HOME

TheInfoList



OR:

A hot air balloon is a
lighter-than-air A lifting gas or lighter-than-air gas is a gas that has a density lower than normal atmospheric gases and rises above them as a result. It is required for aerostats to create buoyancy, particularly in lighter-than-air aircraft, which include fre ...
aircraft consisting of a bag, called an envelope, which contains heated air. Suspended beneath is a
gondola The gondola (, ; vec, góndoła ) is a traditional, flat-bottomed Venetian rowing boat, well suited to the conditions of the Venetian lagoon. It is typically propelled by a gondolier, who uses a rowing oar, which is not fastened to the hull, ...
or
wicker basket Wicker is the oldest furniture making method known to history, dating as far back as 5,000 years ago. It was first documented in ancient Egypt using pliable plant material, but in modern times it is made from any pliable, easily woven material. ...
(in some long-distance or high-altitude balloons, a capsule), which carries passengers and a source of heat, in most cases an open flame caused by burning liquid propane. The heated air inside the envelope makes it
buoyant Buoyancy (), or upthrust, is an upward force exerted by a fluid that opposes the weight of a partially or fully immersed object. In a column of fluid, pressure increases with depth as a result of the weight of the overlying fluid. Thus the pr ...
, since it has a lower density than the colder air outside the envelope. As with all
aircraft An aircraft is a vehicle 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 engine ...
, hot air balloons cannot fly beyond the atmosphere. The envelope does not have to be sealed at the bottom, since the air inside the envelope is at about the same pressure as the surrounding air. In modern sport balloons the envelope is generally made from
nylon Nylon is a generic designation for a family of synthetic polymers composed of polyamides ( repeating units linked by amide links).The polyamides may be aliphatic or semi-aromatic. Nylon is a silk-like thermoplastic, generally made from pe ...
fabric, and the inlet of the balloon (closest to the burner flame) is made from a fire-resistant material such as
Nomex Nomex is a flame-resistant meta-aramid material developed in the early 1960s by DuPont and first marketed in 1967. Properties Nomex and related aramid polymers are related to nylon, but have aromatic backbones, and hence are more rigid and mo ...
. Modern balloons have been made in many shapes, such as rocket ships and the shapes of various commercial products, though the traditional shape is used for most non-commercial and many commercial applications. The hot air balloon is the first successful human-carrying
flight Flight or flying is the process by which an object moves through a space without contacting any planetary surface, either within an atmosphere (i.e. air flight or aviation) or through the vacuum of outer space (i.e. spaceflight). This can be a ...
technology. The first untethered manned hot air balloon flight was performed by
Jean-François Pilâtre de Rozier Jean-François Pilâtre de Rozier () was a French chemistry and physics teacher, and one of the first pioneers of aviation. He made the first manned free balloon flight with François Laurent d'Arlandes on 21 November 1783, in a Montgolfier bal ...
and François Laurent d'Arlandes on November 21, 1783, in
Paris Paris () is the Capital city, capital and List of communes in France with over 20,000 inhabitants, most populous city of France, with an estimated population of 2,165,423 residents in 2019 in an area of more than 105 km² (41 sq mi), ma ...
, France, in a balloon created by the
Montgolfier brothers The Montgolfier brothers – Joseph-Michel Montgolfier (; 26 August 1740 – 26 June 1810) and Jacques-Étienne Montgolfier (; 6 January 1745 – 2 August 1799) – were aviation pioneers, balloonists and paper manufacturers from the commune A ...
. The first hot air balloon flown in the Americas was launched from the Walnut Street Jail in Philadelphia on January 9, 1793, by the French aeronaut
Jean Pierre Blanchard Jean-Pierre rançoisBlanchard (4 July 1753 – 7 March 1809) was a French inventor, best known as a pioneer of gas balloon flight, who distinguished himself in the conquest of the air in a balloon, in particular the first crossing of the Englis ...
. Hot air balloons that can be propelled through the air rather than simply drifting with the
wind Wind is the natural movement of air or other gases relative to a planet's surface. Winds occur on a range of scales, from thunderstorm flows lasting tens of minutes, to local breezes generated by heating of land surfaces and lasting a few ho ...
are known as thermal airships.


History


Premodern and unmanned balloons

A precursor of the hot air balloon was the
sky lantern A sky lantern (), also known as Kǒngmíng lantern (), or Chinese lantern, is a small hot air balloon made of paper, with an opening at the bottom where a small fire is suspended. In Asia and elsewhere around the world, sky lanterns have bee ...
().
Zhuge Liang Zhuge Liang ( zh, t=諸葛亮 / 诸葛亮) (181 – September 234), courtesy name Kongming, was a Chinese statesman and military strategist. He was chancellor and later regent of the state of Shu Han during the Three Kingdoms period. He is ...
of the Shu Han kingdom, during the
Three Kingdoms The Three Kingdoms () from 220 to 280 AD was the tripartite division of China among the dynastic states of Cao Wei, Shu Han, and Eastern Wu. The Three Kingdoms period was preceded by the Eastern Han dynasty and was followed by the West ...
era (220–280 CE), used these airborne lanterns for military signaling. In the 18th century the Portuguese Jesuit priest
Bartolomeu de Gusmão Bartolomeu Lourenço de Gusmão (December 1685 – 18 November 1724) was a Brazilian-born Portuguese priest and naturalist, who was a pioneer of lighter-than-air airship design. Early life Gusmão was born at Santos, then part of the Portugue ...
envisioned an aerial apparatus called , which was the predecessor of the hot air balloon. The purpose of was to serve as air vessel in order to facilitate communication and as a strategical device. In 1709
John V of Portugal Dom John V ( pt, João Francisco António José Bento Bernardo; 22 October 1689 – 31 July 1750), known as the Magnanimous (''o Magnânimo'') and the Portuguese Sun King (''o Rei-Sol Português''), was King of Portugal from 9 December 17 ...
decided to fund Bartolomeu de Gusmão's project following a petition made by the Jesuit priest, and an unmanned demonstration was performed at Casa da India in presence of John V, the queen
Maria Anna of Austria Maria Anna of Austria (Maria Anna Josepha Antonia Regina; 7 September 1683 – 14 August 1754) was Queen of Portugal as the wife of King John V of Portugal. She served as the regent of Portugal from 1742 until 1750 during the illness of her hus ...
, having as witnesses the Italian cardinal Michelangelo Conti, two members of the Portuguese Royal Academy of History, one Portuguese diplomat and one chronicler. This event would bring some European attention to this event and this project. A later article dated on October 20, 1786, by the London ''Daily Universal Register'' would state that the inventor was able to raise himself by the use of his prototype. Also in 1709, the Portuguese Jesuit wrote (''Short Manifesto for those who are unaware that is possible to sail through the element air''); he also left designs for a manned air vessel. The notable balloonist
Julian Nott Julian Franklin Keith Nott (born 23 August 1960) is a British composer and conductor, mostly of animated films. He is known for his work on ''Wallace and Gromit'' and ''Peppa Pig''. Biography Nott was born in Marylebone, London, and was edu ...
, in the 1970s; hypothesized that two millennia ago, the
Nazca Lines The Nazca Lines are a group of geoglyphs made in the soil of the Nazca Desert in southern Peru. They were created between 500 BCE and 500 CE by people making depressions or shallow incisions in the desert floor, removing pebbles and l ...
geoglyph A geoglyph is a large design or motif (generally longer than 4 metres) produced on the ground by durable elements of the landscape, such as stones, stone fragments, gravel, or earth. A positive geoglyph is formed by the arrangement and alignmen ...
s' creation could have been guided by Nazca leaders in a balloon, possibly the earliest hot air balloon flights in human history. In 1975 to support this theory, he designed and piloted the Nazca Prehistoric Balloon, claiming to have used only methods and materials available to the Pre-Inca Peruvians 1,000 years ago.


