of a balloon resulted in a fire that burned down about 100 houses, making the town home to the world's first aviation disaster. To this day, the town shield depicts a phoenix rising from the ashes.
Blanchard went on to make the first manned flight of a balloon in America on January 9 1793. His hydrogen filled balloon took off from a prison yard in Philadelphia, Pennsylvania. The flight reached 5,800 feet (1,770 m) and landed in Gloucester County, New Jersey. President George Washington was among the guests observing the takeoff.
Gas balloons became the most common type from the 1790s until the 1960s.
The first steerable balloon (also known as a dirigible) was flown by Henri Giffard in 1852. Powered by a steam engine, it was too slow to be effective. Like heavier than air flight, the internal combustion engine made dirigibles – especially blimps – practical, starting in the late 19th century. In 1872 Paul Haenlein flew the first (tethered) internal combustion motor powered balloon. The first to fly in an untethered airship powered by an internal combustion engine was Alberto Santos Dumont in 1898.
Henri Giffardalso developed a tethered balloon for passengers in 1878 in the Tuileries Garden in Paris. The first tethered balloon in modern times was made in France at Chantilly Castle in 1994 by AEROPHILE S.A.
Ed Yost redesigned the hot air balloon in the late 1950s using rip-stop nylon fabrics and high-powered propane burners to create the modern hot air balloon. His first flight of such a balloon, lasting 25 minutes and covering 3 miles (5 km), occurred on October 22 1960 in Bruning, Nebraska. Yost's improved design for hot air balloons triggered the modern sport balloon movement. Today, hot air balloons are much more common than gas balloons.
Balloons as flying machinesA balloon is conceptually the simplest of all flying machines. The balloon is a fabric envelope filled with a gas that is lighter than the surrounding atmosphere. As the entire balloon is less dense than its surroundings, it rises, taking along with it a basket, attached underneath, that carries passengers or payload. Although a balloon has no propulsion system, a degree of directional control is possible through making the balloon rise or sink in altitude to find favorable wind directions.
The first balloons capable of carrying passengers used hot air to obtain buoyancy and were built by the brothers Josef and Etienne Montgolfier in Annonay, France.
Balloons using the light gas hydrogen for buoyancy were flown less than a month later. They were invented by Professor Jacques Charles and first flown on December 1 1783. Gas balloons have greater lift and can be flown much longer than hot air, so gas balloons dominated ballooning for the next 200 years. In the 19th century, it was common to use town gas to fill balloons; it was not as light as pure hydrogen gas, but was much cheaper and readily available.
The third balloon type was invented by Pilâtre de Rozier and is a hybrid of a hot air and a gas balloon. Gas balloons have an advantage of being able to fly for a long time, and hot air balloons have an advantage of being able to easily change altitude, so the Rozier balloon was a hydrogen balloon with a separate hot air balloon attached. In 1785, Pilâtre de Rozier took off in an attempt to fly across the English Channel, but the balloon exploded a half-hour into the flight. This accident earned de Rozier the title "The First to Fly and the First to Die". It wasn't until the 1980s that technology once again allowed the Rozier balloons to become feasible.
Jean-Pierre Blanchard made the first piloted balloon flight in North America on January 9 1793.
Both the hot air, or Montgolfière, balloon and the gas balloon are still in common use. Montgolfière balloons are relatively inexpensive as they do not require high-grade materials for their envelopes, and they are popular for balloonist sport activity.
A new way of flying in a gas balloon is with a tether. Notable balloons are in Paris since 1999, in Berlin since 2000, in Disneyland Resort Paris since 2005 with more than 100 000 passengers per year, and the DHL Balloon in Singapore since 2006. All of them have been made by Aerophile SA. Aerophile Balloon is also operated in the San Diego Wild Animal Park in California which has been in operation since the year 2005.
