An exampleof these characteristicshasbeen given in …gure 4.4. Thelift coe¢cientincreases almost linearly with the angle of attack until a maximum value is reached, whereupon the wing is said to ”stall”. At small angles of attack, the center of the lift forces acts at about e=c t 0:25. At higher angles of attack - before stalling of the wing - the low starts to separate at the suction side of the wing and the center of the lift force shifts backwards, for instance to about e=c t 0:40.
The moment Mrs about the rudder stock is: