Aircraft Design

Aircraft Design

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  Prof. Richard BannerotMECE 2361 Design I Honors Shahmeer Baweja 1180981 1 Design of Modern Aircraft Some thousands of years ago, humans took inspiration from the flawless flight of several birds and began dreaming of capturing the sky. Manned kites, hot-air balloons and airships were some of the earliest developments in aviation. Modern aviation began with the first successful fully controllable, powered flight of a heavier-than-air plane by Orville and Wilbur Wright in December 17, 1903. Design of modern aircrafts such as Boeing and Airbus are based upon the design and concept of the Wright brothers’ successful aircraft. The first commercial flight was made around 1914. Airplanes are transportation devices designed to move people and cargo from one place to another. They come in a variety of shapes and designs depending on the mission of the aircraft. Commercial aircrafts are the biggest planes and frequently used by millions of people all around the world to travel to places for vacations, businesses and conferences. The aero industry is one of the largest industry in the world with millions of dollars generating from thousands of commercial flights a day. This paper will discuss in details the design of a modern commercial aircraft as seen in the 21st Century. The paper will discuss in details those basic parts that helps the aero plane fly more efficiently and safely than older planes of the early 1930s to late 1950s. The basics structural parts of an aircraft are: fuselage (cockpit, compartments), wing (winglet, aileron, flaps, spoiler, slats), empennage [tail section] (elevator, rudder, stabilizer), power plant [propulsion system] (propeller or turbine engine), undercarriage [landing gear] (wheels, axles, shocks, brakes) as shown in Fig. 1, Fig. 2 and Fig. 3 below
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  Prof. Richard BannerotMECE 2361 Design I Honors Shahmeer Baweja 1180981 2 Figure 1: Basic Structural Parts of an Aircraft ("Aeronautics" NASA) Figure 2: Parts of a plane including those subparts of the main structural parts ("Parts of Airplane" NASA)
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  Prof. Richard BannerotMECE 2361 Design I Honors Shahmeer Baweja 1180981 3 Figure 3: parts of an aircraft landing gear mainly consisting of wheels, axles, shocks and brakes (Kong 2013) Fuselage: The fuselage (Fig 1 and Fig 2) is the main body of the aircraft to which all of the other parts are attached to. The fuselage contains the cockpit (Fig. 1 and Fig. 2) and compartments for the passengers and cargo. The cockpit is a flight deck for the pilots located at the front of the fuselage. The fuselage provides little lift compared to other lift producing parts but it is streamlined to decrease the aerodynamic drag. A streamlined fuselage has the same attributes as
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  Prof. Richard BannerotMECE 2361 Design I Honors Shahmeer Baweja 1180981 4 a streamlined car in that it has a sharp or rounded nose with sleek, tapered body so that the air can flow smoothly around it. (“Aeronautics” NASA). Wings For a plane to be able to fly itself, it must be able to lift itself in the air. The wings (Fig. 1 and Fig. 2) help the plane fly and hover instead of falling down due to gravity or getting opposed in its motion by air in the form of an aerodynamic drag. The winglets (Fig. 2) on the wings reduce most of the drag. (“Parts of Airplane” NASA). There are other lift producing parts of the plane but the wings are most important ones out there. There are different designs of the wings depending on the aircraft type. Most commonly, the outer tips of the wings are higher than where the wings are attached to the fuselage. This upward angle is called the dihedral angle, show in Figure 4 below, which helps keep the airplane from rolling unexpectedly during flight. The wings also carry the fuel for the aircraft (“Aeronautics” NASA) Figure 4: Dihedral angle formed by the wings with the horizontal ("Aeronautics" NASA) Near the tip of the wings is the hinged part of the wing called the aileron (Fig. 2); it is used to roll the wings from side to side. Most aircrafts can also be rolled from side to side by using the spoilers (Fig. 2). Spoilers are plates similar in size to ailerons that are used to put off the flow over the wing and to change the amount of force by decreasing the lift during its deployment. On the rear sections of the wings near the body of the fuselage, there are hinged sections that are called flaps (Fig. 2). Flaps are deployed downward on takeoff to increase the lift produced by the wings and during landing to increase the drag produced by the wings. On some aircraft, the front