First manned flight

The French brothers Joseph-Michel and Jacques-Étienne
Montgolfier The Montgolfier brothers – Joseph-Michel Montgolfier (; 26 August 1740 – 26 June 1810) and Jacques-Étienne Montgolfier (; 6 January 1745 – 2 August 1799) – were aviation pioneers, balloonists and paper manufacturers from the commune A ...
developed a hot-air balloon in Annonay, Ardeche, France, and demonstrated it publicly on September 19, 1783, making an unmanned flight lasting 10 minutes. After experimenting with unmanned balloons and flights with animals, the first balloon flight with humans aboard, a tethered flight, performed on or around October 15, 1783, by Jean-Francois Pilatre de Rozier, who made at least one tethered flight from the yard of the Reveillon workshop in the
Faubourg Saint-Antoine The Faubourg Saint-Antoine was one of the traditional suburbs of Paris, France. It grew up to the east of the Bastille around the abbey of Saint-Antoine-des-Champs, and ran along the Rue du Faubourg Saint-Antoine. Location The Faubourg Saint-An ...
. Later that same day, Pilatre de Rozier became the second human to ascend into the air, reaching an altitude of , the length of the tether. The first free flight with human passengers was made a few weeks later, on November 21, 1783. King Louis XVI had originally decreed that condemned criminals would be the first pilots, but de Rozier, along with Marquis François d'Arlandes, petitioned successfully for the honor. The first military use of a hot air balloon happened in 1794 during the battle of Fleurus, when the French used the balloon for observation.
Jean-Pierre Blanchard Jean-Pierre rançoisBlanchard (4 July 1753 – 7 March 1809) was a French inventor, best known as a pioneer of gas balloon flight, who distinguished himself in the conquest of the air in a balloon, in particular the first crossing of the Englis ...
became the first person to fly a hot air balloon in various countries, including the United States, the Netherlands, and Germany. His most notable flight crossed the
English Channel The English Channel, "The Sleeve"; nrf, la Maunche, "The Sleeve" (Cotentinais) or ( Jèrriais), (Guernésiais), "The Channel"; br, Mor Breizh, "Sea of Brittany"; cy, Môr Udd, "Lord's Sea"; kw, Mor Bretannek, "British Sea"; nl, Het Kana ...
heading to the
Dover Castle Dover Castle is a medieval castle in Dover, Kent, England and is Grade I listed. It was founded in the 11th century and has been described as the "Key to England" due to its defensive significance throughout history. Some sources say it is the ...
accompanied by Dr. 
John Jeffries John Jeffries (5 February 1744 – 16 September 1819) was an American physician, scientist, and military surgeon with the British Army in Nova Scotia and New York during the American Revolution. He is best known for accompanying French invent ...
, which occurred on 7 January 1785. In 1808, Blanchard suffered a heart attack while ballooning above The Hague, fell from his balloon, and experienced fatal injuries. His wife
Sophie Blanchard Sophie Blanchard (25 March 1778 – 6 July 1819), commonly referred to as Madame Blanchard and also known by many combinations of her maiden and married names, including Madeleine-Sophie Blanchard, Marie Madeleine-Sophie Blanchard, Marie Sophie ...
continued his profession, but also died a decade later on a balloon, due to a firework festival causing the hydrogen in the balloon to be set on fire.


Modern balloons

Modern hot air balloons, with an onboard heat source, were developed by
Ed Yost Paul Edward Yost (June 30, 1919 – May 27, 2007) was the American inventor of the modern hot air balloon and is referred to as the "Father of the Modern Day Hot-Air Balloon." He worked for a high-altitude research division of General Mill ...
, beginning during the 1950s; his work resulted in his first successful flight on October 22, 1960. The first modern hot air balloon to be made in the United Kingdom (UK) was the Bristol Belle, built in 1967. Presently, hot air balloons are used primarily for recreation.


Records

Hot air balloons are able to fly to extremely high altitudes. On November 26, 2005 Vijaypat Singhania set the world altitude record for highest hot air balloon flight, reaching . He took off from downtown
Mumbai Mumbai (, ; also known as Bombay — List of renamed Indian cities and states#Maharashtra, the official name until 1995) is the capital city of the Indian States and union territories of India, state of Maharashtra and the ''de facto'' fin ...
, India, and landed south in Panchale. The previous record of had been set by Per Lindstrand on June 6, 1988, in
Plano, Texas Plano ( ) is a city in Collin County and Denton County, Texas, United States. It had a population of 285,494 at the 2020 census. It is a principal city of the Dallas–Fort Worth metroplex. History European settlers came to the area near ...
. On January 15, 1991, the ''Virgin Pacific Flyer'' balloon completed the longest flight in a hot air balloon, when Per Lindstrand (born in Sweden, but resident in the UK) and Richard Branson of the UK flew from Japan to Northern Canada. With a volume of 74,000 cubic meters (2.6 million cubic feet), the balloon envelope was the largest ever built for a hot air craft. Designed to fly in the trans-oceanic jet streams, the ''
Pacific Flyer The Pacific Ocean is the largest and deepest of Earth's five oceanic divisions. It extends from the Arctic Ocean in the north to the Southern Ocean (or, depending on definition, to Antarctica) in the south, and is bounded by the continen ...
'' recorded the fastest ground speed for a manned balloon at . The longest duration record was set by Swiss psychiatrist
Bertrand Piccard Bertrand Piccard FRSGS (born 1 March 1958) is a Swiss explorer, psychiatrist and environmentalist. Along with Brian Jones, he was the first to complete a non-stop balloon flight around the globe, in a balloon named Breitling Orbiter 3. He was ...
( Auguste Piccard's grandson) and Briton Brian Jones, flying in the Breitling Orbiter 3. It was the first nonstop trip around the world by balloon. The balloon left Château-d'Oex, Switzerland, on March 1, 1999, and landed at 1:02 a.m. on March 21 in the Egyptian desert south of Cairo. The two men exceeded distance, endurance, and time records, traveling 19 days, 21 hours, and 55 minutes.
Steve Fossett James Stephen Fossett (April 22, 1944 – September 3, 2007) was an American businessman and a record-setting aviator, sailor, and adventurer. He was the first person to fly solo nonstop around the world in a balloon and in a fixed-wing aircraf ...
, flying solo, exceeded the record for briefest time traveling around the world on 3 July 2002 on his sixth attempt, in 320 h 33 min. Steve Fossett and Fedor Konyukhov, both sub-class AM-15. Fedor Konyukhov flew solo round the world on his first attempt in a hybrid hot air/helium balloon from 11 to 23 July 2016 for a round-the world time of 268 h 20 min.


