Name: 飛機是如何飛行的？ (How do Airplanes fly ?)
Uploaded: 2021-01-14T06:49:56.000Z
Duration: 6 min 23 s
Description: 【看影片學英語】數萬部 YouTube 影片，搭配英漢字典即點即查，輕鬆掌握單字發音與用法，長久累積看電影不必再看字幕。

airplanes have certainly revolutionized the way we travel.

But, have you ever thought of how it flies ?

from this video in a simple, yet scientific way.

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

Many crazy flying machine designs were tested

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

It was the flight of the Wright brothers.

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

The wing of the aircraft was able to produce a lift

This shape pushes the gushing air downwards as shown.

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

the air should also push the wing in the opposite direction

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

a turbofan engine is used in modern civil aviation aircraft.

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

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

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.

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

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 flaps and slats are put it to its original position.

different forces acting on the airplane balance exactly each other

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

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

Pilots use them alone or together depending on the situation.

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.

You must have an obvious answer in your mind.

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.

the airplane orientation has not changed here.

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.

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.

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.