Page 486 - PPL-engelsk 2025

Principles of flight

5.7.2 Degrees of stability

We are talking about 3 degrees of stability:

- stable - the motion is stopped

- indifferent (neutral) - the motion is not stopped, but does not get worse

either

- unstable - the motion is getting bigger and bigger

In the drawing here

you can see how the

2 types and 3 degrees

of stability are

related.

In practice, a center of gravity located far forward will cause problems with

raising the nose of the aircraft during landing.

If the center of gravity is too far back, the aircraft will tend to over rotate during

takeoff, this can cause the speed to become low and the angle of attack to be
high. This can cause a stall during takeoff.

When the center of gravity is too far back, the aircraft is more difficult to correct

from a spin due to the shorter distance from the center of gravity to the rudder.

Flight Theory PPL(A)(UL)/LAPL Henning Andersen, Midtjysk Flyveskole© 2025 486