Construction

A hot air balloon for manned flight uses a single-layered, fabric gas bag (lifting "envelope"), with an opening at the bottom called the mouth or throat. Attached to the envelope is a basket, or gondola, for carrying the passengers. Mounted above the basket and centered in the mouth is the "burner", which injects a flame into the envelope, heating the air within. The heater or burner is fueled by propane, a
liquefied gas Liquefied gas (sometimes referred to as liquid gas) is a gas that has been turned into a liquid by cooling or compressing it. Examples of liquefied gases include liquid air, liquefied natural gas, and liquefied petroleum gas. Liquid air At the ...
stored in pressure vessels, similar to high-pressure forklift cylinders.


Envelope

Modern hot air balloons are usually made of materials such as
ripstop nylon __NOTOC__ Ripstop fabrics are woven fabrics, often made of nylon, using a reinforcing technique that makes them more resistant to tearing and ripping. During weaving, stronger (and often thicker) reinforcement yarns are interwoven at regular inte ...
or
dacron Polyethylene terephthalate (or poly(ethylene terephthalate), PET, PETE, or the obsolete PETP or PET-P), is the most common thermoplastic polymer resin of the polyester family and is used in fibres for clothing, containers for liquids and foo ...
(a polyester). During the manufacturing process, the material is cut into panels and sewn together, along with structural load tapes that carry the weight of the gondola or basket. The individual sections, which extend from the throat to the crown (top) of the envelope, are known as gores or gore sections. Envelopes can have as few as 4 gores or as many as 24 or more. Envelopes often have a crown ring at their very top. This is a hoop of smooth metal, usually aluminium, and approximately in diameter. Vertical load tapes from the envelope are attached to the crown ring. At the bottom of the envelope the vertical load tapes are sewn into loops that are connected to cables (one cable per load tape). These cables, often referred to as
flying wires In aeronautics, bracing comprises additional structural members which stiffen the functional airframe to give it rigidity and strength under load. Bracing may be applied both internally and externally, and may take the form of strut, which act in ...
, are connected to the basket by
carabiner A carabiner or karabiner () is a specialized type of shackle, a metal loop with a spring-loaded gate used to quickly and reversibly connect components, most notably in safety-critical systems. The word is a shortened form of ''Karabinerhaken'' ...
s.


Seams

The most common technique for sewing panels together is called the ''French felled'', ''French fell'', or ''double lap'' seam. The two pieces of fabric are folded over on each other at their common edge, possibly with a load tape as well, and sewn together with two rows of parallel stitching. Other methods include a ''flat lap'' seam, in which the two pieces of fabric are held together simply with two rows of parallel stitching, and a ''zigzag'', where parallel zigzag stitching holds a double lap of fabric.


Coatings

The fabric (or at least part of it, the top 1/3, for example) may be coated with a sealer, such as silicone or
polyurethane Polyurethane (; often abbreviated PUR and PU) refers to a class of polymers composed of organic units joined by carbamate (urethane) links. In contrast to other common polymers such as polyethylene and polystyrene, polyurethane is produced from ...
, to make it impermeable to air. It is often the degradation of this coating and the corresponding loss of impermeability that ends the effective life of an envelope, not weakening of the fabric itself. Heat, moisture, and mechanical wear-and-tear during set-up and pack-up are the primary causes of degradation. Once an envelope becomes too
porous Porosity or void fraction is a measure of the void (i.e. "empty") spaces in a material, and is a fraction of the volume of voids over the total volume, between 0 and 1, or as a percentage between 0% and 100%. Strictly speaking, some tests measure ...
to fly, it may be retired and discarded or perhaps used as a "rag bag": cold-inflated and opened for children to run through. Products for recoating the fabric are becoming available commercially.


Sizes and capacity

A range of envelope sizes is available. The smallest, one-person, basket-less balloons (called "
Hoppers Hopper or hoppers may refer to: Places *Hopper, Illinois * Hopper, West Virginia * Hopper, a mountain and valley in the Hunza–Nagar District of Pakistan * Hopper (crater), a crater on Mercury People with the name * Hopper (surname) * Grace H ...
" or "Cloudhoppers") have as little as of envelope volume; for a perfect sphere the radius would be around . At the other end of the scale, balloons used by commercial sightseeing operations may be able to carry well over two dozen people, with envelope volumes of up to . The most-used size is about , allowing to carry 3 to 5 people.


