飞机飞行原理

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How do Airplanes fly ?

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air planes fly?

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Over the last few decades,

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airplanes have certainly revolutionized the way we travel.

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But, have you ever thought of how it flies ?

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How does it navigate ?

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We will get answers for these questions

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from this video in a simple, yet scientific way.

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We will also explore how the flight is controlled in a real-time manner.

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First, let’s look at some history.

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Many crazy flying machine designs were tested

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in the nineteenth century because of mankind’s quest to fly.

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Finally one attempt succeeded.

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Yes, you are right.

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It was the flight of the Wright brothers.

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Their aircraft was a success thanks to an interesting phenomenon of physics.

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The airfoil technology.

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The wing of the aircraft was able to produce a lift

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force in an ingenious way.

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The wings had a curved shape.

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This shape pushes the gushing air downwards as shown.

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Newton’s third law of motion comes into picture here.

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If the wing pushes the air downwards,

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the air should also push the wing in the opposite direction

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with an equal magnitude.

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This eventually results in the lift force

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and the aircraft will be able to fly off the ground.

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Even today the airplanes make use of the same airfoil technology to fly,

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but with a highly aerodynamically optimised airfoil shape

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Thrust force makes an airplane move forward

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To produce this thrust,

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a turbofan engine is used in modern civil aviation aircraft.

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Reaction force of high-velocity exit jet gives the turbofan engine thrust force.

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To produce this high velocity jet,

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the incoming air is passed through

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a compressor, combustion chamber and turbines stages.

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The engine also drives the thrust force from the fans reaction

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Thus the turbofan engines produce a great amount of thrust

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and make the airplane move forward.

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As discussed earlier when the airplane moves forward the relatively flowing air

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over the wing will produce a lift force on the wings.

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Just pause for a moment here and have a closer look at the wing.

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You can note that

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the wing of a modern aircraft is a collection of different parts.

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During take off,

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the flaps and slats are extended downwards as shown.

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This increases the wing area and curvature of the airfoil.

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As the curvature increases air will be deflected more.

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Thus a greater lift force can be derived even at low airplane speed.

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As the airplane speed increases, the lift force rises.

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Finally when the lift is more than the gravitational force,

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the plane takes off.

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During the normal flight,

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the flaps and slats are put it to its original position.

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It is interesting to note that,

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different forces acting on the airplane balance exactly each other

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during the normal flight.

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Now, let’s get into the core of the flight navigation.

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You can navigate the airplane

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the way you want with the help of three different wing attachments.

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Aileron

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Elevator

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and Rudder

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Pilots use them alone or together depending on the situation.

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Assume you want to descend the airplane.

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You can just lower the elevator.

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This will deflect the flow as shown and will produce a lift.

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The lift force will create a moment that will make the nose of the plane go down.

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If you want to climb up,

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just do the reverse.

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Now, let’s assume the airplane has to

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change it’s path.

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You must have an obvious answer in your mind.

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Just turn the rudder.

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Of course, turning the rudder

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will produce a lift force and make the airplane turn as shown.

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But, such a sudden change in flight direction may cause passenger discomfort.

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The professional way is the use of Ailerons.

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Just make one Aileron go up and the other down.

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This will cause difference in the lift forces and the airplane will roll.

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Now observe what happens,

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if the airplane still goes up.

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It is clear that,

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the airplane has changed its path.

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Unlike the previous method,

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the airplane orientation has not changed here.

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All these movement of flaps and

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other devices are controlled from the cockpit using a Fly-by-Wire system.

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In FBW systems the controller computer governs

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exact movement of actuators for a smooth operation.

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You can see the different controllers pilots use to navigate the airplane.

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Fuel required for the airplane is

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stored in the large

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tanks of the wing.

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During landing, it is required to increase the drag.

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For this purpose flaps and slats are activated again.

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Because they have drag racing capability too.

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A wing attachment called spoiler

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is also activated to increase the drag further and reduce the lift.

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An interesting mechanism is used for lowering the flaps.

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The mechanism will rotate as well as displace the flaps.

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We hope you enjoyed the flight journey

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by exploring the science behind the airplane operation.

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Thank you !

 

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