Light gas balloons are predominant in scientific applications, as they are capable of reaching much higher altitudes for much longer periods of time. They are generally filled with helium. Although hydrogen has more lifting power, it is explosive in an atmosphere full of oxygen. With a few exceptions, scientific balloon missions are unmanned.
There are two types of light-gas balloons: zero-pressure and superpressure. Zero-pressure balloons are the traditional form of light-gas balloon. They are partially inflated with the light gas before launch, with the gas pressure the same both inside and outside the balloon. As the zero-pressure balloon rises, its gas expands to maintain the zero pressure difference, and the balloon's envelope swells.
At night, the gas in a zero-pressure balloon cools and contracts, causing the balloon to sink. A zero-pressure balloon can only maintain altitude by releasing gas when it goes too high, where the expanding gas can threaten to rupture the envelope, or releasing ballast when it sinks too low. Loss of gas and ballast limits the endurance of zero-pressure balloons to a few days.
A superpressure balloon, in contrast, has a tough and inelastic envelope that is filled with light gas to pressure higher than that of the external atmosphere, and then sealed. The superpressure balloon cannot change size greatly, and so maintains a generally constant volume. The superpressure balloon maintains an altitude of constant density in the atmosphere, and can maintain flight until gas leakage gradually brings it down.
Superpressure balloons offer flight endurance of months, rather than days. In fact, in typical operation an Earth-based superpressure balloon mission is ended by a command from ground control to open the envelope, rather than by natural leakage of gas.
For air transport balloons must contain a gas lighter than the surrounding air. There are two types:
- Hot air balloons: filled with hot air, which by heating becomes lighter than the surrounding air; they have been used to carry human passengers since the 1790s;
- Balloons filled with:
Large helium balloons are used as high flying vessels to carry scientific instruments (as do weather balloons), or even human passengers with a tether like in Paris, Berlin, Hong Kong or Singapore.
Cluster ballooning uses many smaller gas-filled balloons for flight (see ).
Balloons in the militaryThe first military use of a balloon was at the Battle of Fleurus in 1794, when L'Entreprenant was used by French Revolutionary troops to watch the movements of the enemy. On April 2 1794, an aeronauts corps was created in the French army; however, given the logistical problems linked with the production of hydrogen on the battlefield (it required constructing ovens and pouring water on white-hot iron), the corps was disbanded in 1799.
American Civil WarThe first major-scale use of balloons in the military occurred during the American Civil War with the Union Army Balloon Corps established and organized by Prof. Thaddeus S. C. Lowe in the summer of 1861. Originally, the balloons were inflated with coal gas from municipal services and then walked out to the battlefield, an arduous and inefficient operation as the balloons had to be returned to the city every four days for re-inflation. Eventually hydrogen gas generators, a compact system of tanks and copper plumbing, were constructed which converted the combining of iron filings and sulfuric acid to hydrogen. The generators were easily transported with the uninflated balloons to the field on a standard buckboard. In all, Lowe built seven balloons that were fit for military service.
The first application thought useful for balloons was map-making from aerial vantage points, thus Lowe's first assignment was with the Topographical Engineers. General Irvin McDowell, commander of the Army of the Potomac, realized their value in aerial reconnaissance and had Lowe, who at the time was using his personal balloon the Enterprise, called up to the First Battle of Bull Run. Lowe also worked as a Forward Artillery Observer (FAO) by directing artillery fire via flag signals. This enabled gunners on the ground to fire accurately at targets they could not see, a military first.
Lowe's first military balloon, the Eagle was ready by October 1 1861. It was called into service immediately to be towed to Lewinsville, Virginia, without any gas generator which took longer to build. The trip began after inflation in Washington, D.C. and turned into a 12 mile (19 km), 12-hour excursion that was upended by a gale force wind which ripped the aerostat from its netting and sent it sailing to the coast. Balloon activities were suspended until all balloons and gas generators were completed.
