## How an Airplane Generates Lift

written by: Vin Reyes•edited by: Rebecca Scudder•updated: 12/21/2010

Are you one of the people wondering how does an airplane work and how does it generate lift to be able to fly in the air? The answer might amaze you. Find out more about the way an airplane works.

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### How Does an Airplane Work

A lot of people are amazed by an aircraft’s ability to lift itself from the ground and sustain varying levels of flight. With all the weight and metal components involved in making an aircraft, you might be wondering how can it lift and stay afloat in the air? The answer depends on two important factors, namely:

• The wings of the aircraft: and
• Thrust

It would be safe to assume that an aircraft creates positive lift through the wings attached on both sides of the airframe. The cross section of the wing will reveal a shape known as an airfoil. This shape is what enables all that metal, luggage, cargo and crew to be lifted off the ground in a precise and controlled manner. Keep in mind that the body of the aircraft is shaped in a similar manner as well as other external components such as the rudder and tail fins.

The principle behind the airfoil’s shape is clearly described by Bernoulli’s Principle. Daniel Bernoulli is a noted expert in fluid dynamics and his work is still highly regarded up to this day. It states that as velocity increases, pressure decreases and while velocity decreases the pressure will increase.

As air travels to the leading edge of the wing, there is an acceleration of the relative wind as air flows above and under the surface of the wing. The shape of the airfoil enables the air to flow faster on the upper wing surface because the camber on the upper surface is greater than that on the lower surface of the wing. Simply said, the air flowing on the upper camber will flow faster than the air flowing beneath the lower camber.

This variation and differences in pressure creates lift under the airfoil as the airplane points up to the sky. But lift can only be generated through thrust. This is the reason why an aircraft needs sufficient space to take off as it needs to build up speed to create lift. Remember that all aircraft require a full power application when taking off, as a minimum speed must be obtained before it is eligible for lift off. With that being said, the airfoil shape of the wings are one of the main factors in how an airplane generates lift off into the sky.

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The flaps on the wings of the plane are also shaped like an airfoil and serve two critical factors to any aircraft: flaps are both lift and drag inducing devices. A full flaps application is noticeable on any airplane as it takes off as extending the flaps also extends the area of the airfoil - meaning extra lift can be obtained.

During landing procedures, flaps can also be applied to generate drag (although this depends on the current airspeed) but only to a certain degree. Not enough lift or thrust may result in a stall and this is not an ideal circumstance for any flying activity. A stall can be simply be described as lost of lift due to insufficient thrust or too much angle of attack (the angle of the airfoil in relation to the natural horizon.)

The wings are only a small part of how an airplane works, as other components like the powerful engine or engines and the shape of the aircraft itself are all important factors in achieving a sustained level of flight.

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### Resources and Image Credits

Resources:

www.free-online-private-pilot-ground-school.com

Image Credits:

www.public-domain-photos.com/