Vents

The top of the balloon usually has a vent of some sort, enabling the pilot to release hot air to slow an ascent, start a descent, or increase the rate of descent, usually for landing. Some hot air balloons have ''turning vents'', which are side vents that, when opened, cause the balloon to rotate. Such vents are particularly useful for balloons with rectangular baskets, to facilitate aligning the wider side of the basket for landing. The most common type of top vent is a disk-shaped flap of fabric called a ''parachute vent'', invented by Tracy Barnes. The fabric is connected around its edge to a set of "vent lines" that converge in the center. (The arrangement of fabric and lines roughly resembles a parachute—thus the name.) These "vent lines" are themselves connected to a control line that runs to the basket. A parachute vent is opened by pulling on the control line. Once the control line is released, the pressure of the remaining hot air pushes the vent fabric back into place. A parachute vent can be opened briefly while in flight to initiate a rapid descent. (Slower descents are initiated by allowing the air in the balloon to cool naturally.) The vent is pulled open completely to collapse the balloon after landing. An older, and presently less commonly used, style of top vent is called a "
Velcro Velcro, officially known as Velcro IP Holdings LLC and trading as Velcro Companies, is a British privately held company, founded by Swiss electrical engineer George de Mestral in the 1950s. It is the original manufacturer of hook-and-loop fast ...
-style" vent. This too is a disk of fabric at the top of the balloon. However, rather than having a set of "vent lines" that can repeatedly open and close the vent, the vent is secured by "hook and loop" fasteners (such as Velcro) and is only opened at the end of the flight. Balloons equipped with a Velcro-style vent typically have a second "maneuvering vent" built into the side (as opposed to the top) of the balloon. Another common type of top design is the "smart vent", which, rather than lowering a fabric disc into the envelope as in the "parachute" type, gathers the fabric together in the center of the opening. This system can theoretically be used for in-flight maneuvering, but is more commonly used only as a rapid-deflation device for use after landing, of particular value in high winds. Other designs, such as the "pop top" and "MultiVent" systems, have also attempted to address the need for rapid deflation on landing, but the parachute top remains popular as an all-around maneuvering and deflation system.


Shape

Besides special shapes, possibly for marketing purposes, there are several variations on the traditional "inverted tear drop" shape. The simplest, often used by home builders, is a
hemisphere Hemisphere refers to: * A half of a sphere As half of the Earth * A hemisphere of Earth ** Northern Hemisphere ** Southern Hemisphere ** Eastern Hemisphere ** Western Hemisphere ** Land and water hemispheres * A half of the (geocentric) celes ...
on top of a truncated
cone A cone is a three-dimensional geometric shape that tapers smoothly from a flat base (frequently, though not necessarily, circular) to a point called the apex or vertex. A cone is formed by a set of line segments, half-lines, or lines con ...
. More sophisticated designs attempt to minimize the circumferential
stress Stress may refer to: Science and medicine * Stress (biology), an organism's response to a stressor such as an environmental condition * Stress (linguistics), relative emphasis or prominence given to a syllable in a word, or to a word in a phrase ...
on the fabric, with different degrees of success depending on whether they take fabric weight and varying air density into account. This shape may be referred to as "natural". Finally, some specialized balloons are designed to minimize aerodynamic drag (in the vertical direction) to improve flight performance in competitions.


Basket

Hot air balloon baskets are commonly made of
woven Woven fabric is any textile formed by weaving. Woven fabrics are often created on a loom, and made of many threads woven on a warp and a weft. Technically, a woven fabric is any fabric made by interlacing two or more threads at right angles to on ...
wicker or
rattan Rattan, also spelled ratan, is the name for roughly 600 species of Old World climbing palms belonging to subfamily Calamoideae. The greatest diversity of rattan palm species and genera are in the closed- canopy old-growth tropical fores ...
. These materials have proven to be sufficiently light, strong, and durable for balloon flight. Such baskets are usually rectangular or triangular in shape. They vary in size from just big enough for two people to large enough to carry thirty. Larger baskets often have internal partitions for structural bracing and to compartmentalize the passengers. Small holes may be woven into the side of the basket to act as foot holds for passengers climbing in or out. Baskets may also be made of
aluminium Aluminium (aluminum in American and Canadian English) is a chemical element with the symbol Al and atomic number 13. Aluminium has a density lower than those of other common metals, at approximately one third that of steel. I ...
, especially a collapsible aluminium frame with a fabric skin, to reduce weight or increase portability. These may be used by pilots without a ground crew or who are attempting to set altitude, duration, or distance records. Other specialty baskets include the fully enclosed gondolas used for around-the-world attempts and baskets that consist of little more than a seat for the pilot and perhaps one passenger.


Burner

The burner unit gasifies liquid propane, mixes it with air, ignites the mixture, and directs the flame and exhaust into the mouth of the envelope. Burners vary in power output; each will generally produce 2 to 3 MW of heat (7 to 10 million BTUs per hour), with double, triple, or quadruple burner configurations installed where more power is needed. The pilot actuates a burner by opening a propane valve, known as a blast valve. The valve may be spring-loaded, so that it closes automatically, or it may stay open until closed by the pilot. The burner has a
pilot light Merker Tankless water heating, tankless gas-fired water heater from the 1930s, with pilot light clearly visible through the aperture in the front cover. The large opening allowed for the manual lighting of the pilot light by a lit match or taper ...
to ignite the propane and air mixture. The pilot light may be lit by the pilot with an external device, such as a
flint Flint, occasionally flintstone, is a sedimentary cryptocrystalline form of the mineral quartz, categorized as the variety of chert that occurs in chalk or marly limestone. Flint was widely used historically to make stone tools and sta ...
striker or a
lighter A lighter is a portable device which creates a flame, and can be used to ignite a variety of items, such as cigarettes, gas lighter, fireworks, candles or campfires. It consists of a metal or plastic container filled with a flammable liquid or ...
, or with a built-in
piezoelectric Piezoelectricity (, ) is the electric charge that accumulates in certain solid materials—such as crystals, certain ceramics, and biological matter such as bone, DNA, and various proteins—in response to applied mechanical stress. The word '' ...
spark. Where more than one burner is present, the pilot can use one or more at a time, depending on the desired heat output. Each burner has a metal coil of propane tubing the flame shoots through to preheat the incoming liquid propane. The burner unit may be suspended from the mouth of the envelope or supported rigidly over the basket. The burner unit may be mounted on a
gimbal A gimbal is a pivoted support that permits rotation of an object about an axis. A set of three gimbals, one mounted on the other with orthogonal pivot axes, may be used to allow an object mounted on the innermost gimbal to remain independent of ...
to enable the pilot to aim the flame and avoid overheating the envelope fabric. A burner may have a secondary propane valve that releases propane more slowly and thereby generates a different sound. This is called a ''whisper burner'' and is used for flight over livestock to lessen the chance of spooking them. It also generates a more yellow flame and is used for night glows because it lights up the inside of the envelope better than the primary valve.


