Admin
Admin
Posts : 1012
Reputation : 6
Join date : 2010-02-10
Age : 48
 |  Subject: History of Airships and Balloons  14/11/2010, 12:31 pm | |
| 
There are two kinds of floating lighter-than-air or LTA craft: theballoon and the airship. A balloon is an unpowered LTA craft that canlift. An airship is a powered LTA craft that can lift and then maneuverin any direction against the wind.BuoyancyBalloons and airships lift because they are buoyant, meaning that thetotal weight of the airship or balloon is less than the weight of theair it displaces. The Greek philosopher Archimedes first established the basic principle of buoyancy.Hot air balloons were first flown by the brothers Joseph and EtienneMontgolfier as early as the spring of 1783. While the materials andtechnology are very different, the principles used by the earliesteighteenth-century experimenters continue to carry modern sport andweather balloons aloft.Types of AirshipsThere are three types of airships: the nonrigid airship, often called ablimp; the semirigid airship, and the rigid airship, sometimes called aZeppelin.
The Montgolfier brothers, born in Annonay, France, were the inventorsof the first practical balloon. The first demonstrated flight of a hotair balloon took place on June 4, 1783, in Annonay, France.Montgolfiere BalloonJoseph and Jacques Montgolfier, paper mill owners, were trying to floatbags made of paper and fabric. When the brothers held a flame near theopening at the bottom, the bag (called a balon) expanded with hot airand floated upward. The Montgolfier brothers built a larger paper-linedsilk balloon and demonstrated it on June 4, 1783, in the marketplace atAnnonay. Their balloon (called a Montgolfiere) lifted 6,562 feet intothe air.First PassengersOn September 19, 1783, in Versailles, a Montgolfiere hot air ballooncarrying a sheep, a rooster, and a duck flew for eight minutes in frontof Louis XVI, Marie Antoinette, and the French court.First Manned FlightOn October 15, 1783, Pilatre de Rozier and Marquis d'Arlandes were thefirst human passengers on a Montgolfiere balloon. The balloon was infree flight, meaning it was not tethered.On January 19, 1784, a huge Montgolfiere hot air balloon carried sevenpassengers to a height of 3,000 feet over the city of Lyons.Montgolfier GasAt the time, the Montgolfiers believed they had discovered a new gas(they called Montgolfier gas) that was lighter than air and caused theinflated balloons to rise. In fact, the gas was merely air, whichbecame more buoyant as it was heated.
Less than two weeks after the ground-breaking Montgolfier flight, theFrench physicist Jacques Charles (1746-1823) and Nicolas Robert(1758-1820) made the first untethered ascension with a gas hydrogenballoon on December 1, 1783. Jacques Charles combined his expertise inmaking hydrogen with Nicolas Robert's new method of coating silk withrubber.Charlière Hydrogen BalloonThe Charlière hydrogen balloon exceeded the earlier Montgolfier hot airballoon in time in the air and distance traveled. With its wickergondola, netting, and valve-and-ballast system, it became thedefinitive form of the hydrogen balloon for the next 200 years. Theaudience in the Tuileries Gardens was reported as 400,000, half thepopulation of Paris.The limitation of using hot air was balloons was that when the air inthe balloon cooled, the balloon was forced to descend. If a fire waskept burning to warm the air constantly, sparks were likely to reachthe bag and set it afire. Hydrogen overcame this obstacle.First Ballooning FatalitiesOn June 15, 1785, PierreRomain and Pilatre de Rozier were the first persons to die in aballoon. Pilatre de Rozier was both the first to fly and to die in aballoon. Using a dangerous combination of hot-air and hydrogen provedfatal to the pair, whose dramatic crash before a large crowd onlytemporarily dampened the balloon mania sweeping France in the lateeighteenth century.
| |
|
