Main rotor system for helicopters

摘要

A main rotor is provided for use in a rotary winged model aircraft. The main rotor includes a rotor hub assembly rotatable about a vertical axis and at least two main rotor blades. Each of the main rotor blades extends in a radial direction from the rotor hub assembly. The main rotor blades each include a tip end positioned to lie in spaced-apart relation to the rotor hub assembly and a root end coupled to the rotor hub assembly for pivotable folding movement from an initial horizontal position perpendicular to the vertical axis about a horizontal axis through a desired folding angle of about 90 DEG . Forces transmitted to the rotor hub by the rotor blade during a crash-landing of a rotary winged model aircraft including the main rotor are minimized due to movement of the rotor blades through the desired folding angle.