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  Prof. Richard BannerotMECE 2361 Design I Honors Shahmeer Baweja 1180981 5 part of the wing that also deflect are called slats (Fig. 2) which are used at takeoff and landing in a similar way to flaps. The spoilers are also used during landing to slow the plane down and to offset the flaps when the aircraft is on the ground. (“Parts of Airplane” NASA). Empennage The empennage or the tail section (Fig. 1) at the rear end of the aircraft consists of smaller wings which provide stability and control during the flight i.e. keep the airplane flying straight. The tail consists of two main parts: a vertical piece called the vertical stabilizer (Fig. 2) which is shaped like a fin and to which the rudder (Fig. 2) is attached and a horizontal piece called the horizontal stabilizer (Fig. 2) to which the elevators (Fig. 2) are attached. (“Aeronautics” NASA). The vertical stabilizer keeps the nose of the plane from swinging from side to side, which is called yaw. The hinged part of the vertical stabilizer, the rudder, control the yaw movement. The horizontal stabilizer prevents an up-and-down motion of the nose, which is called pitch. The hinged part of the horizontal stabilizer on both sides, the elevators, control the pitch movement. (“Parts of Airplane” NASA). How do these stabilizers keep the plane point in the direction of the wind? When the tail end of the airplane tries to swing to either side, the wind pushes against the tail surfaces, returning it to its proper place (“Aeronautics” NASA). The tail section of the aircraft can be designed in a variety of shapes for aesthetic purposes. Power plant The power plant (propulsion system) of the aircraft is the most important part in the design of an aero plane. It is what makes the plane move instead of staying still. In huge and high powered planes such as the commercial aircrafts Boeing and the Airbus, huge turbine engines (Fig. 2) attached beneath the wings, generate thrust to overcome the aerodynamic drag and push
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  Prof. Richard BannerotMECE 2361 Design I Honors Shahmeer Baweja 1180981 6 the air plane forward through the air. Smaller, low power airplanes or jets use propellers (Fig. 1) either on the front end of the aircraft or beneath the wings instead of the turbine engines. (“Parts of Airplane” NASA). In those planes, the propeller is attached to a shaft. The propeller usually consists of three or four blades but may have more as shown in Figure 5 below, and the more the blades there can be, the more the air that can be moved. A 2-bladed propeller from a Beagle Pup A 3-bladed propeller from a Me-109G A 4-bladed propeller from a B- 29 An 8-bladed contrarotating propeller from an Antonov AN-22 Figure 5: Four propellers each having different number of blades ("Aeronautics" NASA) The blades generate lift due to its airfoil shape as it cuts through the air. Since the propeller is pointed forward in the direction of the wind, the force generated by the blades is in a forward direction i.e. the propeller generates thrust like the turbine engines. (“Aeronautics” NASA) Undercarriage The undercarriage (landing gear) consists mainly of struts, wheels and brakes as well as shocks and axles (Fig. 3). The landing gear can be fixed in place or can be retractable. Most of them are retractable. In small airplanes, the gear is fixed which increases drag, but keeps the airplane lightweight. Larger and high powered aircraft such as those commercial aircrafts have retractable landing gear that can accommodate the increased weight. During takeoff, the pilot
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  Prof. Richard BannerotMECE 2361 Design I Honors Shahmeer Baweja 1180981 7 retract the gear which helps to reduce the drag as the air plane ascends. On retraction, the gear goes inside the aircraft. (“Aeronautics” NASA). During landing, the pilot unretract the gears to increase the drag. On touching the ground, the pilot applies the brakes situated on the wheels, the brake bar (Fig. 3) to slow the plane. The shocks (Fig. 3) are the shock absorbers that absorb the shock of landing (Kong 2013) while the struts and axles support the gear preventing it from breaking loose due to contact with the ground on landing.
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  Prof. Richard BannerotMECE 2361 Design I Honors Shahmeer Baweja 1180981 8 Works Cited "Aeronautics." Virtual Skies. National Aeronautics and Space Administration, n.d. Web. 25 Apr. 2014. <http://virtualskies.arc.nasa.gov/aeronautics/4.html>. Kong, Major. "How Airliners Work - Landing Gear." Daily Kos. Kos Media, LLC, 17 May 2013. Web. 26 Apr. 2014. <http://www.dailykos.com/story/2013/05/17/1209758/-How- Airliners-Work-Landing-Gear>. "Parts of Airplane." National Aeronautics and Space Administration, n.d. Web. 26 Apr. 2014. <http://www.grc.nasa.gov/WWW/k-12/airplane/airplane.html>.