Equilibrium About an Axis
The aerodynamic moment coefficient Cm, o is defined as
If the profile is attached to a vertical axis located at x — 0 (nose of profile), the equation of equilibrium that will give the equilibrium angle of attack aeq is given by the equation of the moment coefficient
Cm, o (aeq) = 0 —— 2 aeq + 4^
Fig. 15.1 Equilibrium position for the profile
aeq is found to be
aeq = —4 = —0.08
See Fig. 15.1.
The equilibrium is stable because ‘ЩОг < 0.