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The hot air balloon is the oldest successful human-carrying flight technology. It is in a class of aircraft known as balloon aircraft. On November 21, 1783, in Annonay, France, the first untethered manned flight was made by Jean-François Pilâtre de Rozier and François Laurent d'Arlandes in a hot air balloon created on December 14, 1782 by the Montgolfier brothers. Hot air balloons that can be propelled through the air rather than just being pushed along by the wind are known as airships or, more specifically, thermal airships.
A hot air balloon consists of a bag called the envelope that is capable of containing heated air. Suspended beneath is a gondola or wicker basket (in some long-distance or high-altitude balloons, a capsule), which carries passengers and (usually) a source of heat, in most cases an open flame. The heated air inside the envelope makes it buoyant since it has a lower density than the relatively cold air outside the envelope. As with all aircraft, hot air balloons cannot fly beyond the atmosphere. Unlike gas balloons, the envelope does not have to be sealed at the bottom since the air near the bottom of the envelope is at the same pressure as the surrounding air. In today's sport balloons the envelope is generally made from nylon fabric and the mouth of the balloon (closest to the burner flame) is made from fire resistant material such as Nomex. Beginning in the mid-1970s, balloon envelopes have been made in all kinds of shapes, such as hot dogs, rocket ships, and the shapes of commercial products, though the traditional shape remains popular for most non-commercial, and many commercial, applications.
Unmanned hot air balloons are popular in Chinese history. Zhuge Liang of the Shu Han kingdom, in the Three Kingdoms era (220–280 AD) used airborne lanterns for military signaling. These lanterns are known as Kongming lanternsThere is also some speculation, from a demonstration led by British modern hot air balloonist Julian Nott in the late 1970s and again in 2003, that hot air balloons could have been used by people of the Nazca culture of Peru some 1500 to 2000 years ago, as a tool for designing the famous Nazca ground figures and lines. The first documented balloon flight in Europe was demonstrated by Bartolomeu de Gusmão. On August 8, 1709, in Lisbon, he managed to lift a balloon full of hot air about 4.5 meters in front of King John V and the Portuguese court.
The first clearly recorded instance of a balloon carrying passengers used hot air to generate buoyancy and was built by the brothers Joseph-Michel and Jacques-Etienne Montgolfier in Annonay, Ardeche, France. After experimenting with unmanned balloons and flights with animals, the first tethered balloon flight with humans on board took place on October 15, 1783. Etienne Montgolfier made at least one tethered flight from the yard of the Reveillon workshop in the Faubourg Saint-Antoine. It was most likely on October 15, 1783. A little while later on that same day, Pilatre de Rozier became the second to ascend into the air, to an altitude of 80 feet, which was the length of the tether. The first free flight with human passengers took place 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, successfully petitioned for the honor. The first military use of a hot air balloon happened during the battle of Fleurus (1794) where the French used the balloon l'Entreprenant as an observation post. The first manned flight of a balloon in the United States took place on June 24,1784.
Modern hot air balloons, with an onboard heat source, were pioneered by Ed Yost, beginning in the 1950s; his work resulted in his first successful flight, on October 22, 1960. The first modern-day hot air balloon to be built in the United Kingdom (UK) was the Bristol Belle in 1967. Today, hot air balloons are used primarily for recreation.
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 21,027 m (68,986 ft). He took off from downtown Mumbai, India, and landed 240 km (150 mi) south in Panchale. The previous record of 19,811 m (64,997 ft) had been set by Per Lindstrand on June 6, 1988 in Plano, Texas. As with all unpressurized aircraft, oxygen is needed for all crew and passengers on any flight that exceeds an altitude of about 15,000 ft (4,600 m).
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 7,671.91 km (4,767.10 mi) from Japan to Northern Canada. With a volume of 74 thousand 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 recorded the highest ground speed for a manned balloon at 245 mph (394 km/h). The longest duration record was set by Swiss psychiatrist Bertrand Piccard, 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 300 miles (480 km) south of Cairo. The two men broke distance, endurance, and time records, traveling 19 days, 21 hours, and 55 minutes. Steve Fosset broke the record for shortest time around the world on 3 July 2002. The new record is 320 h 33 min.

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