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  • air planes fly?

  • Over the last few decades,

  • airplanes have certainly revolutionized the way we travel.

  • But, have you ever thought of how it flies ?

  • How does it navigate ?

  • We will get answers for these questions

  • from this video in a simple, yet scientific way.

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

  • First, let's look at some history.

  • Many crazy flying machine designs were tested

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

  • Finally one attempt succeeded.

  • Yes, you are right.

  • It was the flight of the Wright brothers.

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

  • The airfoil technology.

  • The wing of the aircraft was able to produce a lift

  • force in an ingenious way.

  • The wings had a curved shape.

  • This shape pushes the gushing air downwards as shown.

  • Newton's third law of motion comes into picture here.

  • If the wing pushes the air downwards,

  • the air should also push the wing in the opposite direction

  • with an equal magnitude.

  • This eventually results in the lift force

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

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

  • but with a highly aerodynamically optimised airfoil shape

  • Thrust force makes an airplane move forward

  • To produce this thrust,

  • a turbofan engine is used in modern civil aviation aircraft.

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

  • To produce this high velocity jet,

  • the incoming air is passed through

  • a compressor, combustion chamber and turbines stages.

  • The engine also drives the thrust force from the fans reaction

  • Thus the turbofan engines produce a great amount of thrust

  • and make the airplane move forward.

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

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

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

  • You can note that

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

  • During take off,

  • the flaps and slats are extended downwards as shown.

  • This increases the wing area and curvature of the airfoil.

  • As the curvature increases air will be deflected more.

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

  • As the airplane speed increases, the lift force rises.

  • Finally when the lift is more than the gravitational force,

  • the plane takes off.

  • During the normal flight,

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

  • It is interesting to note that,

  • different forces acting on the airplane balance exactly each other

  • during the normal flight.

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

  • You can navigate the airplane

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

  • Aileron

  • Elevator

  • and Rudder

  • Pilots use them alone or together depending on the situation.

  • Assume you want to descend the airplane.

  • You can just lower the elevator.

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

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

  • If you want to climb up,

  • just do the reverse.

  • Now, let's assume the airplane has to

  • change it's path.

  • You must have an obvious answer in your mind.

  • Just turn the rudder.

  • Of course, turning the rudder

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

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

  • The professional way is the use of Ailerons.

  • Just make one Aileron go up and the other down.

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

  • Now observe what happens,

  • if the airplane still goes up.

  • It is clear that,

  • the airplane has changed its path.

  • Unlike the previous method,

  • the airplane orientation has not changed here.

  • All these movement of flaps and

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

  • In FBW systems the controller computer governs

  • exact movement of actuators for a smooth operation.

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

  • Fuel required for the airplane is

  • stored in the large

  • tanks of the wing.

  • During landing, it is required to increase the drag.

  • For this purpose flaps and slats are activated again.

  • Because they have drag racing capability too.

  • A wing attachment called spoiler

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

  • An interesting mechanism is used for lowering the flaps.

  • The mechanism will rotate as well as displace the flaps.

  • We hope you enjoyed the flight journey

  • by exploring the science behind the airplane operation.

  • Thank you !

air planes fly?

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B2 UK airplane wing lift flight thrust aircraft

How do Airplanes fly ?

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    Yuan Yen posted on 2017/04/14
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