# Center of Pressure(CP) [duplicate]

The center of pressure is:

• A)The point at which the Total Aerodynamic Force acts
• B)The point where the lift force acts
• C)The point where the resistance force acts

Only one answer is correct,i think is B or A but the question is really strange.

• Welcome to aviation.SE. We would like to help you, but we need to understand where you're having a problem. Why you're not sure between A and B? What doubts do you have? Why you think the question is strange? – Federico Feb 22 at 20:22
• Closely related, perhaps a dupe? – Pondlife Feb 22 at 23:04

## 1 Answer

The fact that Total Aerodynamic Force is capitalized indicates it is a term that can be researched:

Total Aerodynamic Force includes drag, therefor the answer is B) the point where the lift force acts.

• Drag will determine the vertical position of the CP while lift is responsible for its lengthwise position. Since we only look at the lengthwise position for further analysis, it is sufficient to only use lift to determine the CP. But strictly speaking you need to look at both forces in order to pin down the CP location. +1 – Peter Kämpf Feb 23 at 3:20
• or, in other words, if you use Total Aerodynamic force (TAF), you would perform a Vector Calculation, considering the entire (vector representation) of the TAF, which, since it is a vector, has two components, a piece normal (perpendicular) to the Flight Path, (called LIFT), and a piece parallel to the flight path (called DRAG). Then you would do the calculation for each of these and combine the answers to get the 2-D position of the CP. So if all you are interested in is the longitudinal (Horizontal) position of the CP, you simply use Lift, which is the vertical (normal) component of TAF. – Charles Bretana Feb 25 at 15:07