The rotary wing industry has striven to develop a bearingless main rotor (BMR) having no mechanical bearings. All true BMR systems are limited by the strength in static-fatigue loads versus flapwise flexibility, resulting in limited G-maneuvers from a highly responsive rotor system. Our soft-hub rotor concept allows tilting of the rotor by a disc moving the virtual hinge inboard, eliminating this undesirable limitation. It provides the simplicity of a true bearingless main rotor system with flapping angles up to plus-or-minus 15 degrees and allows the BMR to be used on all rotorcraft configurations, even tandem rotors. The objective is to develop a feasible soft-hub design based on the use of existing composite materials. Various levels of "soft hub" stiffness will be analyzed to obtain a match of mission and rotorcraft response requirements. The soft-hub rotor concept has universal applications for rotor systems allowing co-planer BMR rotor configurations with 3, 4, 5, 6, and 7 blades. A Phase II proof-of-concept, scaled wind tunnel test would prove the soft hub capabilities and generate a data base for full scale design.
Potential Commercial Applications: The system would be of value to military and civilian rotorcraft industries.STATUS: Phase I Only
