Why Can’t You Switch Seats in an Empty Airplane?

People often say an object’s center of mass is the location at which all of the gravitational force acts.

The gravitational force pulls on all parts of an object, not just one point.

If I want this stick thing to be in rotational equilibrium, I have to push up with a force equal to the total gravitational force.

All parts of the plane interact with the air and can produce an upward-pushing force.

This point is often called the center of lift.

With the gravitational force and lift at the same location, the net torque due to these two forces is zero .

But what if we moved the plane's center of mass forward?.