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## Fundamentals of Flight

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**Fundamentals of Flight**A Basic Introduction to Aerodynamics**The Four Forces of Flight**The four forces act on the airplane in flight and also work against each other.**The Four Forces of Flight**The four forces act on the airplane in flight and also work against each other.**The earth’s gravity pulls down on objects and gives them**weight. Weight counteracts lift.**How do we explain lift?**What’s it take to create lift? Newton’s Laws of Motion and Bernoulli’s Principal are used to explain lift. Air and motion.**Newton’s Second Law: force causes a change in velocity**which in turn generates another force. Newton’s Third Law: net flow of air is turned down resulting in an ‘equal and opposite’ upward force.**Newton’s Third Law states that for every action there is**an equal and opposite reaction.**Bernouli’s first practical use of his theorem**Where are venturi tubes used today? Venturi Tube**Hold two sheets of paper together, as shown here, and blow**between them. No matter how hard you blow, you cannot push them more than a little bit apart!**Bernoulli’s Theory in Action**Air speeds up in the constricted space between the car & truck creating a low-pressure area. Higher pressure on the other outside pushes them together.**A wing is really just half a venturi tube.**What is a wing?**A fluid (and air acts like a fluid) speeds up as it moves**through a constricted space Bernoulli’s Principle states that, as air speeds up, its pressure goes down.**Bernoulli's Principle: slower moving air below the wing**creates greater pressure and pushes up.**Bernoulli’s Principle: Air moving over the wing moves**faster than the air below. Faster-moving air above exerts less pressure on the wing than the slower-moving air below. The result is an upward push on the wing--lift!**Bernoulli’s Principal: pressure variation around the wing**results in a net aerodynamic pushing up.**A wing creates lift due to a combination of Bernoulli’s**Principal & Newton’s Third Law**Interactive Wright 1901 Wind Tunnel**Interactive Wright 1901 Wind Tunnel**Internal ribs define the wings shape**Wing Shape**This US Navy Carrier Jet has a very small wing, how can it**fly? Can you see the airfoil? Why is the wing small? What other aerodynamic devices can you see?**Elevator Controls Pitch**The ELEVATOR controls PITCH. On the horizontal tail surface, the elevator tilts up or down, decreasing or increasing lift on the tail. This tilts the nose of the airplane up and down.**Ailerons Control Roll**The AILERONS control ROLL. On the outer rear edge of each wing, the two ailerons move in opposite directions, up and down, decreasing lift on one wing while increasing it on the other. This causes the airplane to roll to the left or right.**Rudder Controls Yaw**The RUDDER controls YAW. On the vertical tail fin, the rudder swivels from side to side, pushing the tail in a left or right direction. A pilot usually uses the rudder along with the ailerons to turn the airplane.**Vectors to final approach – instructions to a pilot to**steer a specific course “Turn left heading 270, vectors to final approach course Grand Junction.” A physics term to define magnitude and direction. Vectors: Two Kinds in Aviation**Vectors**• A physics term to define magnitude and direction. 20 Direction: 045 Magnitude: 20 45 o What?**20 What Units?**Some unit of distance, force, acceleration, time, etc. Vectors**What good are they? Or, “I was told there would be No**Math!” They help us find out what happens! Vectors Adding Vectors together = Resultant**Vectors**Lift • Therefore, any “vector” can be “analyzed” or broken down into horizontal and vertical components**Vectors: “The MATH”**Pythagorean Properties of right triangles**Which of these airplanes will speed up?**Which will slow down?**Drag is the force of resistance an aircraft ‘feels’ as**it moves through the air.**For an airplane to take off, lift must be greater than**weight. For an airplane to speed up while flying, thrust must be greater than drag.**Engines (either jet or propeller) typically provide the**thrust for aircraft. When you fly a paper airplane, you generate the thrust.**What will happen when the fire-fighting plane drops its load**of water?