Vibration and flutter of advanced composite lifting surfaces

Abstract

This paper d iscusses the potential effects of composite material laminate tailoring on the vibration and flutter of moderate-to-high a spect ratio wings. Three stiffness models, including elastic cross-coupling, are discussed and compared. Chordwise flexibility is shown to be important to the correct determination of stiffness properties. Laminate ply orientation is shown to provide equivalent sweepback or sweepforward of node lines associated with free vibration. Ply o rientation is also shown to enhance flutter characteristics of wings, but may also sensitize the wing to changes in c.g. location and may even trigger body freedom flutter.