Wednesday, September 16, 2020 – Hot Air Balloons
- Mary Reed
- Sep 17, 2020
- 13 min read
I walk by a house I have passed many times before, and it still has the same hot air balloon decal in a front window. Whoever lives here either really loves hot air balloons or is too lazy to replace the decal with something new. I have never ridden in a hot air balloon. However, Longview — an East Texas town where I lived for 30 years — had an annual hot air balloon festival. There was an early morning hot air balloon key grab where hoisted high on a pole were the keys to a new car. Whichever hot air balloon that could first reach out and grab the keys won the new car. It was a very popular contest. There was also a balloon glow at dusk where several hot air balloons gathered in a field and simply lit their burners. It was a beautiful sight to see all the multicolor balloons illuminated with firelight in the near darkness. You could even volunteer to be part of the hot air balloon chase team. Requirements were to rise at the crack of dawn and follow the balloon in your car. Sometimes you got to unfold the balloon and watch it inflate before takeoff or fold up the balloon itself after landing and deflating.
According to Wikipedia, a hot air balloon is a lighter-than-air aircraft consisting of a bag, called an envelope, which contains heated air. Suspended beneath is a gondola or wicker basket (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 since it has a lower density than the colder air outside the envelope. As with all aircraft, 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 fabric, and the inlet of the balloon (closest to the burner flame) is made from a fire resistant material such as Nomex. Modern balloons have been made in all kinds of shapes — such as rocket ships and the shapes of various commercial products — though the traditional shape is used for most noncommercial and many commercial applications.
The hot air balloon is the first successful human-carrying flight technology. The first untethered manned hot air balloon flight was performed by Jean-François Pilâtre de Rozier and François Laurent d’Arlandes on November 21, 1783, in Paris, France, in a balloon created by the Montgolfier brothers. 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. Hot air balloons that can be propelled through the air rather than simply drifting with the wind are known as thermal airships.
Premodern and unmanned balloons
Unmanned hot air balloons are popular in Chinese history. Chuge Liang of the Shu Han kingdom, in the Three Kingdoms era (c. AD 220–280) used airborne lanterns for military signaling. These lanterns are known as Kongming lanterns.
The first documented balloon flight in Europe was by the Brazilian-Portuguese priest Bartolomeu de Gusmão. On August 8, 1709, in Lisbon, Bartolomeu de Gusmão managed to lift a small balloon made of paper full of hot air about four meters in front of king John V and the Portuguese court.
First hydrogen balloon
Following Robert Boyle’s “Boyle’s Law” which had been published in 1662, and Henry Cavendish's 1766 work on hydrogen, Joseph Black proposed that if the gaseous element filled a balloon, the inflated object could rise up into the air. Jacques Charles, whose study of gases led to his namesake law of volumes, had studied the works of Cavendish, Black and Tiberius Cavallo, and also thought that hydrogen could lift a balloon.
Jacques Charles designed the balloon, and the Robert brothers constructed a lightweight, airtight gas bag. Barthélémy Faujas de Saint-Fond organized a crowd-funded subscription to finance the brothers' project. The Roberts dissolved rubber in a solution of turpentine, with which they varnished stitched-together sheets of silk, to make the main envelope. They used alternating strips of red and white silk, but the rubberizing varnish yellowed the white silk.
Jacques Charles and the Robert brothers began filling the world's first hydrogen baloon on August 23, 1783, in the Place des Victoires, Paris. The balloon was comparatively small, a 35-cubic-metre sphere of rubberized silk (about 13 feet in diameter), and only capable of lifting about 9 kg. It was filled with hydrogen that had been made by pouring nearly a quarter of a ton of sulphuric acid onto half a ton of scrap iron. The hydrogen gas was fed into the envelope via lead pipes; as it was not passed through cold water, the gas was hot when produced, and then contracted as it cooled in the balloon, causing great difficulty in filling the balloon completely. Daily progress bulletins were issued on the inflation, attracting a crowd that became so great that on the 26th the balloon was moved secretly by night to the Champ de Mars (now the site of the Eiffel Tower), a distance of 4 kilometers. On August 27, 1783, the balloon was released; Benjamin Franklin was among the crowd of onlookers.
