An Elementary Explanation of the Flutter Mechanism with Active Feedback Controls

An elementary explanation of wing flutter suppression problems with active feedack control is made using a standard root locus technique. The object of the study is to obtain insight into the control of converging frequency flutter such as the classical bending-torsion flutter of a wing. The model analyzed is a twodimensional, typical section airfoil with pure gain feedback of the main wing motion. In this simple system, stability boundary solutions are expressed in a closed form and valuable information is obtained for various kinds of feedback signals. The results for an exploratory example are discussed. The analysis of this example using Nissim's energy method is also attempted.