Fuel tanks

Propane fuel tanks are usually cylindrical pressure vessels made from
aluminium Aluminium (aluminum in American and Canadian English) is a chemical element with the symbol Al and atomic number 13. Aluminium has a density lower than those of other common metals, at approximately one third that of steel. I ...
, stainless steel, or
titanium Titanium is a chemical element with the Symbol (chemistry), symbol Ti and atomic number 22. Found in nature only as an oxide, it can be reduced to produce a lustrous transition metal with a silver color, low density, and high strength, resista ...
with a valve at one end to feed the burner and to refuel. They may have a
fuel gauge In automotive and aerospace engineering, a fuel gauge is an instrument used to indicate the amount of fuel in a fuel tank. In electrical engineering, the term is used for ICs determining the current State of Charge of accumulators. Motor vehi ...
and a
pressure gauge Pressure measurement is the measurement of an applied force by a fluid ( liquid or gas) on a surface. Pressure is typically measured in units of force per unit of surface area. Many techniques have been developed for the measurement of pres ...
. Common tank sizes are . They may be intended for upright or horizontal use and may be mounted inside or outside the basket. The pressure necessary to force the fuel through the line to the burner may be supplied by the
vapor pressure Vapor pressure (or vapour pressure in English-speaking countries other than the US; see spelling differences) or equilibrium vapor pressure is defined as the pressure exerted by a vapor in thermodynamic equilibrium with its condensed phas ...
of the propane itself, if warm enough, or by the introduction of an inert gas such as
nitrogen Nitrogen is the chemical element with the symbol N and atomic number 7. Nitrogen is a nonmetal and the lightest member of group 15 of the periodic table, often called the pnictogens. It is a common element in the universe, estimated at se ...
. Tanks may be preheated with electrical heat tapes to produce sufficient vapor pressure for cold-weather flying. Warmed tanks are usually also wrapped in an insulating blanket to preserve heat during the setup and flight.


Instrumentation

A balloon may be outfitted with a variety of instruments to aid the pilot. These commonly include an
altimeter An altimeter or an altitude meter is an instrument used to measure the altitude of an object above a fixed level. The measurement of altitude is called altimetry, which is related to the term bathymetry, the measurement of depth under water. The m ...
, a rate-of-climb (vertical-speed) indicator known as a
variometer In aviation, a variometer – also known as a rate of climb and descent indicator (RCDI), rate-of-climb indicator, vertical speed indicator (VSI), or vertical velocity indicator (VVI) – is one of the flight instruments in an aircraft used to i ...
, envelope (air) temperature, and ambient (air) temperature. A
GPS The Global Positioning System (GPS), originally Navstar GPS, is a satellite-based radionavigation system owned by the United States government and operated by the United States Space Force. It is one of the global navigation satellite sy ...
receiver can be useful to indicate ground speed (traditional aircraft air-speed indicators would be useless) and direction.


Combined mass

The combined mass of an average system can be calculated as follows: : :: * Using a
density Density (volumetric mass density or specific mass) is the substance's mass per unit of volume. The symbol most often used for density is ''ρ'' (the lower case Greek letter rho), although the Latin letter ''D'' can also be used. Mathematical ...
of for dry air heated to .


Theory of operation


Generating lift

Increasing the air temperature inside the envelope makes it less dense than the surrounding (ambient) air. The balloon floats because of the buoyant force exerted on it. This force is the same force that acts on objects when they are in water and is described by
Archimedes' principle Archimedes' principle (also spelled Archimedes's principle) states that the upward buoyant force that is exerted on a body immersed in a fluid, whether fully or partially, is equal to the weight of the fluid that the body displaces. Archimedes' ...
. The amount of lift (or
buoyancy Buoyancy (), or upthrust, is an upward force exerted by a fluid that opposes the weight of a partially or fully immersed object. In a column of fluid, pressure increases with depth as a result of the weight of the overlying fluid. Thus the ...
) provided by a hot air balloon depends primarily upon the difference between the temperature of the air inside the envelope and the temperature of the air outside the envelope. For most envelopes made of nylon fabric, the maximal internal temperature is limited to approximately 120 °C (250 °F). The melting point of nylon is significantly greater than this maximal operating temperature — about 230 °C (450 °F) — but higher temperatures cause the strength of the nylon fabric to degrade more quickly over time. With a maximal operating temperature of 120 °C (250 °F), balloon envelopes can generally be flown for between 400 and 500 hours before the fabric needs to be replaced. Many balloon pilots operate their envelopes at temperatures significantly less than the maximum to extend envelope-fabric life. The lift generated by of dry air heated to various temperatures may be calculated as follows: : The
density of air The density of air or atmospheric density, denoted '' ρ'', is the mass per unit volume of Earth's atmosphere. Air density, like air pressure, decreases with increasing altitude. It also changes with variation in atmospheric pressure, temperature a ...
at is about . The total lift for a balloon of heated to would be . This is just enough to generate neutral buoyancy for the total system mass (not including the heated air trapped in the envelope, of course) stated in the previous section. Liftoff would require a slightly greater temperature, depending on the desired rate of climb. In reality, the air contained in the envelope is not all at the same temperature, as the accompanying thermal image shows, and so these calculations are based on averages. For typical atmospheric conditions (), a hot air balloon heated to requires about 3.91 m3 of envelope volume to lift 1 kilogram (equivalently, 62.5 cu ft/lb). The precise amount of lift provided depends not only upon the internal temperature mentioned above, but the external temperature, altitude above sea level, and humidity of the air surrounding. On a warm day, a balloon cannot lift as much as on a cool day, because the temperature required for launch will exceed the maximum sustainable for nylon envelope fabric. Also, in the lower atmosphere, the lift provided by a hot air balloon decreases about 3% per 1,000 m (1% per 1,000 ft) of altitude gained.


Montgolfier

Standard hot air balloons are known as Montgolfier balloons and rely solely on the buoyancy of hot air provided by the burner and contained by the envelope. This style of balloon was developed by the
Montgolfier brothers The Montgolfier brothers – Joseph-Michel Montgolfier (; 26 August 1740 – 26 June 1810) and Jacques-Étienne Montgolfier (; 6 January 1745 – 2 August 1799) – were aviation pioneers, balloonists and paper manufacturers from the commune A ...
and had its first public demonstration on 4 June 1783 with an unmanned flight lasting 10 minutes, followed later that year with manned flights.


