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Relation of CG and CP

Asked by: 9321 views Aerodynamics

If I lower the flap CP will be changed, does it change CG or does it effect on CG.? 

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1 Answers



  1. Alex Weeks on Jan 29, 2015

    Center of Gravity (CG) is a function of aircraft weight and loading (where the weight is placed).

    Center of Pressure is a function of wing shape.

    When you lower the flaps you change the shape of the wing thus changing the location of the center of Center of Pressure. It moves aft.

    So, when flaps are extended, CG doesn’t move but CP does move. The relationship between the two changes because CP moved aft and the spread between the two locations increases.

    All other things equal, having the CG and CP farther apart increases longitudinal static stability.

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