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Airplane

Good afternoon, Dennis, Ann.Good afternoon, all my teachers, and all my friends.Welcome to my presentation.My name is Wayne.Today, I would like to talk about airplane.Airplane is one of the most important inventions in human’s history.Human beings had dreamed to fly like birds for thousands of years.Finally one day, the dream came ture.Now a days, we can fly faster than birds, and we can fly higher than birds.Well, here we are.First, what is an airplane? Is every machine that can fly in sky called airplane? The most important characteristics of plane are the fixed wings, density is higher than air, and power-driven forward.So we can’t claify airships, gliders or helicopters as airplanes.As we all know, the first airplane was invented by the Wright brothers.Here’s Wilbur and younger brother Orville.There were a lot of people flew in sky before them.Then why we say these brothers invented the first airplane? There had three key evaluation standards: the plane should have its own power, it can fly naturally and at even speed, and it can land without damage.Then, I’d like to talk about the advantage and disadvantage.The advantages are Quick travel, Comfort ,Safety and Reliability.There is no traffic jam in sky and airplanes rarely crash.And it’s not a problem even there’re rivers, mountains, or oceans in your way.That’s why airplanes are widely used in military field.The disadvantages are delay and high price.Inventors continued to improve airplanes after the Wright Brothers, and this led to the invention of jets, which are used in both the military field and commercial airlines.A jet is an airplane propelled by jet engines.Jets is much faster than propeller-powered aircrafts and at higher altitude-as high as 10,000 to 15,000 meters(about 33,000 to 49,000 ft).Next, about categories.There are many kinds of categories, as by the type of engines, by functions, by shape, such as number of wings or engines, shape of tail, by characteristics, such as speed, covered distance, etc.We usually claify airplanes by functions.There are two main categories:military airplane and civil airplane.We always claify civil airplanes to trunk liners and regional airplanes by number of its seats and the covered distance.But for military airplane, we are used to claify them by their functions.They are fighters, bombers, attack aircrafts, reconnaiance aircrafts, transports and AWACS(Airborne Warning And Control System).At the last, about the performance of airplane.Empty weight and Maximum take-off weight.We can calculate the carrying capacity of paengers or cargos of certain airplane.Maximum level speed & cruise speed，indicate how fast an airplane can fly.absolute ceiling & service ceiling, mean how high an airplane can fly.maximum total range, indicates the distance an airplane can fly.Here are some records about airplanes.The fastest plane, SR-71.The largest plane, An-225.The highest record is belong to MiG-25M.the range record was created by Virgin Atlantic GlobalFlyer on March 3, 2005.In a conclusion,with the development of science and technology，modern airplanes will be Faster , Higher, and safer in the future.Thank you!

Wayne

Jan 19th, 2013