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---Under Construction--- CHAPTER 1-INTRODUCTION Introduction Throughout history, it has been man’s dream to soar the skies. Humans looked up at the birds as inspiration that flight is possible. They tried to mimic the structure and mechanics of birds to achieve the vision that one day, man would be airborne. Most early attempts had failed, very often claiming the lives of the inventors and test pilots. However, some had managed to accomplish what others thought would be impossible. Flying all began with the most primitive flying machines-gliders. History of Gliders The gliders we know today were never as genuine until thousands of years after what is reported to be the first glider which originated in China at approximately 500 BC. This glider was supposedly designed by a contemporary of Confusius, Lu Pan. However, this was mostly recognized as a toy rather than a glider. It was not until 500 AD, that in China, the first manned glider soared. Unfortunately, since these time frames were long ago, not all accounts are clear. As with the assault of the Eben Emael fortress in May 10 1940, where German soldiers managed to use gliders to land and take over the Pegasus Bridge, gliders became common as transportation vehicles in World War II. They provided troopers with an advantage over hostile territory because they could glide for an extended period of time, making it difficult for the enemy to estimate where they would land. Furthermore, equipment such as anti-armor weapons and jeeps were successfully transportable by larger gliders. Today, with the use of highly capable materials and aerodynamic structures, gliders have evolved to be more efficient and effective than ever. Sport of Gliding Eventually after World War I, when matters began to settle down, gliding became a popular sport. It was so especially in Germany, where Germans were developing and flying superior gliders. Gliding became a competition, and it was in Oskar Ursinus that the first German gliding competition was held. Internationally, the sport had not been a competition until 10 years later. The most common competitions involve the glider pilots to fly around a pre-defined route and back to the starting point. This could mean around a set of natural landscapes and back to the starting airport, or around navigation aids and back. CHAPTER 2-WHAT MAKES UP A GLIDER Every aircraft is made up of several components which are critical to its function to achieve flight. A controlled aircraft should contain the following elements: • Fuselage • Wings • Control Surfaces Fuselage Generally speaking, the fuselage of an aircraft is what carries its main payload. This payload could be, for example, fuel. Since a glider does not possess an engine or any fuel, its fuselage is built around the pilots that they carry. Its fibreglass construction accounts for its sleek and smooth design. This creates a more aerodynamic structure. However, with aluminium designs, rivets are a requirement, therefore more drag is created. Wings The wings are very important to the success of an aircraft. Essentially, they are what provides lift for the glider and helps it soar. With no wings, no aircraft would be able to fly without falling back down. A glider’s wings are extremely long and narrow compared to a conventional plane. The aspect ratio of a glider is the slenderness of a wing. Applying this to a glider, we know that the aspect ratio of a glider is high because its wings have a long span and a short width. Another important term to consider is induced drag. This is the drag created during the presence of lift by the wings. With a higher aspect ratio, there is less induced drag because induced downwash angle is averaged throughout the entire aspect ratio. With this information, one may ask, “If a high aspect ratio results in low induced drag, why don’t all aircraft have long and thin wings?” The answer to this is simply because with aircrafts that are tasked to carry heavy payloads, there is a limit for how long and skinny the wing may be before it is no longer able to support such weight. Control Surfaces In order to achieve controlled flight, there are obvious necessities. • Ailerons: To control the roll of an aircraft, the aircraft must include movable divisions of the wings. If the pilot wishes to roll to the right, he/she can move the control stick right. The left aileron will rise, and the right one will lower. To roll to the left, the opposite will occur. • Elevator: In order to increase or decrease the pitch (angle of the glider’s nose) in flight, it is necessary to operate the elevators. Much like the ailerons, the elevators are movable sections, except they are on the tail. To point the glider up, the pilot must pull the control stick back. This will cause the elevators to rise as well. The opposite will occur if the stick is pushed forward. • Rudder: The rudder is also a movable division of the aircraft’s edge, located in a vertical position at the tail. The rudder is used to adjust the aircraft’s nose left or right. This is called the yaw. It is unlike the roll because the aircraft’s wings do not change their angle. |
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