Paper number 892

INVESTIGATION OF THE STRUCTURAL DAMPING OF THE FULL-SCALE HELICOPTER MAIN ROTOR BLADE MADE OF COMPOSITE LAMINATED MATERIALS

Bosko Rasuo

Aeronautical Department, Faculty of Mechanical Engineering,
University of Belgrade, 27 Marta 80, 11000 Belgrade, Yugoslavia

Summary

In this paper experimental results of structural vibratory testing for the light multipurpose helicopter main rotor blade of composite laminated materials are presented. The aim of the main rotor blade vibratory testing was to define the basic aeroelastic properties of the blade. This testing included determination of the natural oscillation modes and natural frequency of the structure in oscillations, as well as defining the blade structural damping. The measurement was performed for three different full-scale models with two different types of cores of the main rotor blade: Nomex (phenolic honeycomb) and Rohacell (polyurethane foam), and the results are presented in this paper.

Keywords

structural damping, phenolic honeycomb, polyurethane foam, vibratory characteristics of the helicopter main rotor blade made of composite laminated materials.