15.2: Display CP, CG and NP
After a computation with the Vortex-Lattice-Method the centre of pressure, the
centre of gravity and the neutral point are available. In case of computing a
symmetrical lift distribution is the centre of pressure equal with the centre
of gravity.
The neutral point represents the most rear possible location for the centre of
gravity. If the centre of gravity is located behind the neutral point the
flight condition is instable, the airplane cannot be controlled by hand.
Click the following buttons to make the centre of pressure, the centre of
gravity and the neutral point visible.
XP = centre of pressure
XG = centre of gravity
XN = neutral point
The picture below illustrates these functions.
In case of computing an asymmetrical lift distribution, e.g. caused by a
single-sided flap deflection, the centre of pressure moves out of the symmetry
plane. Then the total force does not attack in the centre of gravity, the
effect is e.g. a roll of the airplane. The pictures below illustrates the
effect.