The Innovative Blade Attachment for the new H145 Bearingless Main Rotor

With the market introduction of the EC135 the bearingless main rotor (BMR) as a novel main rotor system was put into series production. Since then a chain of interconnected research programs led to the next generation of BMR. It now enhances the qualities of the H145 regarding the aspects of useful load, comfort of ride, purchase and maintenance cost as well as operational features. The design targets definition and their implementation by innovative solutions are summarized hereafter. The focus is put on the modular design of the main rotor system which is realized by an integrated flexbeam and control cuff assembly and a separate rotor blade joined together by a bolted connection using flat laminate lay-up instead of fiber loops. A detailed view is given on the development of the novel blade attachment from design considerations and manufacturing aspects over parametric subcomponent tests to full scale testing.