Hybrid

The 1785
Rozière balloon A Rozière balloon (or simply Rozière) is a type of hybrid balloon that has separate chambers for a non-heated lifting gas (such as hydrogen or helium) as well as for a heated lifting gas (as used in a hot air balloon or Montgolfière). The design ...
, a type of hybrid balloon, named after its creator, Jean-François Pilâtre de Rozier, has a separate cell for a lighter-than-air gas (typically
helium Helium (from el, ἥλιος, helios, lit=sun) is a chemical element with the symbol He and atomic number 2. It is a colorless, odorless, tasteless, non-toxic, inert, monatomic gas and the first in the noble gas group in the periodic table. ...
), as well as a cone below for hot air (as is used in a hot air balloon) to heat the helium at night.
Hydrogen Hydrogen is the chemical element with the symbol H and atomic number 1. Hydrogen is the lightest element. At standard conditions hydrogen is a gas of diatomic molecules having the formula . It is colorless, odorless, tasteless, non-toxic ...
gas was used in the very early stages of development, but was quickly abandoned due to the danger of introducing an open flame near the gas. All modern Roziere balloons now use helium as a
lifting gas A lifting gas or lighter-than-air gas is a gas that has a density lower than normal atmospheric gases and rises above them as a result. It is required for aerostats to create buoyancy, particularly in lighter-than-air aircraft, which include ballo ...
.


Solar

Solar balloon A solar balloon is a balloon that gains buoyancy when the air inside is heated by solar radiation, usually with the help of black or dark balloon material. The heated air inside the solar balloon expands and has lower density than the surrounding ...
s are hot air balloons that use just solar energy captured by a dark envelope to heat the air inside.


Steering

Hot air balloon can be steered to a limited degree by changing the altitude of the flight. Wind in the northern hemisphere tends to turn east due to
coriolis effect In physics, the Coriolis force is an inertial or fictitious force that acts on objects in motion within a frame of reference that rotates with respect to an inertial frame. In a reference frame with clockwise rotation, the force acts to the ...
as the altitude increases.


Safety equipment

To help ensure the safety of pilot and passengers, a hot air balloon may carry several pieces of safety equipment.


In the basket

To relight the burner if the pilot light goes out and the optional piezo ignition fails, the pilot should have ready access to a means of backup ignition, such as a flint spark lighter. Many systems, especially those that carry passengers, have completely duplicate fuel and burner systems: two fuel tanks, connected to two separate hoses, which feed two distinct burners. This enables a safe landing in the case of a blockage somewhere in one system or if a system must be disabled because of a fuel leak. A
fire extinguisher A fire extinguisher is a handheld active fire protection device usually filled with a dry or wet chemical used to extinguish or control small fires, often in emergencies. It is not intended for use on an out-of-control fire, such as one which ha ...
suitable for extinguishing propane fires is useful. Most balloons carry a 1 or 2 kg AB:E type fire extinguisher. A handling or drop line is mandatory safety equipment in many countries. This is a rope or webbing of 20–30 meters in length attached to the balloon basket with a quick-release connection at one end. In very calm winds the balloon pilot can throw the handling line from the balloon so that the ground crew can guide the balloon safely away from obstructions on the ground. For commercial passenger balloons, a pilot restraint harness is mandatory in some countries. This consists of a hip belt and a webbing line that together allow for some movement while preventing the pilot from being ejected from the basket during a hard landing. Further safety equipment may include a first-aid kit, a fire blanket and a strong rescue knife.


On the occupants

At a minimum, the pilot should wear leather or flame-retardant fiber (such as
nomex Nomex is a flame-resistant meta-aramid material developed in the early 1960s by DuPont and first marketed in 1967. Properties Nomex and related aramid polymers are related to nylon, but have aromatic backbones, and hence are more rigid and mo ...
) gloves, so that they may shut off a gas valve in the case of a leak, even if there is a flame present; quick action in this regard can turn a potential catastrophe into a mere inconvenience. The pilot should additionally wear flame-resistant clothing covering their arms and legs; either natural fiber, such as
cotton Cotton is a soft, fluffy staple fiber that grows in a boll, or protective case, around the seeds of the cotton plants of the genus '' Gossypium'' in the mallow family Malvaceae. The fiber is almost pure cellulose, and can contain minor pe ...
, linen, hemp, or
wool Wool is the textile fibre obtained from sheep and other mammals, especially goats, rabbits, and camelids. The term may also refer to inorganic materials, such as mineral wool and glass wool, that have properties similar to animal wool. ...
, or engineered flame-retardant fiber, such as nomex, is acceptable in this capacity. Most engineered fibers (with the exception of rayon, which is also safe to wear) are
thermoplastic A thermoplastic, or thermosoft plastic, is any plastic polymer material that becomes pliable or moldable at a certain elevated temperature and solidifies upon cooling. Most thermoplastics have a high molecular weight. The polymer chains associate ...
; many are also
hydrocarbons In organic chemistry, a hydrocarbon is an organic compound consisting entirely of hydrogen and carbon. Hydrocarbons are examples of group 14 hydrides. Hydrocarbons are generally colourless and hydrophobic, and their odors are usually weak or e ...
. This makes such fabrics very much unsuitable to wear near high temperatures, since non-flame-retardant thermoplastics will melt onto the wearer, and most hydrocarbons, whether fibrous or not, are suitable to use as fuels. Natural fiber will singe rather than melt or burn readily, and flame-retardant fiber generally has a very high melting point and is intrinsically non-flammable. Many pilots also advise their passengers to wear similar protective clothing that covers their arms and legs, as well as strong shoes or boots that offer good ankle support. Finally, some balloon systems, especially those that hang the burner from the envelope instead of supporting it rigidly from the basket, require the use of helmets by the pilot and passengers.


On the ground crew

The ground crew should wear gloves whenever there is a possibility of handling ropes or lines. The mass and exposed surface to air movement of a medium-sized balloon is sufficient to cause rope friction burns to the hands of anyone trying to stop or prevent movement. The ground crew should also wear sturdy shoes and at least long pants in case of the need to access a landing or landed balloon in rough or overgrown terrain.


Maintenance and repair

As with aircraft, hot air balloons require regular maintenance to remain airworthy. As aircraft made of fabric and that lack direct horizontal control, hot air balloons may occasionally require repairs to rips or snags. While some operations, such as cleaning and drying, may be performed by the owner or pilot, other operations, such as sewing, must be performed by a qualified repair technician and recorded in the balloon's maintenance log book.


Maintenance

To ensure long life and safe operation, the envelope should be kept clean and dry. This prevents
mold A mold () or mould () is one of the structures certain fungi can form. The dust-like, colored appearance of molds is due to the formation of spores containing fungal secondary metabolites. The spores are the dispersal units of the fungi. Not ...
and mildew from forming on the fabric and abrasion from occurring during packing, transport, and unpacking due to contact with foreign particles. In the event of a landing in a wet (because of precipitation or early morning or late evening dew) or muddy location (farmer's field), the envelope should be cleaned and laid out or hung to dry. The burner and fuel system must also be kept clean to ensure safe operation on demand. Damaged fuel hoses need to be replaced. Stuck or leaky valves must be repaired or replaced. The wicker basket may require occasional refinishing or repair. The skids on its bottom may require occasional replacement. Balloons in most parts of the world are maintained in accordance with a fixed manufacturer's maintenance schedule that includes regular (100 flight hours or 12 month) inspections, in addition to maintenance work to correct any damage. In Australia, balloons used for carrying commercial passengers must be inspected and maintained by approved workshops.


