Investigation of the active-twist rotor response of various rotor system configurations during shipboard engagement and disengagement operations

Abstract

The unique hazard of excessive blade flapping during the rotor engage and disengage phase of shipboard helicopter operation and previous control strategies investigated for mitigating this problem are briefly presented. A hybrid control strategy is proposed that combines a previously deemed unfeasible passive approach known as the collective pitch scheduling and an active integral twist due to embedded Active Fibre Composites (AFCs). This stipulates the examination of the active twist authority of the active rotor system in this unique phase of helicopter operation and associated environment. The preliminary results of such a study are presented for a generic active blade based on the 1/6 th Mach-scaled Integral Active Twist Rotor (IATR) and an empirical steady airwake model over a generic ship deck. The results demonstrate the dependence of the active twist authority on the blade tip geometry and the aerodynamics envir