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1. History of aviation
In 1486 Leonardo da Vinci began studying birds. Over the next few years he speculated on mechanisms that could help man fly like a bird. He made hundreds of drawings of propellers, helicopters and parachutes. In 1487 da Vinci designed his first flying machine. At first his designs were based on the way bird's flew. Later he realised this was impractical and produceddrawings of machines with fixed wings. He also experimented with what later became known as gliders.
The hot air balloon is the oldest successful human-carrying flight technology. On November 21, 1783, in Paris, France, the first manned flight was made by Jean-François Pilâtre de Rozier and François Laurent d'Arlandes in a hot air balloon created by the Montgolfier brothers.
A hot air balloonconsists of a bag called the envelope that is capable of containing heated air. Suspended beneath is the gondola or wicker basket (in some long-distance or high-altitude balloons, a capsule) which carries the passengers and (usually) a source of heat. The heated air inside the envelope makes it buoyant since it has a lower density than the relatively cold air outside the envelope. 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.
Recently, balloon envelopes have been made in all kinds ofshapes, such as hot dogs, rocket ships, and the shapes of commercial products. 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.
[edit] Early pioneers

Crossing of the English Channel by Blanchard in 1785.

A model of the Giffard Airship at the London Science Museum.

The navigableballoon developed by Dupuy de Lome in 1872.
On 8 August 1709, Bartholomeu Lourenço de Gusmão, a Portuguese Jesuit priest, demonstrated the raising of some instrument, of uncertain mechanism but likely using hot air, in Lisbon. Witnesses named it the Passarola.[7]
In 1784, Jean-Pierre Blanchard fitted a hand-powered propeller to a balloon, the first recorded means of propulsion carried aloft. In1785, he crossed the English Channel with a balloon equipped with flapping wings for propulsion, and a bird-like tail for steerage.[8]
The 19th century saw continued attempts at adding propulsion to balloons. The first person to make an engine-powered flight was Henri Giffard who, in 1852, flew 27 kilometres (17 mi) in a steam-powered airship.[9] Airships would develop considerably over the nexttwo decades: In 1863, Dr. Solomon Andrews devised the first fully steerable airship, the Aereon, although it had no motor.[10] In 1872, the French naval architect Dupuy de Lome launched a large limited navigable balloon, which was driven by a large propeller and the power of eight people.[11] It was developed during the Franco-Prussian war, as an improvement to the balloons used for communicationsbetween Paris and the countryside during the Siege of Paris by Germans.
Early forms of gliding had existed in China perhaps by the 4th century AD according to the writing of the Daoist Ge Hong, and certainly by the time of Emperor Wenxuan of Northern Qi (r. 550–559 AD) who used men sentenced to death as test pilots for his man-flying kites launched from a tower.[1] Some hang gliderflights have been recorded as early as 875 AD, when Abbas Ibn Firnas attempted such a flight in Al-Andalus.[2] Most early glider designs did not ensure safe flight; the problem was that early flight pioneers did not understand the underlying principles that made a bird's wing work. Starting in the 1880s technical and scientific advancements were made that led to the first truly practical...