Repair

In the case of a snag, burn, or rip in the envelope fabric, a patch may be applied or the affected panel completely replaced. Patches may be held in place with glue, tape, stitching, or a combination of these techniques. Replacing an entire panel requires the stitching around the old panel to be removed, and a new panel to be sewn in with the appropriate technique, thread, and stitch pattern.


Licensing

Depending on the size of the balloon, location, and intended use, hot air balloons and their pilots need to comply with a variety of regulations.


Balloons

As with other aircraft in the US, balloons must be registered (have an
N-number An aircraft registration is a code unique to a single aircraft, required by international convention to be marked on the exterior of every civil aircraft. The registration indicates the aircraft's country of registration, and functions much lik ...
), have an
airworthiness In aviation, airworthiness is the measure of an aircraft's suitability for safe flight. Initial airworthiness is demonstrated by a certificate of airworthiness issued by the civil aviation authority in the state in which the aircraft is register ...
certificate, and pass annual inspections. Balloons below a certain size (empty weight of less than 155 pounds or 70 kg including envelope, basket, burners and empty fuel tanks) can be used as an ultralight aircraft.


Pilots


In Australia

In Australia, private balloon pilots are managed by the Australian Ballooning Federation and typically become members of regional hot air ballooning clubs. Commercial operations carrying fare paying passengers or charging for promotional flights must operate under an Air Operators Certificate from the Australian Civil Aviation and Safety Authority (CASA) with a nominated Chief Pilot. Pilots must have different degrees of experience before they are allowed to progress to larger balloons. Hot air balloons must be registered aircraft with CASA and are subject to regular airworthiness checks by authorised personnel.


In the UK

In the UK, the person in command must hold a valid Private Pilot's Licence issued by the Civil Aviation Authority specifically for ballooning; this is known as the PPL(B). There are two types of commercial balloon licences: CPL(B) Restricted and CPL(B) (Full). The CPL(B) Restricted is required if the pilot is undertaking work for a sponsor or being paid by an external agent to operate a balloon. The pilot can fly a sponsored balloon with everything paid for with a PPL unless asked to attend any event. Then a CPL(B) Restricted is required. The CPL(B) is required if the pilot is flying passengers for money. The balloon then needs a transport category C of A (certificate of air worthiness). If the pilot is only flying sponsor's guests and not charging money for flying other passengers, then the pilot is exempted from holding an AOC (air operator's certificate) though a copy of it is required. For passenger flying the balloon also requires a maintenance log.


In the United States

In the United States, a pilot of a hot air balloon must have a pilot certificate from the
Federal Aviation Administration The Federal Aviation Administration (FAA) is the largest transportation agency of the U.S. government and regulates all aspects of civil aviation in the country as well as over surrounding international waters. Its powers include air traffic ...
(FAA), carrying the rating of "Lighter-than-air free balloon", and unless the pilot is also qualified to fly gas balloons, will also carry this limitation: "Limited to hot-air balloons with airborne heater". A pilot does not need a license to fly an
ultralight Ultralight aviation (called microlight aviation in some countries) is the flying of lightweight, 1- or 2-seat fixed-wing aircraft. Some countries differentiate between weight-shift control and conventional three-axis control aircraft with aile ...
aircraft, but training is highly advised, and some hot-air balloons meet the criteria. To carry paying passengers for hire (and attend some balloon festivals), a pilot must have a commercial pilot certificate. Commercial hot air balloon pilots may also act as hot air balloon
flight instructor A flight instructor is a person who teaches others to operate aircraft. Specific privileges granted to holders of a flight instructor qualification vary from country to country, but very generally, a flight instructor serves to enhance or evaluate ...
s. While most balloon pilots fly for the pure joy of floating through the air, many are able to make a living as a professional balloon pilot. Some professional pilots fly commercial passenger sightseeing flights, while others fly corporate advertising balloons.


Accidents and incidents

* 1989 Alice Springs hot air balloon crash: On 13 August 1989, two hot air balloons collided at
Alice Springs, Northern Territory Alice Springs ( aer, Mparntwe) is the third-largest town in the Northern Territory of Australia. Known as Stuart until 31 August 1933, the name Alice Springs was given by surveyor William Whitfield Mills after Alice, Lady Todd (''née'' Ali ...
, Australia, causing one to fall, killing all 13 people on board. * 2011 Somerset hot air balloon crash: On 1 January 2011, a hot air balloon attempting a high-altitude flight crashed at Pratten's Bowls Club in
Westfield, Somerset Westfield is a settlement lying on the Fosse Way between Radstock and Midsomer Norton in Somerset, England. In 2011 it was raised to the status of a civil parish. It is south-west of Bath, north-east of Wells, west of Trowbridge, north-wes ...
, near Bath, England, killing both people on board. *
2012 Carterton hot air balloon crash On 7 January 2012, a scenic hot air balloon flight from Carterton, New Zealand, collided with a high-voltage power line while attempting to land, causing it to catch fire, disintegrate and crash just north of the town, killing all eleven people ...
: On 7 January 2012, a hot air balloon collided with a power line, caught fire and crashed at
Carterton, North Island Carterton ( mi, Taratahi) is a small town in the Wellington Region of New Zealand and the seat of the Carterton District (a territorial authority or local government district). It lies in a farming area of the Wairarapa in New Zealand's North Isl ...
, New Zealand, killing all 11 people on board. *
2012 Ljubljana Marshes hot air balloon crash On 23 August 2012, a hot air balloon on a commercial sightseeing flight crashed in stormy weather on the Ljubljana Marsh in central Slovenia, killing 6 of the 32 people on board. Accident upright=0.9, The storm front at the time of the crash, ...
: On 23 August 2012, a storm blew a hot air balloon to the ground, causing it to catch fire on impact near
Ljubljana Ljubljana (also known by other historical names) is the capital and largest city of Slovenia. It is the country's cultural, educational, economic, political and administrative center. During antiquity, a Roman city called Emona stood in the are ...
, Slovenia. The crash killed 6 of the 32 people on board, and injured the other 26. * 2013 Luxor hot air balloon crash: On 26 February 2013, a hot air balloon carrying foreign tourists ignited and crashed near the ancient city of
Luxor Luxor ( ar, الأقصر, al-ʾuqṣur, lit=the palaces) is a modern city in Upper (southern) Egypt which includes the site of the Ancient Egyptian city of ''Thebes''. Luxor has frequently been characterized as the "world's greatest open-a ...
, Egypt, killing 19 of the 21 people on board, making it the deadliest balloon accident in history. *
2016 Lockhart hot air balloon crash On July 30, 2016, sixteen people were killed when the hot air balloon they were riding in struck power lines, crashed and caught fire in the unincorporated community of Maxwell, near Lockhart, Texas, south of the state capital Austin. It is th ...
: On 30 July 2016, a hot air balloon carrying 16 people caught fire and crashed near
Lockhart, Texas Lockhart is a city and the county seat of Caldwell County, Texas, United States. According to the 2020 census, its population was 14,379. History The city of Lockhart is named after Byrd Lockhart, an assistant surveyor of Green DeWitt and rep ...
. There were no survivors. * 2021 Albuquerque hot air balloon crash: On 26 June 2021, a hot air balloon carrying five people made contact with a power line and crashed in Albuquerque, New Mexico. All five people on board died as a result of the accident.


