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The LIFT formula

Updated: Feb 13, 2021

You have to know the lift formula as a PPL by heart, so take the time to learn it. Here it is:

Lift is equal to the coefficient of lift times half rho times velocity squared times surface area (of the wing).

= Lift

= Co-efficient of Lift

= half rho (rho relates to air density)

= velocity squared (velocity is a vector quantity made up of speed and direction)

= surface area of the wing

Just in case you can't quite remember what each part of the formula represents, the next picture should give you a little reminder:

- the Co-efficient of Lift This is a number between 0 and 2 worked out by the clever folk who are involved in aircraft design and engineering. Us pilots don't have to worry too much about this number, just that it is a part of the all important Lift Formula, and that it is affected by the Angle of Attack of the wing, and the Shape of the wing.

Can you, as the pilot have an effect on the Angle of Attack of the wing? Can you change it in any way?

Can you as the pilot of a light training aircraft change the shape of the wing in any way? Turn it into a Delta Wing? Can you increase it's Camber?

- Rho

Rho relates to the density of the air at the level and in the conditions in which you are currently flying.

Can you, as the pilot change the density of the air that you are busy flying in?


- Velocity squared

Velocity relates to the speed at which you are flying. Notice its effect is squared, so it has a very significant impact on the creation of lift.

Can you as the pilot change the speed of the aircraft in any way?

- the Surface Area of a Wing

This is the square foot / meter of the wing.

Can you, as the pilot, change the surface area of your light training aircraft?