Minimized Fuselage Vibrations Using Advanced Composites

An improvement in fuselage dynamic response was achieved by reducing the shear stiffness of skin panels with the use of an advanced-composite material. Woven 181 -style KEVLAR 49 oriented at 0/90 degrees to the panel edges has a very low shear modulus compared to metals, and yet retains the required static and fatigue shear strengths, as determined by tests. Ground-test and flight-test measurements have verified the improved dynamic response. After approximately 8 months of service exposure, no signs of distress were apparent either from load or environment. Ground-test and in-flight vibration reductions have been achieved.