In this paper results and conclusions obtained from the study of the aeroelastic instability of hingeless helicopter blades are presented. First, the large amplitude coupled flap-lag equations of motion of a hingeless elastic helicopter blade are solved using an asymptotic expansion procedure in multiple time scales. Both hover and forward flight cases are considered. Stability boundaries and amplitudes of nonlinear response are obtained. From these, the importance of the nonlinear coupling and the effect of the periodic coefficients is determined. Next, using a system of linearized coupled flap-lag-pitch equations in hover, various divergence mechanisms for hingeless blades are shown. Finally, the flutter boundaries for coupled flap-lag-pitch are obtained. The effect of the torsional degree of freedom on the flap-lag type of instability is investigated. Similarly the effect of lag on the flap-pitch type of instability is considered. In addition, the effect of various blade parameters on the stability boundaries is shown.
Some conclusions regarding the aeroelastic stability of hingeless helicopter blades in hover and in forward flight
1973-10-01
Miscellaneous
No indication
English
Aeroelastic Stability of Hingeless, Elastically Tailored Rotor Blades in Hover
British Library Online Contents | 1993
|Refined Aeroelastic Analysis of Hingeless Rotor Blades in Hover
Online Contents | 1997
|Aeroelastic instabilities of hingeless helicopter blades
AIAA | 1973
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