Manufacturers

The largest manufacturer of hot air balloons is Cameron Balloons of
Bristol Bristol () is a city, ceremonial county and unitary authority in England. Situated on the River Avon, it is bordered by the ceremonial counties of Gloucestershire to the north and Somerset to the south. Bristol is the most populous city in ...
, England, which also owns Lindstrand Balloons of Oswestry, England. Cameron Balloons, Lindstrand Balloons and another English balloon manufacturing company Thunder and Colt (since acquired by Cameron) have been innovators and developers of special shaped balloons. These hot-air balloons use the same principle of lift as conventional inverted teardrop-shaped balloons, but often sections of the special balloon envelope shape do not contribute to the balloon's ability to stay aloft. The second largest manufacturer of hot air balloons is Ultramagic company, based in Spain, which produces from 80 to 120 balloons per year. Ultramagic can produce very large balloons, such as the N-500 that accommodates as many as 27 persons in the basket, and has also produced many balloons with special shapes, as well as cold-air inflatables. One of the three largest companies in the world is Kubicek Balloons. From its factory in Brno,
Czechia The Czech Republic, or simply Czechia, is a landlocked country in Central Europe. Historically known as Bohemia, it is bordered by Austria to the south, Germany to the west, Poland to the northeast, and Slovakia to the southeast. The Cz ...
the company ships its products worldwide. Produces from 100 to 115 balloons per year. Kubicek company also focus on special shape balloons, FAA/EASA type certified and are delivered with a Standard Airworthiness Certificate. In the USA Aerostar International, Inc. of
Sioux Falls, South Dakota Sioux Falls () is the most populous city in the U.S. state of South Dakota and the 130th-most populous city in the United States. It is the county seat of Minnehaha County and also extends into Lincoln County to the south, which continues up ...
was North America's largest balloon manufacturer and a close second in world manufacturing before ceasing to build balloons in January 2007. The oldest U.S. certified manufacturer is now Adams Balloons out of Albuquerque, New Mexico. Firefly Balloons, formerly The Balloon Works, is a manufacturer of hot air balloons in
Statesville, North Carolina Statesville is a city in and the county seat of Iredell County, North Carolina, United States, and it is part of the Charlotte metropolitan area. Statesville was established in 1789 by an act of the North Carolina Legislature. The population was r ...
. Another manufacturer is Head Balloons, Inc. of
Helen, Georgia Helen is a city in White County, Georgia, United States, located along the Chattahoochee River. The population was 531 at the 2020 census. History Helen was platted in 1912, and named after the daughter of a lumber official. The town was incorp ...
. The major manufacturers in Canada are
Sundance Balloons A Sun Dance is a Native American ceremony. Sun dance or Sundance may also refer to: Places ;Canada * Sundance, Calgary, Alberta, a neighbourhood * Sundance, Manitoba, a ghost town ;United States * Sundance, New Mexico, a census-designated pla ...
and Fantasy Sky Promotions. Other manufacturers include Kavanagh Balloons of Australia, Schroeder Fire Balloons of Germany, Kubicek Balloons of the Czech Republic, and LLopis Balloons of France.


See also

* Barrage balloon *
Blimp A blimp, or non-rigid airship, is an airship (dirigible) without an internal structural framework or a keel. Unlike semi-rigid and rigid airships (e.g. Zeppelins), blimps rely on the pressure of the lifting gas (usually helium, rather than hy ...
*
Cinebulle The Cinebulle is a hot air balloon specially adapted for filming.Cluster ballooning Cluster ballooning is a form of ballooning where a harness attaches a balloonist to a cluster of helium-inflated rubber balloons. Unlike traditional hot-air balloons, where a single large balloon is equipped with vents enabling altitude control ...
*
Espionage balloon Espionage, spying, or intelligence gathering is the act of obtaining secret or confidential information (intelligence) from non-disclosed sources or divulging of the same without the permission of the holder of the information for a tangib ...
*
Gas balloon A gas balloon is a balloon that rises and floats in the air because it is filled with a gas lighter than air (such as helium or hydrogen). When not in flight, it is tethered to prevent it from flying away and is sealed at the bottom to prevent t ...
*
High-altitude balloon High-altitude balloons are crewed or uncrewed balloons, usually filled with helium or hydrogen, that are released into the stratosphere, generally attaining between above sea level. In 2002, a balloon named BU60-1 reached a record altitude of . ...
* History of military ballooning *
Hot air balloon festival Hot air balloon festivals are held annually in many places throughout the year, allowing hot air balloons operators to gather- as well as for the general public- to participate in various activities. They can include races; evening "night glows" ...
* Hot air ballooning * Observation balloon * Research balloon *
Skyhook balloon Skyhook balloons were high-altitude balloons developed by Otto C. Winzen and General Mills, Inc. They were used by the United States Navy Office of Naval Research (ONR) in the late 1940s and 1950s for atmospheric research, especially for const ...


References

* Needham, Joseph (1986).'' Science and Civilization in China: Volume 4, Physics and Physical Technology, Part 2, Mechanical Engineering''. Taipei: Caves Books Ltd.


External links


General ballooning sites


Hot Air Ballooning – How balloons fly, list of balloon clubs, free classified ads for balloonists


{{DEFAULTSORT:Hot Air Balloon Balloons (aeronautics) Airship technology Symbols of New Mexico French inventions 18th-century inventions ang:Ballōn (lyftcræft)#Hātlyftballōn