With his ability to inflate balloons from remote stations, Lowe, his new balloon the Washington and two gas generators were loaded onto a converted coal barge the George Washington Parke Custis. As he was towed down the Potomac, Lowe was able to ascend and observe the battlefield as it moved inward on the heavily forested peninsula. This would be the military's first claim of an aircraft carrier.
The Union Army Balloon Corps enjoyed more success in the battles of the Peninsula Campaign than the Army of the Potomac it sought to support. The general military attitude toward the use of balloons deteriorated, and by August 1863 the Balloon Corps was disbanded.
The Confederate Army also made use of balloons, but they were gravely hampered by supplies due to the embargoes. They were forced to fashion their balloons from colored silk dress-making material, and their use was limited by the infrequent supply of gas in Richmond, Virginia. By the summer of 1863, all balloon reconnaissance of the Civil War had ceased.
In other countriesIn Britain during July 1863, experimental balloon ascents for reconnaissance purposes were conducted by the Royal Engineers on behalf of the British Army, but although the experiments were successful it was considered not worth pursuing further because it was too expensive. However by 1888 a School of Ballooning was established at Chatham, Medway, Kent. It moved to Stanhope Lines, Aldershot in 1890 when a balloon section and depot were formed as permanent units of the Royal Engineers establishment.
During the Paraguayan War, balloons were also used for observation by the Brazilian Army.
Balloons were used by the Royal Engineers for reconnaissance and observation purposes during the Bechuanaland Expedition (1885), the Sudan Expedition (1885) and during the Anglo-Boer War (1899-1902). On October 5 1907 Colonel John Capper (late Royal Engineers) and team flew the military airship Nulli Secundus from Farnborough round St Paul's Cathedral in London and back with a view to raising public interest.
Hydrogen-filled balloons were also widely used during World War I (1914-1918) to detect enemy troop movements and to direct artillery fire. Observers phoned their reports to officers on the ground who then relayed the information to those who needed it. Balloons were frequently targets of opposing aircraft. Planes assigned to attack enemy balloons were often equipped with incendiary bullets, for the purpose of igniting the hydrogen.
The Aeronaut Badge was established by the United States Army in World War I to denote service members who were qualified balloon pilots. Observation balloons were retained well after the Great War, being used in the Russo-Finnish conflicts.
The Japanese launched thousands of balloon bombs to the US and Canada, carried in the jet stream; see fire balloon. The British used balloons to carry incendiary devices to Germany between 1942 and 1944; see Operation Outward.
RecordsOn May 27 1931, Auguste Piccard and Paul Kipfer became the first to reach the stratosphere in a balloon.
On August 31 1933, Alexander Dahl took the first picture of the earth's curvature in an open hydrogen gas balloon.
The altitude record for a manned balloon was set at 34,668 meters on May 4 1961 by Malcolm Ross and Victor Prather in the Stratolab V balloon payload launched from the deck of the USS Antietam in the Gulf of Mexico.
The altitude record for an unmanned balloon is 53.0 kilometres, reached with a volume of 60,000 cubic metres. The balloon was launched by JAXA in May 25 2002 from Iwate Prefecture, Japan. This is the greatest height ever obtained by an atmospheric vehicle. Only rockets, rocket planes, and ballistic projectiles have flown higher.
Balloons in spaceThe Echo satellite was a balloon launched by rocket in 1960 and used for passive relay of radio communication.
In 1984 the Soviet space probes Vega 1 and Vega 2 released two balloons with scientific experiments in the atmosphere of Venus. They transmitted signals for two days to Earth.
Ballons in literatureJules Verne wrote a non fiction story about being stranded in a hydrogen balloon, see
See alsoExternal links- - learn the dynamics of a hot air balloon on the Internet based simulator.
- Historical recompilation project on the use of stratospheric balloons in the scientific research, the military field and the aerospace activity
- Royal Engineers and Aeronautics
- Early British Military Ballooning (1863)
- The biggest Balloon Company of the world in Cappadocia
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