The balloon flew northwards for 45 minutes, pursued by chasers on horseback, and landed 21 kilometers away in the village of Gonesse, where the reportedly terrified local peasants attacked it with pitchforks and knives and destroyed it.
First unmanned flight
On June 5, 1783, the Montgolfier brothers first publicly demonstrated an unmanned hot-air balloon 35 feet in diameter. On September 19, 1783, their balloon Aerostat Réveillon was flown with the first (non-human) living creatures in a basket attached to the balloon: a sheep called Montauciel ("Climb-to-the-sky"), a duck and a rooster. The sheep was believed to have a reasonable approximation of human physiology. The duck was expected to be unharmed by being lifted aloft. It was included as a control for effects created by the aircraft rather than the altitude. The rooster was included as a further control as it was a bird that did not fly at high altitudes. This demonstration was performed before a crowd at the royal palace in Versailles, before King Louis XVI of France and Queen Marie Antointte. The flight lasted approximately eight minutes, covered two miles and obtained an altitude of about 1,500 feet. The craft landed safely after flying.
First manned flight
The first clearly recorded instance of a balloon carrying human passengers used hot air to generate buoyancy and was built by the brothers Joseph-Michel and Jacques-Etienne Montgolfier in Annonay, France. These brothers came from a family of paper manufacturers and had noticed ash rising in paper fires. The Montgolfier brothers gave their first public demonstration of their invention on June 4, 1783. After experimenting with unmanned balloons and flights with animals, the first tethered balloon flight with humans on board took place on October 19, 1783, with the scientist Jean-François Pilâtre de Rozier, the manufacture manager Jean-Baptiste Réveillon and Giroud de Villette, at the Folie Titon in Paris.
The first untethered, free flight with human passengers was on November 21, 1783. King Louis XVI had originally decreed that condemned criminals would be the first pilots, but de Rozier, along with the Marquis François d’Arlandes, successfully petitioned for the honor. For this occasion the diameter of the balloon rose to almost 50 feet, with a smoky fire slung under the neck of the balloon placed in an iron basket; it was controllable and replenishable by the balloonists. In 25 minutes the two men traveled just over five miles. Enough fuel remained on board at the end of the flight to have allowed the balloon to fly four to five times as far, but burning embers from the fire threatened to engulf the balloon and the men decided to land as soon as they were over open countryside.
News of the balloon flights spread quickly. By December 1783 Goethe wrote to a friend on Wilheim Heinrich Sebastian Bucholz's attempt in Weimar "to master the art of Montgolfier. "The pioneering work of the Montgolfier brothers in developing the hot air balloon was recognized by this type of balloon being named Montgolfière after them.
First manned hydrogen balloon flight
Only a few days later, at 13:45 on December 1, 1783, professor Jacques Charles and the Robert brothers launched a new, manned hydrogen balloon from the Jardin des Tuileries in Paris, amid vast crowds and excitement. The balloon was held on ropes and led to its final launch place by four of the leading noblemen in France, the Marechal de Richelieu, Marshal de Biron, the Bailli de Suffren and the Duke of Chaulnes. Jacques Charles was accompanied by Nicolas-Louis Robert as co-pilot of the 380-cubic-meter, hydrogen-filled balloon. The envelope was fitted with a hydrogen release valve, and was covered with a net from which the basket was suspended. Sand ballast was used to control altitude. They ascended to a height of about 1,800 feet and landed at sunset in Nesles-la-Vallée after a flight of 2 hours and 5 minutes, covering 36 km. The chasers on horseback, who were led by the Duc de Chartres, held down the craft while both Charles and Robert alighted.
Charles then decided to ascend again, but alone this time because the balloon had lost some of its hydrogen. This time he ascended rapidly to an altitude of about 3,000 meters, where he saw the sun again. He began suffering from aching pain in his ears so he “valved” to release gas and descended to land gently about 3 km away at Tour du Lay. Unlike the Robert brothers, Charles never flew again, although a balloon using hydrogen for its lift came to be called a Charlière in his honor.
Charles and Robert carried a barometer and a thermometer to measure the pressure and the temperature of the air, making this not only the first manned hydrogen balloon flight, but also the first balloon flight to provide meteorological measurements of the atmosphere above the Earth's surface.
