Download - NASA
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Real part, per rev (expanded scale)<br />
Figure 4. Eigenvalues for control-system stiffness variations (50-I50% of 13, O00 ft'Ib/rad). C97 model with additional<br />
flutter-solution degrees of freedom; 86% rotor speed at 250 KTAS. (a) Symmetric modes. (b) Antisymmetric modes.<br />
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43