This is the correct name that represents the class of aircraft that hover in the sky NOT through the wings, but thanks to the boost provided by a mass of lighter than air gas.
Depending on which gas they use, we can distinguish them: Helium balloons (the gas now used more as it is not flammable), type Rozier balloons (hybrid of hot-air balloons and helium), hot-air balloons (the classic hot air balloons).
According to legends, the first balloons were invented in Peru.
The story is confused about this, but it is thought to have served to draw the famous Nasca Lines and drawings depicting primitive flying objects were found on many of the pottery remains found in the area.
Close to some of these designs they were also found holes and dark circles that are supposed -but not tried- they were bases for the fires from which to take off balloons.
According to a local signs in the desert were made by Viracochas divinity, worshiped by the Incas, who described them as beings with a beard and with white skin, with facial features similar to Europeans.
Legends say that they came from the direction of the sea (it is unclear whether flying or using boats) and that one day they would return.
There are certain data about the invention of the first balloons, at the hands of the Chinese.
The one who is credited with the invention of the first balloon, is the Chinese military strategist Kongming, who was the inventor of those known today as Chinese lanterns, 2300 years ago.
They were used mostly for reports, and were initially reserved for a military use.
In Europe, the invention of what we commonly call hot air balloon is due to brothers Joseph and Etienne Montgolfier, a paper factory owners with a passion for science.
Thanks to their studies and their experiments, the Montgolfier brothers opened the way to Jean-Francois Pilatre de Rozier (inventor of the eponymous balloon) which together with the Marquis Francois Laurent D'Arlandes, they carried the first balloon flight not bound, flying over Paris and with the wonder and the gaze of thousands of people.
In the early years it was thought that the balloon flew, thanks to a special gas burning generated, which was called Montgolfier Gas.
Alessandro Volta was later realized that, that it was not a special gas but the air density difference between heated and cold air.
Hereafter there were many other air pioneers, both men and women, that brought many improvements to the balloons and flying technique and allowed the development of balloons up to as we know them today.
The gas balloons were used before the evolution and development of the hot-air balloons, and throughout the nineteenth century were the sovereign air.
This is because after the invention of the hot-air balloon, its glory diminished rapidly, in favor of gas balloons (initially hydrogen and then helium) which were more manageable, and more secure because it did not need fire to fly.
The flight principle is simple, a balloon filled with a lighter than air gases, with a volume such that it can lift the loads for which it is designed.
Initially the gas balloons had a net over the ball, which served to contain it and at the same time act as a support for the basket, where passengers were staying, or the loads to be transported.
This kind of balloons, not having to do with hot and cold air -which remember, provide various upward forces - but with a lighter than air gases, whose thrust is uniform in its volume, have a spherical shape and are simpler design (see How to design) than the hot air balloons, or the more complex Rozier balloons.
Today the gas balloons are used, no longer -if not rare occasions- for human flight, but to lead to considerable heights payloads, such as weather sensors, or bound at low altitude for advertising purposes.
-In World War II, the Helium balloons, bound to the earth, they were used to prevent low-flying air strikes.
-Japan, during World War II, produced around 9000 "Balls-bomb". Were balloons capable of carrying explosives or incendiary, and were launched from the east coast of Japan.
They were designed so that were kept at around 10,000 meters, This was possible thanks to a control system, which if the balloon losing altitude unhooked ballast in order to lighten it, while if too up, vent out the excess hydrogen.
At that altitude in three days, thanks to jet Pacific currents, they reached the United States to drop their offensive load.
The Rozier balloon is named after its inventor, Jean-François Pilâtre de Rozier.
After having witnessed at the first flight of balloons of Montgolfier brothers and after flying firs on a balloon, it was also the inventor of this new and innovative ball.
It was basically a hybrid between a gas balloon and a hot air balloon.
The gas cell was contained within another enclosure where it was heated by a flame and its expansion will allow the flight.
Rozier was the one who earned the unfortunate distinction of being the first man to die in a air crash, in fact, during an attempt to cross the english channel the wind changed direction and for reasons not yet clarified, rushed leading to the death its inventor.
In modern times much it has changed in the Rozier balloons and were recently used to establish different primates.
The diagram at right shows the Breitling Orbiter 3 in 1999 that allow to Bertrand Piccard and Brian Jones to make the first travel around the world in a balloon.
The small red capsule -in the bottom of the photo- is the crew housing where there are beds, the cockpit with computers that control the burners, and above it the burners themselves, who have the task of heat the 'air inside of the enclosure and the gas cell.
Inside the outer casing we can notice the gas cell (helium), and above the "tent" which has the purpose of thermally isolating the balloon and thus reduce the use of the burners and consequently the propane needed to heat it.
Hot Air Balloon
The Hot Air Balloon is the easier and more popular aerostat today.
It is mainly used for events, races or advertising events, and has now lost its pure means of transport function.
It consists in a casing that has the form of an inverted drop and has the purpose of containing the hot air generated by the burner (usually propane is burned).
At the top of the casing is a valve, called "parachute valve" which serves to vent -When open using a rope- a little hot air and reduce the buoyancy.
The casing is made up of many gores, and it is thanks to their special shape that balloons have rounded shape.
Hanging under the casing there is the basket - usually made with a steel frame and wicker coated- which has the purpose of containing the driver, the passengers and the gas cylinders necessary to flight.
On the top of the basket there are two or more burners, connected via tubes covered with steel mesh, to propane cylinders. When the pilot open the valves, it allows gas to pass through the coils where it vaporizes and mixes with the air and then pass through the pilot flame.
It ignites immediately and produces a powerful flame through which, with the hot air generated balloon can fly.