It is reported that 400,000 spectators witnessed the launch, and that hundreds had paid one crown each to help finance the construction and receive access to a "special enclosure" for a "close-up view" of the take-off. Among the "special enclosure" crowd was Benjamin Franklin, the diplomatic representative of the United States of America. Also present was Joseph Montgolfier, whom Charles honored by asking him to release the small, bright green, pilot balloon to assess the wind and weather conditions.
Further milestones
The next great challenge was to fly across the English Channel, a feat accomplished on January 7, 1785 by Jean-Pierre Blanchard.
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 10, 1793. His hydrogen-filled balloon took off from a prison yard in Philadelphia, Pennsyvania. The flight reached 5,800 feet 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.
Balloonists sought a means to control the balloon's direction. 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.
Modern balloons
Modern hot air balloons, with an onboard heat source, were developed by Ed Yost, beginning during the 1950s; his work resulted in his first successful flight, on October 22, 1960. Yost is referred to as the "Father of the Modern Day Hot-Air Balloon." He worked for a high-altitude research division of General Mills in the early 1950s when he left to establish Raven Industries in 1956, along with several colleagues from General Mills. The first modern hot air balloon to be made in the United Kingdom 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 68,986 feet. He took off from downtown Mumbai, India, and landed 150 miles south in Panchale. The previous record of 64,997 feet had been set by Per Lindstrand on June 6, 1988, in Plano, Texas.
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 4,767.10 miles from Japan to Northern Canada. With a volume of 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 recorded the fastest ground speed for a manned balloon at 245 mph.
The longest duration record was set by Swiss psychiatrist Bertrand Piccard, August 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 300 miles south of Cairo. The two men exceeded distance, endurance and time records, traveling 19 days, 21 hours and 55 minutes.
On July 3, 2002, Steve Fossett became the first person to fly around the world alone, nonstop, in any kind of aircraft, by hot air balloon. He launched the balloon Spirit of Freedom from Northam, Western Australia, on June 19, 2002, and returned to Australia on July 3, 2002, subsequently landing in Queensland. Duration and distance of this solo balloon flight was 13 days, 8 hours, 33 minutes (14 days, 19 hours, 50 minutes to landing), 20,626.48 statute miles. The trip set a number of records for ballooning: Fastest (200 miles per hour), breaking his own previous record of 166 miles per hour, Fastest Around the World (13.5 days), Longest Distance Flown Solo in a Balloon (20,482.26 miles) and 24-Hour Balloon Distance (3,186.80 miles on July 1).
Fyodor Konyukhov flew solo round the world on his first attempt in a hybrid hot-air/helium balloon from July 11-23, 2016 for a round-the world time of 268 hours, 20 minutes.
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.
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 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 to ignite the propane and air mixture. The pilot light may be lit by the pilot with an external device, such as a flint striker or a lighter, or with a built-in piezo electric 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 is characterized by 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 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.
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 on top of a truncated cone. More-sophisticated designs attempt to minimize the circumferential stress 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.
Albuquerque International Balloon Fiesta
The Albuquerque International Balloon Fiesta is a yearly hot air balloon festival that takes place in Albuquerque, New Mexico, during early October. The Balloon Fiesta is a nine-day event occurring in the first full week of October and has over 500 hot air balloons each year — far from its humble beginnings of merely 13 balloons in 1972. The event is the largest balloon festival in the world, followed by the Grand Est Mondial Air in France.
The number of registered balloons reached a peak of 1,019 in 2000, prompting the Balloon Fiesta Board to limit the number to 750 starting in 2001, citing a desire for "quality over quantity." The limit was changed to 600 in 2009, citing recent growth in the city and a loss of landing zones. It has increased to 1,000 in 2011. On any given day during the festival, up to 100,000 spectators may be on the launch field where they are provided the rare opportunity to observe inflation and take off procedures. Countless more people gather at landing sites all over the city to watch incoming balloons.
Many non-traditional, uniquely shaped balloons are launched at the same time at the Special Shape Rodeo. Some of the most famous shapes include a milk cow, a wagon coach, twin bees and many others like soda pop cans and animals. This is the most popular part of the event as families can see how balloons can be all different in shapes and sizes.
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