Ap Eng. Hot Air Balloons

Willis 1 Caitlin Willis Ms. McGee AP English 12 11 April 2009 The Hot Air Balloon The hot air balloon, with its ingenious application of scientific facts, is the oldest successful human carrying flight technology. Hot air balloons are based on the basic principle that warm air rises in cooler air, because hot air is lighter since it has less mass per unit of volume. The actual balloon part, usually made of nylon, is capable of containing the hot air. It must be so large because it takes a large amount of air to be lifted off the ground. For example, to lift 1,000 pounds, it takes about 65,000 cubic feet of hot air (“Hot Air Balloon Designs”). Launching the balloon takes about ten minutes and involves inflating the balloon with powerful fan. In order for the hot air balloon to remain buoyant, a burner is used to propel hot air upwards. The burner uses propane as fuel and it is stored in compressed liquid form in cylinders placed under the balloon basket. The fuel is highly compressed, allowing it to run quickly through the intake hose, which runs down to the bottom of the cylinder. “Once the balloon is full of air, it will still lie on the ground until the burner is fired, heating the air in the envelope and causing it to rise.” When the pilot ignites the fuel, it heats up the metal around the burner, making the flame stronger. The pilot must do this regularly to ensure that the flight is stable. The passenger compartment is a basket made of wicker, which is light and flexible, and attaches under the envelope. The air won’t escape from the bottom of the open envelope because hot air rises, and buoyancy

Willis 2 keeps it moving. As long as the air remains hot, the hot air balloon will continue to rise. However, the balloon won’t rise forever as there is an upward altitude limit and the air becomes too thin that the buoyant force is too weak to lift the balloon (“Hot Air Balloon Designs;” “How do Hot Air Balloons Work”). The pilot can make the balloon rise by releasing the propane valve which allows the propane to flow into the burner, firing the flame into the envelope. To make the balloon go down, the pilot can pull the parachute valve, located at the top of the balloon. The parachute valve is a circle of material cut out of the balloon, which is attached to a cord running down to the basket. When the cord is pulled, hot air is released, decreasing the air temperature, causing the balloon to gradually sink (“How a Hot Air Balloon Works”). There are no horizontal controls on a hot air balloon, but a pilot who is knowledgeable of the wind currents in the area will go in the right direction. Pilots can still control the horizontal movement by raising and lowering the altitude of the craft, because winds at different altitudes move in different directions (“How do Hot Air Balloons Work”). All the pilot must do is raise and lower the balloon and ride with the wind. Landing the balloon requires bumping the basket along the ground to lessen the impact, and an experienced pilot to do so. Joseph and Etienne Montgolfier, of Annoy France, are the two brothers responsible for the birth of the first hot air balloon in 1782. When they discovered that hot air was lighter than cool air, it lead to the creation of a small silk balloon, which was elevated thirty-two meters in the air. Shortly after, the two brothers gave a public demonstration in which a balloon was elevated ten thousand meters in the air, and the news of this breakthrough was sent to the Science Academy of France. Since the brothers

Willis 3 promised their father to never fly their own machine, a duck, a sheep, and a chicken were the first passengers. The balloon remained in the air for fifteen minutes before crashing to the ground, but the animals were left unharmed. After witnessing the event, Louis XVI allowed Pilatre Rosier and Marquis d’Arlandes, of Lourdes, France to attempt a manned flight with the Montgolfier’s invention. The balloon launched from the center of Paris and lasted for about twenty minutes becoming the first successful manned hot air balloon flight (“The History of The Hot Air Balloon;” “How a Hot Air Balloon Works”). The Montgolfier’s discovery brought them fame and a competition began between the brothers and Rosier as to who could fly the highest, with crossing the English Channel being the ultimate goal. On January 7th 1793, Jean Pierre Blanchard and his American co pilot John Jefferies completed the challenge from the English side, leaving the France to England route still a challenge. Two years later, Rosier attempted this flight but unfortunately died because of a hydrogen bag that he tied near the flames. The next successful major point in hot air ballooning was the first flight in North America by Blanchard. In 1932, Swiss scientist Auguste Piccard was the first to accomplish a manned flight into the Stratosphere, reaching a height of 52,498 feet. Following these successes, many other attempts were made to cross challenging bodies of water. In 1987 Richard Branson and Per Lindstrand became the first people to cross the Atlantic Ocean in a hot air balloon, and conquered the Pacific Ocean in 1991. At last, in 1999, Bertrand Piccard and Brian Jones completed the first flight around the world, which lasted 19 days, 21 hours, and 55 minutes (“The History of The Hot Air Balloon;” “How a Hot Air Balloon Works”).

Willis 4 Nowadays, hot air balloons are used for many different reasons. Hot air balloons are most popularly used for commercial and leisure flights, proving to be popular for people of all ages. Some companies use hot air balloons as a means of advertising, by either having their own shaped balloon, or advertising on the side of the classic balloon envelope. Hot air ballooning has become a popular sport as well, involving races at local festivals all the way to national competitions. For some, the hot air balloon has become a marriage venue, and although it may be a strange concept to some, others find it quite romantic (“How a Hot Air Balloon Works”).

Willis 5 Works Cited “Hot Air Balloon.” Wikipedia, the free encyclopedia. 11 Jan. 2009 . “Hot Air Balloon Designs.” Hot Air Balloons USA, Hot Air Balloon, Hot Air Balloon Rides & More. 11 Jan. 2009 . “How a Hot Air Balloon Works.” Hot Air Ballooning Pictures, History and Information from eBalloon.org. 11 Jan. 2009 . “How do Hot Air Balloons Work.” Christmas Gift Ideas and Experiences | Theatre Breaks | Activity Days | Birthday Gifts. 11 Jan. 2009 . “The History of The Hot Air Balloon.” Essortment Articles: Free Online Articles on Health, Science, Education & More. 11 Jan. 2009 .